Studies of the binding of actinomycin and related compounds to DNA

Variation of the supercoils in closed circular DNA by binding of antibiotics and drugs: evidence for molecular models involving intercalation.

15 The absence of a preheating effect in PRi is to be contrasted with the marked preheating effect observed by Horiuchi et al., J. Mol. Biol., 3, 703 (1961), in a mutant showing thermolabile repression of f-galactosidase synthesis. 16 Garen, A., and H. Echols, these PROCEEDINGS, 48, 1398 (1962). 17 Gallant, J., and R. Stapleton, Bacteriol. Proc., p. 124 (1963). 18 Gallant, J., and R. Stapleton, manuscript in preparation. 19 By \"temperature-sensitive,\" we mean responding differently to temperature than growth rate. The use of the differential plot automatically normalizes to the growth rate.

A molecular mechanism of mitomycin action: linking of complementary dna strands.

Publisher Summary The chapter discusses the current understanding of actinomycin action at the molecular level. This discussion is related particularly to a model recently proposed for the reaction of actinomycin with DNA and to the implications of this model for the template function of helical nucleic acids. Actinomycin blocks the expression of genetic potentialities in several ways. The most prominent of these involves suppression of the formation of the primary cellular gene products; the ribonucleic acids (RNAs). The antibiotic also affects gene action, by preventing the transport of gene products, from nucleus to cytoplasm. In some mammalian cells, exposure to actinomycin is associated with the breakdown of previously synthesized RNA and this may constitute a third form of interference, with the gene action, although such depolymerization of RNA may merely reflect the existence of a normal turnover cycle. The actinomycin has also been applied to the analysis of gene action and the role of RNA metabolism in many systems. The chapter also reviews briefly some of these areas. It has not been attempted to include all the relevant contributions, but was tried to cite representative studies that illustrate the nature of actinomycin action, within a particular experimental framework, or exemplify some current applications of the antibiotic to various biological problems and the kind of information it can help to obtain.

Actinomycin and Nucleic Acid Function

On physico-chemical interactions between daunomycin and nucleic acids.

ACTINOMYCIN is well known to possess cytostatic properties in mammalian tissues1. Foley et al.
2 have shown the inhibitory effect of actinomycin on the cell-growth of 12 microbiological systems under various experimental conditions. In our work on the mode of action of actinomycin, Neurospora crassa was used as test organism.

Action of Nucleic Acids on the Inhibition of Growth by Actinomycin of Neurospora crassa

On the mode of action of actinomycins

IT has been shown1,2 that treatment of growing cells of E. coli B (strain 9637 from A.T.C.C.) with mitomycin C (MC) results in inhibition of deoxyribonucleic acid (DNA) formation. The synthesis of ribonucleic acid (RNA) and protein was unaffected at low levels of MC. The addition of MC in higher concentrations also blocks the synthesis of RNA and protein.

H. M. Rauen

Papers

Action of Nucleic Acids on the Inhibition of Growth by Actinomycin of Neurospora crassa

On the mode of action of actinomycins

Degradation of deoxyribonucleic acid in Escherichia coli cells treated with mitomycin C.