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Biomedical subjects

F Arcamone

Publications and source records attributed to F Arcamone.

At least 91 records · Page 5Linked to original sources
PubMed1977

Specific interactions of distamycin A and its analogs with (A-T) rich and (G-C) rich duplex regions of DNA and deoxypolynucleotides.

The specific interaction of distamycin A and analogs with DNA's and synthetic deoxypolynucleotide duplexes were studied in detail by means of circular dichroism and the data were analyzed together with viscosity results of several natural DNA's. At low ligand to nucleotide ratio the previously reported specific binding to (A-T) pairs of DNA is verified by a highly favoured interaction with (A-T)-enriched segments of distamycins containing four and five methylpyrrole carboxamide units. At higher distamycin concentration a second specific binding to (G-C) pairs most probably through hydrogen bonding is established. Viscometric results suggest a distamycin-induced local bending of the helix and could support the idea of a preferential alignment of the ligand molecule along only one strand in the groove which differs from the netropsin interaction mechanism. The possibility of an overlapping binding of the oligopeptides in the small groove is discussed.

Animals↗
PubMed1977

Interaction of new derivatives of daunorubicin and adriamycin with DNA.

The interaction of a number of new derivatives of the antitumour antibiotics daunorubicin and adriamycin with calf-thymus DNA has been studied by equilibrium dialysis and low-shear viscosimetry. The results are interpreted in terms of structure of the compounds, also by examining molecular stereomodels.

Animals↗
PubMed1976

Synthesis and antitumor activity of 4-demethoxydaunorubicin, 4-demethoxy-7,9-diepidaunorubicin, and their beta anomers.

Four new derivatives of daunorubicin, characterized by the absence of the methoxyl group at the C-4 position, have been obtained by chemical synthesis. 4-Demethoxydaunorubicin (NSC-256439) was effective against L1210 and Gross leukemias and ascites and solid Sarcoma 180 at doses four to eight times lower than those effective for daunorubicin. The beta anomer of 4-demethoxydaunorubicin was active at doses 13and eight times higher than those of its corresponding alpha anomer against L1210 and Gross leukemias respectively. 4-Demethoxy-7,9-diepidaunorubicin and its beta anomer were devoid of any biologic activity at the doses tested.

Animals↗
PubMed1976

The effect of distamycin A on some biochemical functions of tissue cultures infected with Herpes simplex virus.

The antibiotic distamycin A displays no inhibition of protein synthesis in HeLa cell cultures. In HSV infected HeLa cell monolayers the drug exerts a partial inhibition of virus induced thymidine kinase synthesis but is devoid of inhibitory effect on the increase of activity of DNA polymerase and on total DNA synthesis. The antiviral activity of distamycin A is based on a mechanism which appears to be different from that displayed by other drugs such as actinomycin and IUD.

Culture Techniques↗
PubMed1975

Synthesis and antitumor properties of new glycosides of daunomycinone and adriamycinone.

The synthesis of 4'-epi-daunorubicin and of 4'-epi-adriamycin was performed by condensation of 2,3,6-trideoxy-3-trifluoroacetamido-4-O-trifluoroacetyl-alpha-L-arabino-hexopyranosyl chloride with daunomycinone or the protected adriamycinone derivative 17, respectively. Both the alpha and beta anomers were obtained and characterized. All new compounds are biologically active in cultured cells and the alpha anomers display noticeable activity in experimental tumors in mice. Interestingly, 4'-epi-adriamycin (4) appears nontoxic to cultured heart cells up to a concentration of 5 mug/ml.

Aminoglycosides↗
PubMed1975

DNA complexing antibiotics: daunomycin, adriamycin and their derivatives.

9-Acetyl-4-methoxy-7,8,9,11-tetrahydroxy-6,7,9,11-tetrahydroxy-o-(3'-amino-2',3',6'-trideoxy-alpha-L-lyxohexopyranoside) (daunomycin, daunorubicin, NSC-82 131, Daunoblasin), 14-hydroxy-daunorubicin (adriamycin, doxorubicin, NSC-123 127, Adriblastin), dihydrodaunomycin, their aglycones and other related compounds represent the group of S. peucetius derived antibiotics. The biosynthetic glycosides as well as some semisynthetic analogues or derivatives form strong complexes with double stranded DNA, which can be understood in terms of the known intercalation model. A clear relationship is found between the complex forming ability and the biological activity of the different compounds. The structure and configuration of the sugar moiety appear of primary importance for the stabilization of the complex and, therefore, for action. A class of side chain derivatives, namely adriamycin 14-0-esters, looks promising. Different tissue distribution of such derivatives may result in new useful anticancer drugs.

Animals↗
PubMed1975

On the mechanism of inhibition of enzyme induction in Escherichia coli by distamycin A.

The mechanism of the interference of the antiviral antibiotic distamycin A with the bacterial cell has been investigated. Labelled distamycin A is firmly bound by E. coli cells and the binding process does not require metabolic energy as indicated by the use of inhibitors. The antibiotic does not induce gross alteration in the cell membrane but inhibits cyclic AMP accumulation in the cells exposed to a glucose-free medium. This inhibition is concomitant with that exerted on the synthesis of an inducible enzyme such as beta-galactosidase. By the method of pulse induction it appears that distamycin A exterts its inhibiting effect on inducible synthesis at the level of transcription. This effect is probably related to an interference with the positive control of enzyme synthesis performed via the system represented by cyclic AMP and the CRP protein.

Binding Sites↗