Mechanisms of the radioprotective effect of cysteamine in Escherichia coli
The values of the oxygen effect (m) and the maximal protective effect of cysteamine (DMF*) were estimated for four Escherichia coli strains: AB1157 (wild type), AB1886 (uvrA), AB2463 (recA), and p3478 (polA). A correlation made between DMF* and m as well as the kinetics of the increase of DMF with oxygen depletion showed that the protective effect of cysteamine is realized by three mechanisms: (i) anoxia achieved by oxygen reduction, with the DMF varying from 2.2 to 4.2 for different E. coli strains (this protection is the major contribution to the entire mechanism); (ii) lowering of the indirect radiation effect; i.e., for 50 mM cysteamine DMF does not exceed 1.1; and (iii) increase of the efficiency of enzymatic repair. The latter effect of cysteamine is registered only with the wild-type E. coli, the DMF being not less than 1.4.
- Research Organization:
- Institute of Biological Physics, Moscow (USSR)
- OSTI ID:
- 6856593
- Journal Information:
- Radiat. Res.; (United States), Journal Name: Radiat. Res.; (United States) Vol. 114:3; ISSN RAREA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANOXIA
BACTERIA
BIOLOGICAL VARIABILITY
DRUGS
ELEMENTS
ESCHERICHIA COLI
GENETIC VARIABILITY
MICROORGANISMS
NONMETALS
OXYGEN
RADIOPROTECTIVE SUBSTANCES
RADIOSENSITIVITY EFFECTS
SURVIVAL CURVES