天然和突变微生物核糖核酸酶的SOS诱导能力。

SOS-inducing ability of native and mutant microbial ribonucleases.

作者信息

Ilinskaya O N, Karamova N S, Ivanchenko O B, Kipenskaya L V

机构信息

GENTOX Laboratory, Microbiology Department, Kazan State University, Tatarstan, Russia.

出版信息

Mutat Res. 1996 Jul 22;354(2):203-9. doi: 10.1016/0027-5107(96)00012-7.

DOI:10.1016/0027-5107(96)00012-7

PMID:8764949

Abstract

The results of genotoxicity testing of microbial ribonucleases from Bacillus species with different catalytic activity obtained by site-directed mutagenesis in SOS chromotest are reported. At the concentrations 0.1-1 mg/ml, the induction factor for wild-type bacillar binase, barnase and mutant Arg58Lys binase with 100% activity was found to be significantly higher than 1.5 (1.8-2.8). Mutant RNases having decreased catalytic activity (binases with replacements Lys26Ala, Arg61Gln, His101Glu) or through natural inhibitor barstar inactivated wild-type RNase exhibited no SOS-inducing potency. The ability of native bacillar RNases and mutant enzymes possessing high catalytic activity comparable with the activity of wild-type RNase to cause the SOS response indicates that genotoxicity is mediated through the probable cleavage of cellular RNA.

摘要

报道了通过定点诱变获得的具有不同催化活性的芽孢杆菌属微生物核糖核酸酶在SOS色变试验中的遗传毒性测试结果。在浓度为0.1 - 1mg/ml时，发现野生型芽孢杆菌核糖核酸酶、芽孢杆菌核酸酶和活性为100%的突变型精氨酸58赖氨酸核糖核酸酶的诱导因子显著高于1.5（1.8 - 2.8）。催化活性降低的突变型核糖核酸酶（赖氨酸26丙氨酸、精氨酸61谷氨酰胺、组氨酸101谷氨酸替代的核糖核酸酶）或通过天然抑制剂芽孢杆菌抗酶失活的野生型核糖核酸酶均未表现出SOS诱导能力。天然芽孢杆菌核糖核酸酶和具有与野生型核糖核酸酶活性相当的高催化活性的突变酶引起SOS反应的能力表明，遗传毒性是通过细胞RNA的可能切割介导的。