ABSTRACT
Four strains belonging to the genus Bacillus, capable of degrading polychlorinated biphenyls (PCB), were isolated by screening the collection strains of soil bacteria, degrading a organochlorine pesticide, hexachlorocyclohexane (HCCH). A method for production of tritium-labeled PCB was developed. Consumption and degradation of PCB by the soil bacterial strains selected were studied using tritium-labeled PCB and GLC. It was demonstrated that PCB are degradable both in culture media and under in model soil samples.
Subject(s)
Bacillus/metabolism , Polychlorinated Biphenyls/metabolism , Biodegradation, Environmental , Chromatography, GasABSTRACT
Study of the lethal effect of NMU on radiosensitive strains rad2, rad54 and xrs2 of Saccharomyces cerevisiae has demonstrated that the mutations rad2 and rad54 increase the sensitivity of these strains to low doses of the mutagen. Mutations rad2, rad54 and xrs2 decreases the mutagenic effect of NMU. The study of nature of mutations induced by NMU in ade2 locus has shown that they are mainly the base substitutions. Mutations of radiosensitivity do not influence the nature of NMU-induced mutations in ade2 locus.
Subject(s)
Methylnitrosourea/pharmacology , Mutagens/pharmacology , Nitrosourea Compounds/pharmacology , Radiation Tolerance , Saccharomyces cerevisiae/genetics , DNA Repair , Mutation , Saccharomyces cerevisiae/drug effectsABSTRACT
Effect of mutations rad2 and rad54 in homozygous state on survival, mitotic segregation and crossing-over induced by NMU in yeast was studied. Mutation rad2 did not influence on these effects of NMU. The mutation rad54 increased sensitivity to the lethal effect, the frequencies of NMU-induced segregation and crossing-over were decreased in the strain rad54 rad54. The recombinogenic effect of NMU on yeast was lower than under the action of UV and gamma rays.
