ABSTRACT
The stimulating effect of DNAase 1 on Escherichia coli reproduction has been studied depending on the content of slowly growing cells in the inoculation culture in the phase of delayed growth. Three cell fractions of E. coli have been obtained using the stepwise separation of the population in terms of buoyant density in the phase of delayed growth. In contrast to fractions I and II the fraction III contains cells with delayed growth, permeable to exogenous DNAase 1 and sensitive to the action of this enzyme. The faster growth of bacterial cells has been shown to be caused by the direct ferment action on the slowly growing cells. The autometabolites and autolysates don't take part in this process.
Subject(s)
Bacillus subtilis/drug effects , Deoxyribonuclease I/pharmacology , Escherichia coli/drug effects , Bacillus subtilis/growth & development , Bacillus subtilis/metabolism , Cell Division/drug effects , Culture Media , DNA, Bacterial/biosynthesis , DNA, Bacterial/drug effects , Escherichia coli/growth & development , Escherichia coli/metabolism , Stimulation, ChemicalABSTRACT
Cytotoxicity of RNAase from Bacillus intermedius was studied in vitro and in vivo. It was shown that the enzyme had slightly pronounced cytotoxicity according to the tests with inhibition of cell proliferation and biosynthesis of cell nucleic acids. The RNAase was also shown to impair the vital staining by neutral red. The efficiency of the impairment much more depended on the enzyme catalytic activity than on the proliferation and biosynthesis of nucleic acids. In vivo toxicity of RNAase from B. intermedius was 3-5 times higher than that of pancreatic RNAase. Possible mechanisms of the different toxicity of the enzymes are discussed.
Subject(s)
Bacillus/enzymology , Ribonuclease, Pancreatic/toxicity , Ribonucleases/toxicity , Amnion/pathology , Animals , Antineoplastic Agents , Cell Division/drug effects , Culture Media , Dose-Response Relationship, Drug , Female , Humans , In Vitro Techniques , Leukemia, Experimental/pathology , Leukemia, Lymphoid/pathology , Mice , Ovarian Neoplasms/pathology , Ribonuclease, Pancreatic/pharmacology , Ribonucleases/administration & dosage , Ribonucleases/pharmacologyABSTRACT
Identity of the mechanism of antitumour effectiveness of Bac. intermedius and pancreatic RNase and the enzyme independence of the catalytical activity are shown. Differential sensitivity of the implanted tumours of animals to RNase of Bac. intermedius is established.
