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Since 1999, The Beljanski Foundation has vigorously worked on finding a natural cure for cancer.
Benign prostatic hyperplasia (BPH) is a non-malignant enlargement of the prostate gland, common in older males, that causes urinary and quality of life problems. In a previous study we found that the Pao pereira extract can attenuate BPH development in a rat model by reducing expression of androgen receptor and 5α-reductase. In this study we looked further into the molecular mechanism of Pao pereira’s anti-inflammatory effect in BPH. We found the Pao extract suppressed the growth of two BPH cell lines: BPH-1 and WPMY-1 by inducing apoptosis via inhibition of the NFκB signaling pathway. These findings suggest that Pao Pereira extract may be a very promising therapeutic for BPH.
We investigated Rauwolfia vomitoria extract as a therapeutic option for benign prostatic hyperplasia, a common disease in older men with serious impact on quality of life. The oral administration of the Rauwolfia extract significantly reduced prostate weight in animals with BPH, which is shown by the decreased thickness of the prostate epithelial layer. Similar effects were observed in the BPH animals treated with finasteride. The Rauwolfia extract significantly reduced the level of androgen receptor and 5 alpha reductase as well as testosterone-induced proliferation markers — Proliferating cell nuclear antigen (PCNA) and Cyclin D1. As evidence of its lack of side effects, Rauwolfia did not reduce sperm counts whereas Finasteride did.
Research conducted at the University of Kansas Medical Center concluded that Rauwolfia vomitoria was effective against ovarian cancer cells both alone and in combination with carboplatin. The combination decreased tumor size in animal experiments by 87 to 90%. The authors conclude that, “Rauwolfia vomitoria has potent antitumor activity and in combination significantly enhances the effect of carboplatin against ovarian cancer.”
Research conducted at the University of Kansas Medical Center on the effect of the plant extracts on ovarian cancer concludes that “In vivo, Pao pereira (Pau pereira) alone suppressed tumor growth by 79% and decreased volume of ascites by 55%. When Pao pereira (Pau pereira) was combined with carboplatin, tumor inhibition reached 97% and ascites was completely eradicated.” Pao pereira (Pau pereira) possesses potent antitumor activity and works in synergy with chemotherapy.
Cancer stem cells are a type of stem cell specific to cancer, that is able to reproduce through self-renewal and regeneration into new tumor cells. Cancer stem cells are thought to survive chemotherapy treatments and provide the basis for tumor regrowth. It is critical to find treatments for cancer stem cells to prevent this disease from resurfacing in a person again and again. Research conducted at Kansas University Medical Center concluded that both the Pao pereira (Pau pereira) and Rauwolfia vomitoria extracts inhibited the proliferation of multiple human ovarian cancer cell lines in vitro.
Human skin fibrosis caused by radiotherapy contains very active ribonucleases (RNases). This is probably connected with the appearance of post-radiotherapy fibrosis. We found that a highly purified extract of Ginkgo biloba golden leaves behaves as a biological regulator of these overactive enzymes. It normalizes to a large extent the excessive RNase activity in an extract of irradiated human skin cells, but does not affect activity of normal human plasma RNase. This extract may be used for treatment of skin fibrosis.
The poor treatment outcomes of pancreatic cancer are linked to an enrichment of cancer stem cells (CSCs) in these tumors, which are resistant to chemotherapy and promote metastasis and tumor recurrence. In these experiments, the pancreatic CSC population, identified using cell surface markers or a tumor spheroid formation assay, was significantly reduced by the Rauwolfia vomitoria extract. In vivo the Rauwolfia extract significantly reduced the tumorigenicity of pancreatic cancer cells. Taken together, these data showed that Rauwolfia preferentially inhibited pancreatic cancer stem cells.
Pancreatic cancers are enriched with cancer stem-like cells (CSCs), which are resistant to chemotherapies, and responsible for tumor metastasis and recurrence. We investigated the extract of a medicinal plant Pao pereira for its activity against pancreatic CSCs. Pao inhibited overall proliferation of human pancreatic cancer cell lines and had limited cytotoxicity to normal epithelial cells. In several assays pancreatic CSC population was significantly reduced. In vivo, the Pao extract significantly reduced tumorigenicity of PANC-1 cells. Further investigation is warranted in using Pao as a novel treatment targeting pancreatic CSCs.
Different tea products could affect the growth of cancer cells. Four popular tea products were evaluated, including 3 green teas and a black tea, namely Bigelow Green Tea with Mint, Kusmi Chinese Green Tea, OnkoTea Green Tea Blend, and Lipton Black Tea. Panels of breast cancer cells, melanoma cells, liver cancer cells, and bladder cancer cells were tested. The results showed that the effects of tea on cell proliferation was concentration dependent. At a higher concentration range, all 4 tea products inhibited the cancer cells, with Onko tea showing the best inhibitory effect.
Benign prostatic hyperplasia (BPH) is one of the most common forms of chronic inflammation in the urinary system of older men. We investigated the therapeutic potential of Pao Pereira extract against BPH development in a testosterone-induced BPH rat model. The administration of testosterone induced the prostate enlargement and either Pao extract or finasteride was evaluated for potential to resolve the BPH condition. Results showed that prostate weights were dramatically reduced in both the Pao and finasteride groups. Notably, Pao treatment did not significantly reduce sperm numbers which is a well-known side effect of finasteride. Pao extract was found to suppress testosterone-induced BPH development by inhibiting androgen receptor expression and activity and by reducing expression of 5α-reductase and Prostate Specific Antigen (PSA). Pao Pereira extract may be a promising and relatively safe agent for BPH.
A DNA based assay for screening compounds for anti-cancer potential identified four green teas with impressive anti-cancer effect. An extract was prepared from a combination of all four of the teas and this extract was tested for anti-cancer activity in cell based assays in Dr. Qi Chen’s laboratory at the Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center. When tested against extracts of other well-known teas, the four green tea blend had the most potent anti-cancer effect. This research was accepted for presentation at the 16th International Conference of the Society for Integrative Oncology and published in EC Nutrition.
Low platelet counts, a condition called thrombocytopenia, is a side effect of chemo drugs that damage the bone marrow stem cells that normally produce platelets. This Phase I trial showed that Beljanski’s RNA fragments could prevent thrombocytopenia by inducing the production of new platelets. Patients taking the RNA fragments had their platelet levels return to normal and chemotherapy treatments were completed without dose reductions, platelet transfusions, or suspensions. The RNA fragments protected platelet levels in patients with many different types of cancer who were taking many different anti-cancer drugs. Moreover, patients did not suffer any negative side effects as a result of taking the RNA fragments.
Pao pereira extract induced dose-dependent apoptosis in all tested pancreatic cancer cell lines. The combination of Pao extract and Gemcitabine had a synergistic effect in the inhibition of cancer cell growth. Mice with pancreatic tumors were treated with Pao extract and Gemcitabine, either alone or in combination. While Gemcitabine did not provide significant inhibition, Pao treatment significantly suppressed tumor growth by 70-72%, and by 78% when combined with Gemcitabine.
In preclinical pancreatic cancer models, Rauwolfia vomitoria extract induced apoptosis in pancreatic cancer cells in a dose-dependent manner. The combination of Rauwolfia extract and gemcitabine had a synergistic effect in inhibiting cell growth. Pancreatic tumor growth was significantly suppressed by Rauwolfia treatment and metastasis was inhibited as well. Adding Rauwolfia extract to gemcitabine treatment further reduced tumor burden and metastatic potential in the gemcitabine resistant tumors. These data suggest that Rau possesses anti–pancreatic cancer activity and could improve the effect of gemcitabine.
ABSTRACT IN ENGLISH: The plant-derived anticancer agent PB-100 (Beljanski® Pao extract) selectively destroys cancer cells, even when multidrug resistant; yet, it does not inhibit normal (non-malignant) cell multiplication. Testing of PB-100 on sixteen cell lines, several multidrug resistant, as well as on five normal cell lines, confirmed our previous results. Flavopereirine and dihydroflavopereirine, the active principles of PB-100, were chemically synthesized and displayed the same selectivity for tumor cells as the purified plant extract, being active at even lower concentrations. List of cell lines tested: brain (4), ovary (2), breast (2), prostate thyroid (2), colon (2), pancreatic, hepatic, kidney, skin, liver
ABSTRACT: In the presence of Mg2+ ions, polynucleotide phosphorylase (PNPase, EC 2.7.7.8) is known to synthesize RNA-like polymers using ribonucleoside-5′-diphosphate (NDP) substrates but to be unable to utilize deoxyribonucleoside substrates. Our experiments show that when MgCl2 is replaced by FeCl3, PNPase becomes able to synthesize deoxyheteropolymers using deoxyribonucleoside-5′-diphosphates (dNDPs). The deoxyheteropolymer formed from the four dNDPs is degraded by pancreatic DNase, but not by RNase, and is readily used as a template by DNA-dependent DNA polymerase. Synthesis of this DNA-like polymer is accomplished de novo without the help of any primer or preexisting template. What is more, dA/dG and dC/dT ratios of polymers synthesized by different bacterial PNPases closely match ratios found in DNA of the bacterial species the enzyme came from.
ABSTRACT: We investigated in vitro the effect of six different substances present in the brain on two human cell lines: U251-BCNU-resistant glioblastoma cells, derived from a highly malignant cerebral tumor, and, as their normal counterparts, CRL 1656 astrocytes. The cytokines IL-4 and IL-10 (alone or together with IL-6), the catecholamine neuromediators dopamine and epinephrine, the steroid hormones progesterone and testosterone all significantly stimulated multiplication of the glioblastoma cells, but enhanced to a much lesses extent multiplication of normal astrocytes. The selective anticancer agent PB-100* inhibited these stimulatory effects. In addition, it could dose-dependently kill over 98% of the malignant cells while not affecting normal cells.
ABSTRACT: When past the stage amenable to surgery, melanoma and its metastases are, as a rule, treated with chemotherapy, which is largely unsuccessful. In this report, experimental evidence is presented demonstrating that, in vitro, two selective anticancer agents, PB-100 and BG-8, dose dependently destroy human G-361 melanoma cells, but do not affect human non malignant CCD-974Sk fibroblasts used as controls. Trace metal compounds, present, often in abnormal amounts, in the cancer cell and/or its environment, are known to influence its proliferation. Assays were carried out using highly elevated amounts of ferritin, iron chloride or zinc chloride. Ferritin proved differentially mitogenic for melanoma cells and fibroblasts. Its activity was inhibited by both anticancer agents, which however tended to become less efficacious in its presence. FeCl3 was more moderately, but equally, mitogenic for malignant and normal cells, yet it impaired antiproliferative activity of PB-100 and inhibited that of BG-8. ZnCl2 exhibited a selective antiproliferative activity on the malignant melanoma cells; it did not compete with PB-100 or BG-8. Specific recognition and destruction of malignant cells by the two anticancer agents are discussed.
ABSTRACT: Selective targeting to diseased cells, ensuring nontoxicity for normal cells, are the master words for anticancer and antiviral therapies. Yet little progress has been made on these lines and adverse side effects are still the rule. After having designed a rapid and simple in vitro screening test (Oncotest), we were able to find a number of plant derived, chemically well defined substances which selectively inhibit cancer cell multiplication without affecting normal cells. Activity of these agents is based on the fact that, as we discovered after extensive comparison of DNAs from cancer cells and their normal counterparts, cancer DNA is characterized by its highly relaxed, destabilized secondary structure, within which H-bond breakage is evidenced by 260 nm UV absorption, always distinctly higher than that of normal DNA. Our anticancer agent easily bind to the “open” cancer DNA chains; in contrast, they do not bind to normal DNA chains, which are “closed” most of the time.
ABSTRACT: Selectivity of the anticancer agent PB-100 for malignant cells, already demonstrated using cell growth and viability evaluation, is now confirmed by microscopic observations. PB-100 is easily detected inside cells by its yellow color under visible light and by its blue fluorescence; it may be measured in isolated nuclei using its characteristic UV absorbance. After short treatment of human BCNU-resistant glioblastoma cells (U 251) and normal astrocyte controls (CRL 1656), PB-100 accumulates in the malignant cell nucleus, particularly concentrating in the multiple nucleoli and rapidly inducing glioblastoma cell death, whilst, in contrast, the anticancer agent does not even enter normal cells. We had already shown that PB-100 binds to DNA of cancer cells, but not to that of normal cells. In vitro tests described in this report indicate that PB-100 binds to purine bases, but not to pyrimidines, of various ribopolymers and its binding to purine rich nucleic acid stretches is inferred.
ABSTRACT: Human skin fibrosis caused by radiotherapy contains very active ribonucleases (RNasas). This is probably connected with the appearance of postradiotherapy fibrosis. We prepared a highly purified extract of Ginkgo biloba golden leaves, which behaves as biological regulator. It normalizes to a large extent the excessive RNase activity in an extract of irridiated human skin cells, but does not affect activity of normal human plasma RNase. This extract may be used for this fibrosis treatment.
ABSTRACT: The multifunctional cytokine interleukin-6 behaves as a growth factor for various malignancies. It is produced in significant amounts by glioblastoma cells. When exogenous IL-6 is added (pg/ml) to culture medium of human glioblastoma cells and normal (non malignant) astrocytes used as controls, it exerts a dose dependent and differential effect on these two cell lines. Enhancement of cell proliferation is twice as high for glioblastoma cells as for astrocytes. In vitro, the novel anticancer agent PB-100 (mu g/ml) dose dependently inhibits this stimulatory activity. In addition, increasing PB-100 concentrations finally induce death of the malignant cells, yet do not impede multiplication of normal astrocytes. PB-100 does not abolish IL-6 production by cells, but keeps its level down to physiological values. PB-100 should therefore find its place in therapies requiring control of IL-6 production.
ABSTRACT: The multifunctional cytokine interleukin-6 behaves as a growth factor for various malignancies. It is produced in significant amounts by glioblastoma cells. When exogenous IL-6 is added (pg/ml) to culture medium of human glioblastoma cells and normal (non malignant) astrocytes used as controls, it exerts a dose dependent and differential effect on these two cell lines. Enhancement of cell proliferation is twice as high for glioblastoma cells as for astrocytes. In vitro, the novel anticancer agent PB-100 (mu g/ml) dose dependently inhibits this stimulatory activity. In addition, increasing PB-100 concentrations finally induce death of the malignant cells, yet do not impede multiplication of normal astrocytes. PB-100 does not abolish IL-6 production by cells, but keeps its level down to physiological values. PB-100 should therefore find its place in therapies requiring control of IL-6 production.
ABSTRACT: In vitro, when using low concentrations of ferritin (ng/ml) or CaCl2 (micrograms/ml), multiplication of a human, 1,3-bis-(2-chloroethyl)-1-nitrosourea (BCNU)-resistant glioblastoma cell line (U251) is enhanced 1.5 to 2 times more actively than multiplication of a normal astrocyte line (CRL 1656). Ferritin and Ca2+ ions exhibit a marked effect on DNA isolated from these cells: glioblastoma DNA relaxation is strongly increased (as evidenced by increased 260 nm ultraviolet absorbance), being from 5 to 6 times that of astrocyte DNA, which remains only slightly affected. Under identical experimental conditions, Zn2+ and gallium ions selectively inhibit glioblastoma cell multiplication but at the same concentrations do not inhibit astrocyte multiplication. Ultraviolet absorbance measurements demonstrate that both of these agents condense relaxed glioblastoma DNA in vitro. Zn2+ or gallium ions added to culture medium containing stimulatory concentrations of ferritin or Ca2+ ions selectively and strongly inhibit enhancement of glioblastoma cell multiplication by these mitogens while not affecting normal multiplication of astrocytes.
ABSTRACT: Major drawbacks to present-day cancer chemotherapy are its intrinsic lack of selectivity for tumour cells, resulting in severe damage to normal rapidly dividing cells, and the widespread emergence of drug resistance. Here experimental evidence is presented demonstrating that PB-100, a beta-carboline alkaloid, selectively inhibits in vitro multiplication of human BCNU-resistant glioblastoma cells (U251), but has no effect on normal astrocyte (CRL 1656) multiplication. PB-100 activity is dose-dependent. In the presence of ferritin or CaCl2, which are highly mitogenic for glioblastoma cells, higher doses of the alkaloid are required to inhibit multiplication completely. PB-100 is one of several compounds which were selected for their specific action on cancer DNA and cells, together with lack of activity on normal DNA and cells. Both the selectivity of PB-100 and its ability to overcome drug resistance stem from its effect on cancer DNA secondary structure. This activity is described and discussed, and therapeutic applications are mentioned..
ABSTRACT: Cell function and differentiation are the outcome of multiple and complex events. Information contained in the genes is transferred to the enzymes and machinery responsible for protein synthesis via sophisticated biochemical pathways, some of which, despite their intricacy, are now well documented. Conversely, genes receive information which modulates their activity. Many different molecules are able to bind to nucleic acids (deoxyribonucleic acid, DNA, and ribonucleic acid, RNA), thereby modifying gene activity as well as that of various enzymes connected with it. It is well established that the effect of endogenous or exogenous molecules on such fundamental processes of cell life as DNA duplication, transcription and translation may dramatically affect other biochemical processes both downstream and upstream. Binding of any molecule to DNA may influence cell life “for better or for worse”.
Deutsche Zeitschrift für Onkologie, 24, 2, 1992, pp. 41-46.
ABSTRACT: Radioprotector WR-2721 (S-2 (3-amino-propylamino)-ethyl-phosphorothioic acid) includes in vitro the contraction of DNA chains, but only when these originate from normal cells. Chain contraction results in a decrease of UV absorbance at 260 nm (hypochromicity). A correlation exists between DNA hypercromicity induced by WR-2721 and decrease in the synthesis of the same DNAs used as templates in the presence of this radioprotector. In contrast, the compound has no effect either on secondary structure of DNAs from various cancer cells or on in vitro synthesis of these DNAs. In association with R.L.B. which selectively prime replication of DNAs from normal haematopoietic cells, WR-2721, used at ralatively low doses, protects mice against lethal doses of gamma radiation. Efficient survival rates are obtained. The mechanism of this protection by WR-2721 and R.L.B. is discussed.
ABSTRACT: In 1970, with my group at the Pasteur Institute in Paris, I observed that showdomycin resistant Escherichia coli cells excrete into their culture medium a small RNA, about 160 nucleotides long, rich in purine bases. This RNA transforms wild bacteria (E. coli and Agrobacterium tumefaciens) into transformants which exhibit new stable biochemical and physical characteristics. Thus A tumefaciens once transformed by E. coli transforming RNA, partially or often totally loses its oncogenic potentialities and acquires new properties. It appeared that reverse transcriptase might give transforming RNA the means of integrating into the genome of the transformed organisms the modifications it vectored. We demonstrated (1971-1972) that bacterial reverse transcriptase was involved in this process. In the course of our studies on bacterial transformation, we devised a technique which led to the discovery, first of RNA free reverse transcriptase in bacteria, then of RNA-bound reverse transcriptase which is easily distinguishable from DNA-dependent-DNA-polymerase. In 1989 several american scientists rediscovered reverse transcriptase in E. coli.
ABSTRACT: Assays were carried out with short-chain RNA fragments in order to determine whether they can prevent or decrease chemotherapy-induced neutropenia and thrombopenia, as well as to evaluate side effects. We studied both first patients, 65 and 77 years old with non-Hodgkin lymphoma. The short-chain RNAs, administred bysublingual way every second day, appear useful in this indication. Neutrophils and platelets are significantly increased. In addition, tolerance of the RNA fragment is good and no side effect is observed. Chemotherapy protocols could be followed without treatment.
Available in French only.
ABSTRACT: La sélectivité d’action des substances est une notion aussi nouvelle que fondamentale. Alors que toutes les autres solutions jusqu’ici offertes sont brutales, toxiques (les médicaments s’incorporant souvent sans retour dans les gènes), est offert une alternative ciblée, de toute sécurité, multifocale afin que le virus soit détruit, l’immunité protégée et l’équilibre rétabli, seules conditions pour une vie de qualité se dirigeant jour après jour vers la “guérison”..
Deutsche Zeitschrift für Onkologie 5, 22, 1990, pp. 145-152.
ABSTRACT: Nous avons étudié l’effet des alcaloïdes : Alstonine, Serpentime et Sempervirine, en association avec la radiothérapie sur 5 patients ayant un carcinome prostatique. Ces résultats confirment ceux déja obtenus en laboratoire sur la reconnaissance sélective du DNA néoplasique.
ABSTRACT: About one third of patients with various malignant diseases were found to have extractable amounts of DNA in their plasma whereas no DNA could be detected in normal controls. Using the test established by one of us (M.B.), which is based on decreased strand stability of cancer cell DNA, we have found that several plasma DNA originate from cancer cells.
ABSTRACT: We have previously shown that DNA fom plant Crown-gall tumour tissues is highly relaxed and thereby very susceptible to various DNA-destabilizing agents which, in contrast, do not affect DNA from healthy tissues. In vitro DNA strand separation (chain unpairing), the rate of in vitro DNA synthesis and in vivo increase in tumor cell multiplication are colsely correlated. Here we report that plant non-tumour cell DNA may temporarily undergo conformational changes when these cells are cultured in vitro in the presence of opines (octopine, nopaline, lysopine which accumulate in Crown-gall tissues or dl-ethionine (a known carcinogen in mammalian tissues). The induced DNA double-strand destabilisation and consequent increase in template activity are shown to be reversible under our experimental conditions.
ABSTRACT: Purine rich small “RNA-primer” molecules (about 10-12 nucleotides), secreted into the growth medium of 3-h germinated conidia of N. crassa, strongly stimulated a concentration-dependent in vitro DNA synthesis of N. crassa slime mutant as well as DNAs from the human cancer cells but did not affect that from normal cells. These “RNA-primer” molecules stimulated also in vivo cell growth of N. crassa slime mutant, but not of the N. crassa wild type. Our studies suggest that DNAs from the slime mutant of N. crassa as well as DNAs from human cancerous cells provide increased sites for enhanced in vitro and in vivo replication of DNAs. “RNA-primer” molecules can be hydrolyzed by T1 RNase but not by pancreatic RNase.
ABSTRACT: Small quantities of carcinogens, dl-ethionine, thiotepa, actinomycin D, and 1-(2-chloroethyl-3-cyclohexyl)-1-nitrosourea (CCNU) stimulated in vitro deoxyribonucleic acid (DNA) synthesis of the slime mutant of Neurospora crassa, while there was practically no effect on the DNA from the normal wild type 74A strain. All of these compounds caused increased strand separation in the mutant DNA of N. crassa, but no separation of normal DNA strands. The growth (in vivo tests) of the N. crassa slime mutant, but not its wild type, was markedly increased when nontoxic concentrations of one of the carcinogens (dl-ethionine) tested were present in the growth medium. These observations suggest that, unlike the wild type N. crassa, the slime mutant allows an excessive and unscheduled replication, indicating destabilized nature of its DNA.
ABSTRACT: Terminal deoxyribonucleotidyl transferase (TdT) (EC 2.7.7.31) was defined as a template independent DNA polymerase that binds deoxyribonucleoside-5′-monophosphates (dNMP) in sequential addition to the 3’OH end of the DNA initiator. TdT may exhibit its activity in the presence of oligodeoxyribopolymers. This enzyme has been found in embryonic calf thymus gland, cortical thymocytes, brain, primitive bone marrow cells, peripheral blood lymphocytes in certain forms of acute leukemia, neuroblastoma and retroviruses. A model was proposed according to which TdT may generate somatic mutations in the variable region of immunoglobulin genes. Recently, the mutagenic potential of TdT has been evaluated: TdT inserts noncomplementary bases during repair synthesis by DNA polymerase. The present work shows that purified and commercially available hepatitis-B antigen (vaccine) contains a very active TdT and ribonuclease (RNase).
Médecines nouvelles, 15, 1986, pp. 57-86.
ABSTRACT: Various trigger molecules (carcinogens, antimitotics, antibiotics, hormones, etc…) may induce mammalian cancer DNA chain relaxation correlated with an in vitro increase of DNA synthesis and the enhancement of cancer cell multiplication in vivo. In contrast, particular substances which contract cancer DNA chains inhibit cancer DNA synthesis and prevent cancer cell multiplication in vivo. During cancer evolution, large amounts of α-feto-protein (AFP), carcinoembryonic antigen (CEA) and calcitonin, may be synthesized. AFP normally produced by liver cells may accumulate in breast cancer tissues or in induced inflammatory lesions; it favours the accumulation of estrone in the new-born rat brain and affects the multiplication of estrogen-sensitive cells. The aim of the present work was to determine the effect of some embryonic antigens (markers) on normal and cancer DNA chain relaxation and DNA in vitro synthesis, in order to investigate their participation in the maintenance of the neoplastic state in vivo.
ABSTRACT: Purified total DNAs were isolated from oncogenic or nononcogenic Agrobacterium tumefaciens cells as well as from normal and crown gall tissues. Opines (octopine, nopaline, lysopine), plant hormone (auxin IAA) and some carcinogenic compounds were used in order to correlate their effects on in vitro strand separation and synthesis of DNAs with in vivo tumorous cell multiplication. Octopine (or nopaline) induced chain opening of DNAs originating from octopine (or nopaline)-metabolizing bacteria and from same bacteria strain-induced tumorous cells. This phenomenon was measured by the increase in DNA hyperchromicity which is concentration dependent. The tested compounds stimulated the in vitro synthesis of the same DNAs. Under the same conditions, in vitro strand separation and synthesis of healthy plant DNA was not (or only slightly) enhanced, except in the case of particular hormone-connected healthy cell DNA. IAA and carcinogens stimulated in vitro synthesis and induced in vitro strand separation (dose-dependent effect) of DNAs isolated from crown gall cells and inducing bacteria. Compared to healthy cell DNAs, these DNAs were thus susceptible to structurally very diversified molecules and in this way behave as do mammalian tissue DNAs. The opine and IAA actions observed here were specific for plant tissue DNA; cancerous human or animal tissue DNAs were insensitive. By their presence in the crown gall cells, opines possibly maintain destabilized areas (required for rapid growth and division) on tumor cell DNA. The cooperative actions of IAA and opines as well as small RNA and RNA fragments on gene activation, might explain the autonomy of plant tumor cells..
ABSTRACT: The growth of Crown-gall cells cultures in vitro (Nicotiana tabacum L. cv. White Burley and Parthenocissus tricuspidata cv. Veitchii) is inhibited by alstonine (BG-8), a plant alkaloid, the anti-cancer effect of which has previously been demonstrated on animals and plants. The growth of normal cells is only slightly affected. The inhibitory effect of BG-8 on crown-gall cells is antagonized byindole-3-ecatic acid (IAA) added to the culture medium. Kinetin associated with IAA does not prevent this inhibitory effect. BG-8 present in the culture medium containing the two types of hormones seems to modify the later hormonal requirement of Parthenocissus crown-gall tissues…
ABSTRACT: Most of the anti-cancer drugs at present used in cancer chemotherapy exhibit tissue toxicity and cause severe damage to harmatopoietic cells. In addition, they are mutagenic and/or carcinogenic in animals and in plants. Using the Oncotest, we have selected three alkaloïds, alstonine, serpentine and sempervirine that possess the capacity to sistinguish in vitro between DNAs isolated from cancerous and healthy mammalian and plant tissues. They bind to the initiation sites of destabilized cancer DNA synthesis, without affecting that of DNAs from healthy tissues. Here we demonstrate that each of the three alkaloïds, which remain inactive against normal eukaryotic cells, selectively and completely destroys the proliferative potential of various established cancer cell lines maintained in and in vitro culture.
ABSTRACT: This monograph explores basic processes of DNA replication and transcription in an effort to identify the mechanisms responsible for the release of genetic information and its role in the regulation of cellular events.
ABSTRACT: Tumor promoters accelerate the proliferative capacity of tumor cells although at high concentrations they may induce carcinogenesis in animals. Recently it was shown that TPA, (12-0)trtradecanoyl-phorbol-13-acetate), the tumor promoting phorbol ester, appears to act in a similar fashion on normal embryonal diploid and cancer cells. TPA induces differentiation of leukemic cells, activetes silent genes for specific r-RNA synthesis in hybrid cells and promotes cell proliferative capacity or phenotypic cellular changes. Here we report the in vitro effect of TPA on DNA secondary structure and DNA in vitro synthesis.
ABSTRACT: Using a biochemical assay system (Oncotest) we have shown that DNAs from cancerous mammalian and plant cells are destabilized compared to DNA from healthy cells. Cancer DNAs susceptible to the action of carcinogens or other different compounds exhibit in vitro and in vivo a high template activity in comparison to DNAs from healthy cells. We have also shown that alstonine, a plant alkaloïd prepared in our laboratory which selectively binds to DNA from cancer cells prevents DNA in vitro synthesis as well as cancer cells in vivo multiplication in animals and plants. It has slight effect on DNA from healthy cells. We describe here the effects of auxin (IAA) and kinetin (K) (two cell growth and division hormones in higher plant species) and that of alstonine (BG-8) on in vitro synthesis and strand separation of DNAs isolated from cancerous, habituated and healthy plant cells cultures in vitro.
ABSTRACT: The high template in vitro activity of native DNA from cancerous mammalian and plant tissues, compared to DNA from healthy tissues, enabled us to select substances which selectively inhibit cancer DNA synthesis. Among them, alstonine, serpentine, sempervirine and flavopereirine, all alkaloids which belong to the Beta-carboline class, distinguish cancer DNA from healthy tissue DNA inhibit DNA in vitro synthesis when native DNA from different cancerous tissues or cells is used as template. They have practically no effect on DNA from healthy tissues. The inhibitory effect of alkaloids is due to their capacity to form an ‘alkaloid-cancer DNA’ complex which has been characterized by use of the Sephadex column. Evidence is presented showing that these alkaloids inhibit the initiation of DNA synthesis but not chain elongation. The stimulating action caused by carcinogens during cancer DNA in vitro synthesis may be prevented and reversed by alkaloids. Furthermore, the stimulating action of steroids during in vitro synthesis of hormone target tissue DNA might be neutralized by alkaloids. However, at relatively high doses, steroids reversibly compete with alkaloids for binding sites on breast cancer DNA. This is not observed with DNA from nonhormone target tissues.
ABSTRACT: The effects of the carcinogen dimethylbenz (a)anthracene, of antimitotic drugs (cyclophosphamide and daunorubicin), of the plant hormone (auxin IAA) and the antimitotic mitomycin C were investigated in vitro on cancer and healthy DNA from pea seedings, inoculated or not, with oncogenic agrobacterium tumefaciens. These substances stimulate in vitro both synthesis and strand separation of Crown-gall DNA as well as oncogenic A. tumefaciens DNA, while they have little effect on normal plant DNA as is the case with E.coli and non-oncogenic A. tumefaciens DNA. This correlates with the substance-enhancing-power on in vivo Crown-gall cell multiplication. Growth-stimulatory or inhibitory-effects are antagonized by the tumorless action of E. coli small size RNA-fragments. Plant ribonuclease is under control of all these compounds and the RNA-fragments compensate for increased or decreased ribonuclease activity induced by cyclophosphamide, daunorubicin, dimethylbenz(a) anthracene or auxin. There appears to be a correlation between ribonuclease activity and Crown-gall cell development.
ABSTRACT: Based on the differential template activity exhibited by DNA isolated from cancerous and healthy human or animal tissues, the Oncotest is an accurate and rapid assay for the screening of carcinogenic compounds. Thus, in the presence of all necessary components for radioactive DNA synthesis by DNA polymerase, carcinogenic compounds, antimitotic drugs (and miscellaneous compounds), at given concentrations strongly stimulate the synthesis of DNA isolated from different cancer tissues, but only slightly enhance that of DNA from healthy tissues. Those carcinogens which cannot be characterized as mutagens in the Salmonella assay system, behave as carcinogens in the Oncotest. Carcinogenic potential of steroids can be shown by using the DNA from steroid hormone target tissue. There exists a common molecular mechanism through which carcinogens stimulate cancer DNA in vitro synthesis. Cancer DNAs are destabilized and in the presence of carcinogenic substances there is further DNA strand separation which accounts for the enhanced DNA synthesis. A correlation between in vitro cancer DNA synthesis, DNA strand separation and in vivo multiplication of cancerous cells can be demonstrated. Our assay system allows to detect those substances which selectively inhibit cancer DNA synthesis without affecting, in an appreciably way, that of DNA from healthy tissues.
ABSTRACT: The leukopoietic activity of Beljanski leukocyte restorer(s) (BLR(s)) (RNA-fragments obtained from Escherichia coli rRNA), E; coli endotoxin, and hydrocortisone administrated iv was compared in rabbits treated daily with high doses of cyclophosphamide (CP), a drug which decreases the circulating leukocyte count. Results showed that endotoxin and hydrocortisone responses, characterized essentially by granulocytosis occured at the 48th hour and remained, even during daily CP administration, within physiological limits for 3-5 days. No tolerance was induced with by administration of BLR in normal rabbits, even after 11iv injections, implying no depletion of bone marrow cells. In contrast, repeated endotoxin injections led to febrile and leukocytic tolerance. In addition, BLR induced normal leukocytosis and a biphasic fever response in endotoxin-tolerant animals. When BLR and endotoxin were mixed and administrated every day to rabbits, the animal became tolerant to endotoxin but gave a normal fever and leukocyte response to BLR, even after the 14th injection. The imbalance induced by CP administration in the granulocyte/lymphocyte ratio may be corrected following an injection of BLR. These data showed that the physiological activity of BLR in leukopoiesis was clearly distinguishable from that manifested by E. coli endotoxin and in the second instance by hydrocortisone.
NB : today, these extracts are named Realbuild
ABSTRACT: The chemicals 9, 10-dimethylbenzanthracene (DMBA), ethionine, daunorubicin, actinomycin D, 1-(2-chloroethyl-1)-nitrosourea (CCNU), steroids, croton oil and dimethyl-sulfoxide (DMSO) were used in order to correlate their effect on the in vitro synthesis of normal and cancer DNA, on DNA strand separation and on accelerated in vivo multiplication of cancer cells. All of the compounds tested strongly stimulate the synthesis of cancer DNA in vitro catalyzed by DNA-dependent DNA polymerase I and measured as an acid-precipitable labeled product. Under the same conditions, the synthesis of DNA originating from healthy tissues is only slightly enhanced, except in the case of croton oil and DMSO. These substances are almost equally active on cancer and normal DNA. Although both cancer and normal DNA contain a large amount of double-stranded regions, the extent of DNA strand separation measured by the increase in UV absorbance (hyperchromicity) in the presence of each compound tested is much higher for all cancer DNA than for corresponding normal DNA. In contrast, DMSO and croton oil do not appear to distinguish cancer DNA from normal DNA. Additive and differential effects of various compounds on cancer DNA strand separation can be observed. Small doses of DMBA and CCNU stimulate the multiplication of Ehrlich ascites tumor cells in vivo in mice. There is thus a possible correlation between DNA strand separation, DNA synthesis, multiplication and differentiation of cancer cells in the presence of the above compounds, which is different from the response of normal cells to these compounds.
In the Role of RNA in Development and Reproduction.
NCI-EORTC Symposium on nature, prevention and treatment of clinical toxicity of anticancer agents.
Institut Bordet, Bruxelles, 1980
ABSTRACT: Parallel studies on plant and animal tumor sytems provide insight into the basic cellular mechanisme of tumorogenesis. In the laboratory animals, drugs characterized as mutagens with the Salmonella assay system, as for example cyclophosphamide, may have an antimitotic effect and/or give rise to neoplasms. Various other in vitro carcinogen screening tests have shown that cyclophosphamide and daunorubicin have mutagenic and carcinogenic potencies. We give here a brief summary of the effect of two anticancer drugs, cyclophosphamide (Endoxan) and daunorubicin, on the heritable cellular change in pre-induced Crown-gall tumor development.
ABSTRACT: We describe a very rapid, sensitive and economic assay system (Oncotest) using purified DNA(s) from both cancerous and healthy human tissues (lung, breast, ovary and brain) and DNA dependent-DNA polymerase I, partly purified from Escherichia coli for detecting potential carcinogens. The amount of in vitro synthesized radioactive DNA as acid precipitable product is measured under strictly identical experimental conditions in the absence or presence of various concentrations of coumpounds to be screened. All known carcinogens and several drugs we tested strongly stimulate the syntheses of cancer DNA and only slightly that of DNA from healthy tissues. The results can be obtained within 1 to 4 hours.
ABSTRACT: Under well-defined conditions, ribosomal RNA from Escherichia coli is fragmented by pancreatic ribonuclease, leading to the appearance of particular RNA fragments. Some of these fragments act as primers for in vitro replication of DNA extracted from blood-cell and platelet-forming tissues. In experimental rabbits they restore in a rapid and harmless way normal circulating leukocyte and platelet levels when these have been drastically decreased by various chemotherapeutic agents mainly used in anticancer therapy. Imbalance between polynuclear and lymphocyte count provoked in rabbits by cyclophosphamide can be rapidly corrected by treating the animal with active RNA fragments.
ABSTRACT: When ribosomal RNA which contains an excess of purine nucleotides is subjected to mild degradation by a specific ribonuclease, we can isolate specific RNA-fragments which, in vitro, can be described into complementary DNA by an RNA dependent DNA polymerase partially purified from Escherichia coli extracts. These RNA-fragments can either stimulate or inhibit development of crown-gall tumors induced by inoculation of Agrobacterium tumefaciens (oncogenic strain B6) into decapitated germinating pea seedlings (Pisum sativum L cv. Annonay). Stimulation or inhibition of tumor development depends on the time at which the RNA-fragments have been introduced into the bacteria-infected wound. Interaction between RNA-fragments and auxin was also studied. Results obtained both in vitro and in vivo will be described.
ABSTRACT IN FRENCH : Lorsque les taux de leucocytes et de plaquettes dans le sang ont été abaissées par l’effet secondaire de certaines chimiothérapies, ces taux peuvent être ramenés rapidement et sans danger à leurs valeurs normales par les ARN-fragments, les R.L.B.
ABSTRACT IN ENGLISH : When the leucocytes and blood platelets have their counts reduced in the blood following chemotherapy, they can be rapidly and safely, restored to normal values by injecting cellular ARN fragments, which the authors call R.L.B. factors.
ABSTRACT: Under well defined conditions ribosomal RNAs purified from Escherichia coli can be degraded by ribonuclease U2 giving rise to RNA fragments of 60-70 nucleotides. In vitro, these fragments are efficently transcribed into a complementary DNA by DNA polymerase RNA dependent, partially purified from extracts of E. coli. In vivo, “RNA-fragments-U2” inhibit the development of plant tumors.
Documents not available online
ABSTRACT: Evidence indicating the presence of a RNA-bound RNA-dependent DNA polymerase (RDDP) in the eukaryotic fungus Neurospora crassa is presented. This enzyme, free of DNA-dependent DNA polymerase, is capable of synthesizing DNA only in the presence of all four deoxyribonucleoside 5′-triphosphates and Mg2+. The DNA polymerase activity is decreased considerably if the RNA bound to the enzyme is eliminated. The activity can be restored by addition of some particular RNA but not by addition of DNA. Both template RNA and the synthesized DNA product sedimented on sucrose density gradients are approximately 6 S. RNA-bound RNA-dependent DNA polymerase partially purified from extracts of N. crassa was distinguishable from known DNA-dependent DNA polymerases. DNA synthesized by RDDP was acid-precipitable and complementary to enzyme-bound RNA.
ABSTRACT: Particular RNA fragments obtained by action of pancreatic ribonuclease on purified RNAs originating from species totally unrelated to Agrobacterium tumefaciens (Escherichia coli, rabbit, monkey) are capable if inducing the formation of transplantable tumorous tissue when introduced at wounded sites in inverted stems of Datura stramonium maintained under axenic conditions on a medium containing auxin and kinetin. Reovirus RNA and a small size RNA (5-6 S) isolated from RNA bound RNA directed DNA polymerase from Escherichia coli also induced the appearance of tumorous tissues which grow on solid synthetic medium in the absence of auxin and kinetin.
ABSTRACT: Les ARN-fragments riches en nucléotides G et A déclenchent en présence d’ADN polymérase ADN dépendante I, la réplication de l’ADN circulaire simple chaîne du phage ΦX 174 en double chaîne ou forme réplicative ainsi que celle de l’ADN du pahge λ.
ABSTRACT: Parmi plusieurs ARN-fragments isolés après dégradation des ARN ribosomiques (E.coli M500 Sho-R), seuls certains de ceux obtenus par l’action de la ribonucléase pancréatique inhibent complètement chez le lapin la multiplication des virus du fibrome de Shope et la vaccine, sans compromettre la vie de l’animal.
ABSTRACT: Les ARN-fragments obtenus par dégradation ménagée des ARN ribosomiques (E. coli K12) en présence de ribonucléases, agissent avec une certaine spécificité comme amorceurs dans la réplication in vitro des ADN d’origines différentes. Ces résultats rendent possible de prévoir dans une large mesure l’action éventuelle des ARN-fragments particuliers dans le processus de la réplication in vivo des ADN. L’introduction dans une cellule déréglée d’ARN-fragments exogènes pourrait permettre à cette cellule de retrouver sa physiologie normale.
ABSTRACT: The fact that TI-RNA was found to be present in oncogenic and non-oncogenic strains of A. tumefaciens suggests that it is not released in biologically active form from the non-oncogenic strains and that the oncogenic strains have some special mechanisms for introducing the TI-RNA into host cells that is not possessed by the avirulent strains.
ABSTRACT: RNA-bound reverse transcriptase can be easily distinguished from RNA-free reverse transcriptase and DNA-dependent DNA polymerase after fractionation of extracts from Escherichia coli on a DEAE-cellulose column. This enzyme is capable of synthesizing a DNA-like product in the absence of exogenously added template provided that all four deoxyribonucleoside 5′-triphosphates are present in the incubation mixture. Removal of RNA from the enzyme by RNase leads to a considerably decreased polymerizing activity. The activity can be restored under appropriate conditions either by RNA originating from the enzyme or by transforming RNA excreted by showdomycin-resistant E. coli. Enzyme-bound RNA has several characteristics already found for the transforming RNA. DNA synthesized by RNA-bound reverse transcriptase is complementary to the enzyme-bound RNA.
ABSTRACT: Two RNA fractions have been isolated and purified from both oncogenic and nononcogenic strains of Agrobacterium tumefaciens. Both RNAs are capable of inducing the formation of transplantable tumors when introduced at wound sites in stems of Datura stramonium plants. One of these RNA fractions was found to be bound to an RNA-directed DNA polymerase, while the other was associated with the bacterial DNA. Physical evidence suggests that both are single stranded and small in size; linear sucrose gradients show that their size corresponds to a value of 5-6 S. A concentration of 4-5 ug of the RNAs dissolved in 0.01 ml of water is effective in initiating the formation of transplantable tumors in Datura plants.
ABSTRACT: Nous montrons ici que, in vitro, la PNPase des bactéries sauvages d’E. coli synthétise à 70° un ARN (ARN-70°) que l’ADN polymérase ADN dépendante d’origine bactérienne utilise comme amorceur pour la synthèse des nouvelles chaînes d’ADN.
ABSTRACT: Attempts were made to approach the mechanism by which the transfer of information is carried by transforming RNA from Escherichia coli. Transforming RNA, capable of inducing inherited changes in recipient cells, is used in vitro as a template by two distinct enzymes which mediate the transfer of information from RNA to RNA and DNA respectively. Using transforming RNA as a template, polynucleotide phosphorylase insensitive to rifampicin, synthesizes a product which was characterized as being a “copy” of template RNA. Reverse transcriptase, which can be physically separated from DNA polylerase, transcribes the transforming RNA into a complementary DNA product. According to hybridization experiments, DNA from Agrobacterium tumefaciens transformed by E. coli transforming RNA seems to contain one or less than one copy of complementary DNA.
ABSTRACT: Nous démontrons ici que la transcriptase inverse, aisément séparable de l’ADN polymérase ADN dépendante chez E. coli sauvage ou mutant sho-R, se trouve sous 2 formes : libre et associée à un ARN. L’ADN synthétisé par la transcriptase inverse a été analysé.
ABSTRACT: Nous décrivons ici certaines altérations observées chez les cellules KB après traitement par la showdomycine.
ABSTRACT: Nous avons cherché les conditions permettant de mettre en évidence l’existence d’une transcriptase de l’ARN en ADN chez E. coli K12 Hfr car ces bactéries possèdent des ARN transformants capables de provoquer chez les bactéries de diverses espèces l’apparition de nouvelles propriétés physiologiques et biochimiques stables, telle, chez Agrobacterium tumefaciens, la perte du pouvoir oncogène. Les résultats de ces recherches sont résumés dans cette publication.
ABSTRACT: Transforming RNA excreted by showdomycin-resistant Esherichia coli induces a persistent, heritable, and spectacular change in Agrobacterium tumefaciens B6, a bacterium that carries the oncogenic principle for tumor induction in plants. Transformants possessing new physiological and biochemical properties have completely or partially lost the capacity for tumor induction. They synthetize new ribosomes whose components are profoundly modified. On the basis of biological and biochemical characteristics, one is inclined to consider the completely transformed Agrobacterium tumefaciens as a “new species”.
ABSTRACT: Nous démontrons que des ARN “transformants” sont excrétés par des mutants qui ont la particularité de synthétiser les ARN intracellulaires riches en bases puriques. Les ARN excrétés transforment irréversiblement les bactéries sauvages en descendants qui pour l’essentiel ne se distinguent plus des mutants dont proviennent ces ARN à potentiel génétique.
ABSTRACT: Nous montrons ici qu’in vitro la PNPase des bactéries sauvages utilise comme matrice un ARN porté par l’ADN (épisome à ARN) de ces mêmes bactéries ainsi que l’ARN transformant excrété par les bactéries showdomycino-résistantes. Les caractéristiques de ces ARN ont été précédemment décrites.
ABSTRACT: In a mutant of Escherichia coli resistant to showdomycin, both the 50S and 30S ribosomal subunits contain RNA species in which the purine concentration greatly exceeds that of pyrimidines. The same is true for total rapidly-labeled RNA. The modified ribosomal RNA hybridizes poorly with homologous DNA, which is apparently unchanged in base composition. Acrylamide gel electrophoresis of mutant ribosomal proteins shows a highly altered protein pattern for both ribosomal subunits, although the activity of these ribosomes is not decreased.
ABSTRACT: Showdomycin, even at concentrations which do not affect bacterial growth, causes in E. coli, B. cereux and A. faecalis, a massive biosynthesis of rapidly labelled RNAs, which are no longer complementary to DNA. In addition in E. coli, the more thoroughly investigated organism, even non-inhibitory concentrations of the antibiotic provoke the synthesis of ribosomal 23 S RNA with a base ratio very different (excess of A and G nucleotides), from that of 16 S RNA and 4 S RNA. A similar change in RNA composition is observed in a showdomycin resistant mutant of E. coli, the growth rate of which is not lower than that of the wild type. RNA polymerase DNA dependent from the mutant has a very reduced specific activity; polynucleotide phosphorylase from the same mutant has new properties. Polynucleotide phosphorylase could in vivo be responsible for the synthesis of the modified RNAs.
ABSTRACT: Les faits présentés ici montrent que la showdomycine à faible dose fait apparaître chez plusieurs espèces bactériennes des ARN à marquage rapide (ARN-mr) nouveaux, et par son effet mutagène puissant transforme irréversiblement les bactéries d’E. Coli, leur conférant de nouvelles propriétés.
ABSTRACT: Nos résultats présentés ici montrent clairement que sans modifier la synthèse et la structure primaire de l’ADN on peut induire les cellules Escherichia Coli à synthétiser deux types d’ARN (ARN à marquage rapide et ARN ribosomique 23 S) dont la structure primaire diffère profondément de l’ADN.
ABSTRACT: Les résultats présentés ici montrent les caractéristiques d’un ARN matriciel 5,5 S présent dans une fraction d’ARN d’Alcaligenes f. qui contient des ARN dont les coefficients de sédimentation varient de 3,8 à 7,0 S. Nos données permettent d’affirmer que l’ARN matriciel diffère indiscutablement du ARN de transfert et du ARN ribosomal.
ABSTRACT: A new method for purification of “polypeptides synthetase” from Alcaligenes faecalis is described in which nucleic acids are removed by purification on DEAE-cellulose with a recovery of 60-75% of the initial enzymatic activity.
ABSTRACT: Une méthode nouvelle de purification des polypeptide-synthétases à partir d’extraits d’Alcaligenes faecalis permet d’obtenir à rendement élevé des préparations enzymatiques substantiellement purifiées.
ABSTRACT: Un acide aminé donné, attaché par les polypeptide-synthétases à des ARN d’origine différente (Alcaligenes f., E. coli, TYMV) est lié à un même nucléotide spécifique dans les di- et trinucléotides isolés. Les polypeptide-synthétases peuvent directement reconnaître à la fois chaque acide aminé et les sites (triplets) dans l’ARN que nous proposons dorénavant d’appeller ARN matriciel.
ABSTRACT: Asiaticoside, asiatic and madecassic acids affect the binding of L-14V-proline and L-14C-alanine to m-RNA in the presence of any one of the four nucleoside triphosphates and a partially purified bacterial enzyme preparation whose properties have been previously described. The binding of proline to m-RNA, but not its turnover, is inhibited by any one of the triterpenes used, while that of alanine is highly increased only by free asiatic acid. This latter inhibits the turnover of alanine bound to m-RNA thus shifting the reaction towards an accumulation of the “m-RNA-alanine” complex which is an intermediate in the synthesis of oligopeptides in the present system. The binding of L-amino acids to t-RNA in the presence of ATP is not affected by triterpenes. A hypotesis is proposed to account for the effect of triterpenes in mammalian cells in connection with biosynthesis of collagen, a protein rich in proline, hydroxyproline and alanine.
ABSTRACT: Résultats concernant la formation du complexe entre les acides L-acides aminés 14C et l’ARN purifié, isolé du virus de la mosaïque jaune du Navet.
ABSTRACT: L’ARN actif a le rapport des bases proche de celui de l’ADN d’Alcaligenes faecalis et possède donc cette caractéristique de l’ARN messager. Résultats concernant recherches.
ABSTRACT: Présentation des résultats qui permettent de préciser les propriétés et la nature de la fraction d’ARN capable d’accepter les L-acides aminés.
ABSTRACT: English summary : The formation of peptides in the presence of ribonucleoside-5′-triphosphates and of polypeptide synthetases from Alcaligenes faecalis requires the participation on an RNA fraction. Active RNA obtained from these bacteria has been identified by several procedures as being messenger RNA and has been partially purified by ammonium-sulfate fractionation. This RNA fraction has the ability to fix un-competitively L-amino-acids, forming a “RNA-AA” complex which, when isolated and incubated again in Tris buffer without the addition from various origins, acts as an amino-acids acceptor in the presence of Alcaligenes faecalis enzymes.
ABSTRACT: Des enzymes purifiés d’Alcaligenes faecalis forment des peptides à partir d’acides aminés libres en présence d’une fraction d’ARN. Cet ARN accepte tous les L-acides aminés “activés” en présence de chacun des quatre ribonucleoside 5′-triphosphates; le complexe “acide mainé-ARN” a été isolé. La fraction d’ARN actif fut identifié comme ARN à marquage rapide, mélange d’ARN messager et d’ARN éosomal. Les analogues de bases, incorporés dans cette fraction modifient sa capacité à fixer les acides aminés.
ABSTRACT: In this paper we present evidence showing that an RNA fraction is required for amino dependent release of P1 from ribonucleoside triphosphates and for peptide synthesis. We also report the finding that in the presence of the enzymes and nucleoside triphosphates C14-amino acids become linked covalently to the RNA fraction.
ABSTRACT: Les polypeptide synthétases purifiées à partir d’extraits d’Aclaligenes faecalis possèdent la capacité de synthétiser in vitro différents peptides à partir d’un ou de plusieurs acides aminés en présence soit d’ATP, GTP, UTP ou de CTP. Un groupe spécifique de L-acides aminés permet la dégradation de chacun des quatre ribonucléoside triphosphates en ribonucléoside diphosphate et en phosphore minéral. La stoechiométrie de la réaction est établie. La composition de certains peptides formés est déterminée par les méthodes chimiques et enzymatiques.
ABSTRACT: Les résultats rapportés dans la présente Note montrent la présence de polypeptide-synthétases dans les préparations particulaires et “l’enzyme pH5” obtenues à partir du foie de Rat. Le GTP pouvant être indirectement utilisé pour la formation de liaisons peptidiques, il est ainsi possible d’expliquer son rôle de facteur indispensable dans différents systèmes permettant l’incorporation des acides aminés dans les protéines.
Document not available online
ABSTRACT: Conclusion of conference : Les enzymes que nous avons isolé et purifiés à partir d’Alcaligenes faecalis sont capables de catalyser en présence d’acides aminés la dégradation des quatre ribonucléosidetriphosphates en orthophosphate et nucléosidediphosphates. Chacun des quatre enzymes est spécifique non seulement d’un type de nucléotide, mais également d’un groupe d’acides aminés. Ces enzymes possèdent le pouvoir de distinguer les acides aminés entre eux. Le processus de libération de l’orthophosphate s’accompagne de la formation de liaisons peptidiques. Une multitude de peptides, combinaisons variées, peuvent être formés par ces systèmes enzymatiques. Les peptides contenant un seul acide aminé peuvent également être formés. Par le mécanisme que nous venons de voir ces enzymes fournissent à partir de ribonucléosidetriphosphates les nucléosidediphosphates qui sont d’excellents substrats pour la polynucléotide-phosphorylase, enzyme capable de synthétiser les acides ribonucléiques. Ces observations suggèrent qu’un lien étroit existerait dans le fonctionnement et l’équilibre entre ces deux systèmes enzymatiques en particulier. Nous revenons à l’idée que des précurseurs communs peuvent être formés et utilisée dans la biosynthèse des protéines et des acides ribonucléiques c’est-à-dire des ribonucléoprotéines constituant majeur des cellules de différentes espèces.
ABSTRACT: A highly purified preparation of the “amino acid incorporation enzyme” is capable of catalysing the transfer of phosphate from triphosphonucleosides to homologous diphosphonucleosides (ATP-ADP; UTP-UDP; CTP-CDP; GTP-GDP). Thermal inactivation ot this enzyme preparation suggerst the existance of four differnnt and specific enzymes each capable of catalysing the Mg++ dependent exchange of one pair of nucleotides. The purified enzymic preparation is free of diphosphonucleoside kinase (ATP+UDP<=>UTP+ADP), monophosphonucleoside kinase (ATP+UMP<=>ADP+UDP) and myokinase (2 ADP<=>ATP+AMP)
ABSTRACT: The incorporation of 14C amino acids into protein by Alcaligenes faecalis fragments has been demonstrated. Using 14C valine, it was found that most of the incorporated amino acid was within the peptide chains. Alcaligenes fragments have been partially solubilized by treatment with perfluoro octanoate without affecting the incorporation activity. The soluble fraction obtained after this treatment can be replaced by purified “amino acid incorporation enzymes”.
ABSTRACT: Une fraction enzymatique EAA obtenue et purifiée à partir d’Alcaligenes faecalis possède la capacité d’activer l’incorporation des acides aminés dans des fragments subcellulaires de ces mêmes bactéries. Toutefois, elle semble incapable d’activer l’échange entre le PP et l’ATP en présence d’acides aminés, mais catalyse le transfert de l’orthophosphate entre les nucléosides-triphosphates et les nucléosides-diphosphates homologues.
ABSTRACT: L’ensemble de ces résultats montre que la fraction EAA, par ses quatre réactions d’échange diffère de la synthétase du glutathion qui, ainsi que nous l’avons observé, n’échange que l’ATP avec l’ADP. Ceci explique aisément l’incapacité de la synthétase du glutathion à remplacer notre fraction enzymatique EAA pour l’incorporation des acides aminés. En revanche in est remarquable de constater qu’un système enzymatique impliqué dans l’incorporation d’un grand nombre d’acides aminés se montre capable d’activer le transfert du phosphore entre les quatre principaux nucléotides. Il est difficile de ne pas supposer qu’il y ait une association nécessaire entre cette activité phosphotransférasique et l’activité responsable de l’incorporation des acides aminés.
ABSTRACT: Indications have been obtained for the presence ot the amino acid incorporation enzyme in the supernatant fraction from rat liver and in the precipitate obtained by acidification of this fraction to pH 5.2 (pH 5 enzymes). Highly purified amino acid incorporation enzyme from A. faecalis completely replaces the pH 5 enzymes in stimulating the incorporation of C14-leucine into protein of rat livermicrosomes. These observations show that the amino acid incorporation enzyme is involved in protein biosyntheses of both mammalian and bacterial cells.
Highly purified preparations of the A. faecalis incorporation enzyme catalyze a rapid, Mg++dependent exchange a radioactive ADP with ATP an activity which appears to be related to their amino acid incorporation activity. This finding may be of significance, since glutathione synthetase, which catalyzes the synthesis of a typical peptide, brings about a similar exchange.
Discussion not available online
ABSTRACT: Particulate preparations of Alcaligenes faecalis, consisting largely of cell membrane fragments, incorporate amino acids into their proteins. This incorporation, which appears to reflect protein biosynthesis, is driven by oxidative phosphorylation and is stimulated by an enzyme, present in the supernatant extract, which has been isolated in highly purified form. The purified enzyme is free of activating enzymes catalyzing the amino acid-dependent exchange of PP32 with ATP and the same seems to be true of the bacterial particles.
ABSTRACT: Dans le présent mémoire nous décrivons les propriétés d’un mutant d’Escherichia coli obtenu par sélection en présence de streptomycine. Ce mutant est caractérisé par la streptomycino-résistance et par l’incapacité de synthétises l’hemine.
ABSTRACT: Molecules containing porphyric groupe do not influence the photo-restoration of E. Coli strains studied by the authors. In consequence, in the case of these strains : a) The porphyrins do not appreciably act as chromophores in the photo-restoration process. This fact should be discussed as soon as a sufficiently precise action spectrum of light on E. Coli will be available. b) The catalase and peroxydase enzymes do not appreciably participate in the photo-restoration process, which remains indefinite. We can only state that this process does not apply to lesions due to the activity of photo-formed peroxydes. So it seems that photo-restoration is very different from restoration by catalase, which is an essentially peroxydase process.
ABSTRACT: On peut obtenir l’apoenzyme de la catalase sous forme d’extraits solubles à partir du mutant H7 d’Escherichia coli, auxotrophe pour l’hémine, dépourvu d’activité catalasique. L’addition d’hémine à l’apoenzyme permet la reconstitution in vitro de la catalase active. Le mutant isolé permet d’effectuer une résolution “physiologique” de la catalase.
Document not available online : “Photorestoration in porphyrin-less mutants of Escherichia coli”
Document not available online : “Formation d’enzymes respiratoires chez un mutant d’Escherichia coli streptomycino-résistant ne manifestant pas d’activité respiratoire”
ABSTRACT: Le mutant H7 diffère du type normal par la perte du pouvoir de synthétises l’hémine. L’étude de ce mutant doit permettre de déterminer quels sont, chez E. coli, les systèmes enzymatiques dont la synthèse et l’activité sont liées directement ou indirectement à la présence du groupement héminique. L’étude de l’action très marquée de l’hémine sur la formation de l’hydrogénase pourrait apporter une confirmation expérimentale à l’hypothèse que cet enzyme possède un groupement héminique.
ABSTRACT: Nous avons observé une forte incorporation du clycocolle radioactif dans les protéines de Micrococcus lysodeikticus non lysé et lysé avec du lysozyme en présence de saccharose. La ribonucléase dégrade l’acide ribonucléique des lysats et supprime presque totalement l’incorporation du glycocolle dans les protéines. Elle n’agit pratiquement pas sur les suspensions bactériennes intactes. La désoxyribonucléase stimule notablement l’incorporation du glycocolle dans les protéines des lysats, tout en dégradant l’ADN de ces derniers; elle active leur respiration. Cet enzyme ne semble pas avoir d’action sur les suspensions bactériennes intactes. L’ATP ajouté comme source d’énergie diminue l’incorporation du glycocolle. Comme transporteur de phosphate, il n’agit pas sur la synthèse protéique. Deux hypothèses sont envisagées afin d’essayer d’expliquer l’effet stimulant de la désoxyribonucléase sur l’incorporation du glycocolle dans les protéines des lysats en présence de saccharose.
ABSTRACT: D’après ces travaux, nous étions en mesure de penser que la streptomycine ajoutée à une culture bactérienne, était capable d’empêcher l’assimilation normale des métaux par les bactéries et agissait ainsi indirectement sur les systèmes des oxydases et des deshydrogénases. Elle créerait donc un nouvel équilibre dans la répartition des métaux utilisés par la souche résistante pour sa prolifération. cette hypothèse trouve un appui dans le fait que la souche streptomcino-résistante contient beaucoup moins de fer (45%) que la souche sensible. L’hypothèse se trouve encore étayée par notre observation que la streptomycine, même à doses élevées, n’agit pas sur les deshydrogénases formique, lactique et succinique ni sur celles du glucose.
ABSTRACT: A l’aide du 32P nous avons suivi l’accumulation d’acides nucléiques chez les souches de Salmonella enteritidis et de Staphylococcus aureus, sensibles et résistantes à la streptomycine. Les souches résistantes accumulent à certaines périodes de leur prolifération plus de 32P que les souches sensibles. Elles sont plus riches en acides nucléiques, ainsi que nous l’avons contrôlé par les dosages chimiques des acides nucléiques. La quantité de 32P encorporé dans les acides nucléiques est d’environ 50% de la quantité totale de 32P fixé par les bactéries à la 24ème heure de leur prolifération.
ABSTRACT: Les souches streptomycino-résistantes de diverses espèces bactériennes sont, à certaines périodes de leur prolifération, beaucoup plus riches en acides ribonucléiques que les souches sensibles de même espèces. Les souches de Salmonella enteritidis résistant à la streptomycine sont, en outre, plus riches en acide désoxyribonucléique que les souches sensibles. La vitesse de prolifération des souches streptomycine-résistantes ne semble pas dépendre du taux d’acide ribonucléique. Les microgranules provenant d’une souche de Salmonella entertidis streptomycino-résistantes soun beaucoup plus riches en ARN et en ADN que les granules provenant de la souche sensible. La souche résistante est plus riche en fraction”libre” d’acide ribonucléique que la souche sensible. Les souches résistantes accumulent des quantités considérables d’ARN, tandis que leur teneur en protéines reste identique à celle des souches sensibles à la streptomycine.
ABSTRACT: Nous avons étudié le métabolisme des acides nucléiques d’une souche humaine avirulente de Mycobacterium tuberculosis sensible a 0,5 ug de streptomycine par millilitre et d’une souche résistant à 2000 ug d’antibiotique par millilitre en milieu de Dubos. Bien que les résultats obtenus par 3 différentes méthodes ne soient pas tout à fait superposables en valeur absolue, on a toujours trouvé, par chacune de ces méthodes, des différences quantitatives très nettes entre les taux des acides nucléiques des deux souches.
ABSTRACT: A la fin de la phase de latence et au début de la phase exponentielle de croissance, nous constatons une accumulation d’acide ribonucléique pour toutes les souches résistantes ou sensibles, mais cette accumulation est beaucoup plus grande chez les bactéries sensibles. Elle persiste pendant un temps plus ou moins long suivant l’espèce bactérienne.
ABSTRACT: I – La phase de latence de la souche azido-résistante est plus longue que celle de la souche sensible. Le rendement de la souche résistante est inférieur à celui de la souche sensible pendant les premières heures de la croissance, mais s’élève finalement à une même valeur. II – La souche azido-résistante accumule davantage d’acide ribonucléique que la souche sensible. Pour les autres constituants des bactéries nous n’avons pas trouvé de différence quantitative.
ABSTRACT: Tandis qu’une souche de Staphylococcus aureus streptomycino-résistante n’accumule que de l’acide ribonucléique, une souche de même espèce, mais pénicillino-résistante, accumule non seulement des quantités supérieures d’acide ribonucléique, mais également de protéines, de mononucléotides puriques et de composés phosphoriques acido-solubles. Ces différences sont peut-être basées sur les modes d’action différents des deux antibiotiques quant aux acides nucléiques : la pénicilline n’empêche pas la dépolymérisation de l’acide ribonucléique qui se dégrade et participe à la synthèse des protéines. La streptomycine, au contraire, se complexifie avec l’acide ribonucléotique (ou avec les nucléoprotéines) et freine sa dépolymérisation.
ABSTRACT: La découverte des antibiotiques pose de nombreux problèmes d’ordre biochimique et biologique. Si l’on admet que chaque antibiotique agit spécifiquement sur un processus métabolique déterminé on peut, en effet, penser que la perte ou la transformation de ce processus métabolique entraine une résistance spécifique à l’antibiotique correspondant. Nous nous sommes proposé d’analyser le métabolisme des microbes résistants pour voir ce qui les différencie des microbes sensibles normaux de même espèce, puis de voir le comportement de cette souche vis-à-vis de certaines substances chimiques thérapeutiques différentes des antibiotiques. On sait que le fait d’être résistant à un antibiotique ne confère pas la résistance à un autre antibiotique. Cela laisse supposer que les processus de résistance aux divers antibiotiques ne sont pas identiques. Nous pourrions donc espérer déceler ces différences biochimiques entre les souches d’une même espèce, mais résistante chacune à un antibiotique différent.
ABSTRACT: Les bactéries servant pour ensemencer le milieu (eau poptonée et glucosée) ont été prélevées dans une culture en pleine phase exponentielle de croissance. La souche streptomycino-résistante utilisée a subi trois repiquages sur le milieu sans antibiotique pour éliminer toute trace éventuelle de streptomycine. Avec 7 mg de cocarboxylase pour 100 ml de milieu, des différences nettes apparaissent dans le métabolisme des acides nucléiques, suivant que la souche est résistante ou sensible.
ABSTRACT: La résistance aux antibiotiques s’accompagne toujours dans nos expériences d’une modification très nette de certains processus biochimiques et c’est avant tout le métabolisme des acides nucléiques qui est modifié, mais ce n’est pas pour toutes les substances antibiotiques, le même type d’acide nucléique qui est en cause.
ABSTRACT: La résistance aux antibiotiques s’accompagne toujours dans nos expériences d’une modification très nette de certains processus biochimiques et c’est avant tout le métabolisme des acides nucléiques qui est modifié, mais ce n’est pas pour toutes les substances antibiotiques, le même type d’acide nucléique qui est en cause.
ABSTRACT: L’activité antibiotique des dérivés du benzène paraît liée à la position des groupes nitrés et en rapport étroit avec leur mobilité. La combinaison formée dans la proportion de 4mol d’acide oléique pour une de streptomycine est beaucoup moins toxique que la streptomycine qu’elle contient et même que la dihydrostreptomycine et cependant son pouvoir bactériostatique in vitro ainsi que son action curative chez la Souris sont pratiquement égales à celles de la dihydrostreptomycine.
ABSTRACT: Divers travaux antérieurs ont montré que la pénicilline cause des perturbations dans le métabolisme ribonucléique chez les bactéries. Nous avons en effet constaté l’inhibition du catabolisme des ribomononucléotides puriques chez Clostridium sporogenes non-proliférant, ainsi qu’un ralentissement très sensible de la dégradation de l’acide ribonucléique au cours de l’autolyse. Nous avons proposé l’hypothèse suivante : l’inhibition du catabolysme des mononucléotides produit leur accumulation qui retentit sur d’autres étapes du catabolisme ribonicléique et en particulier sur la dépolymérisation des polynucléotides par la ribonucléase.
ABSTRACT: La péniciline inhibe le catabolisme bactérien de l’acide uridylique et plus encore celui de l’acide guanylique. Parmi les dérivés de ces mononucléotides, seuls les nucléosides ont leur catabolisme bloqué par l’antibiotique. L’action inhibitrice de la péniciline porte sur un système enzymatique que nous avons pu extraire des bactéries.
ABSTRACT: Pendant la phase latence qui précède la croissance logarithmique, une souche de Staphylocoque streptomycinoresistante accumule des quantités d’acide ribonucléique très supérieures a celle qui sont accumulées par la souche sensible dont dérive la résistante. L’acide désoxyribonucléique, les nucléotides et les protéines ne sont pas acculés en excès.
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