title: Adaptive response to simple alkylating agents in the phototrophic bacteria Rhodobacter capsulatus and R.sphaeroides.
abstract: The presence of an adaptive response to low doses of alkylating chemicals in the phototrophic bacteria Rhodobacter sphaeroides and R.capsulatus has been studied. Results obtained show that both strains display this repair response against the challenge doses of N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), when they are pretreated with low doses of this compound for 120 min. The adaptive response of both R.sphaeroides and R.capsulatus induced an increase of cell survival and a decrease of mutagenesis in the MNNG-pretreated cells. Furthermore, the MNNG-induced adaptive repair also gives protection to diethylsulphate and ethylmethanesulphonate in both phototrophic bacteria. Finally, the MNNG-promoted adaptive response is sensitive to inhibitors of protein synthesis such as chloramphenicol, indicating that this DNA repair mechanism needs protein synthesis in R.sphaeroides and R.capsulatus, in a way similar to that which occurs in Escherichia coli.
authors.affiliation: Department of Genetics and Microbiology, Autonomous University of Barcelona, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Vericat
authors.forename: J
authors.initials: J
authors.lastname: Barbé
mesh_terms: D002701:Chloramphenicol / Q000494:pharmacology; D008769:Methylnitronitrosoguanidine / Q000494:pharmacology*; D009153:Mutagens; D012242:Rhodobacter sphaeroides / Q000187:drug effects* / Q000254:growth & development; D012241:Rhodopseudomonas / Q000187:drug effects* / Q000254:growth & development; D013045:Species Specificity
chemical_list: D009153:Mutagens; D008769:Methylnitronitrosoguanidine; D002701:Chloramphenicol