[Quasi-adaptive response to alkylating agents in Escherichia coli and Ada-protein functions].
In 2005 we have described in exponentially growing E. coli cells a new fundamental genetic phenomenon,--quasi-adaptive response to alkylating compounds (quasi-Ada). Phenotypic expression of quasi-Ada is similar to the true Ada response. However, in contrast to the letter, it develops in the course of pretreatment of the cells by a sublethal dose of nonalkylating agent, an NO-containing dinitrosyl iron complex with glutathione (DNICglu). To reveal the mechanisms of quasi-adaptation and its association with the function of the Ada regulatory protein, here we used a unique property of dual gene expression regulation of aidB1 gene, a part of the Ada-regulon, namely its relative independence from Ada protein in anaerobic conditions. Based on the results of aidB1 gene expression analysis an EPR spectra of E. coli MV2176 cells (aidB1::lacZ) in aerobic and anaerobic conditions after the corresponding treatments, we conclude that the function and the spatial structure of meAda and [(Cys-)2Fe+(NO+)2]Ada are identical and thus the nitrosylated protein represents a regulator of the Ada regulon gene expression during quasi-adaptation development.
Vasil'eva
S V
SV
Moshkovskaia
E Iu
EIu
Terekhov
A S
AS
Mikoian
V D
VD
Vanin
A F
AF
D000220:Adaptation, Biological / Q000187:drug effects* / Q000502:physiology; D000477:Alkylating Agents / Q000494:pharmacology*; D004926:Escherichia coli / Q000235:genetics / Q000254:growth & development*; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects* / Q000502:physiology; D005978:Glutathione / Q000494:pharmacology; D058085:Iron Compounds / Q000494:pharmacology; D009603:Nitroso Compounds / Q000494:pharmacology; D019853:O(6)-Methylguanine-DNA Methyltransferase / Q000235:genetics / Q000378:metabolism*; D018085:Regulon / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
C090096:AidB protein, E coli; D000477:Alkylating Agents; D029968:Escherichia coli Proteins; D058085:Iron Compounds; D009603:Nitroso Compounds; D014157:Transcription Factors; C045675:Ada protein, E coli; D019853:O(6)-Methylguanine-DNA Methyltransferase; D005978:Glutathione