Structure and transcriptional regulation of the Escherichia coli adaptive response gene aidB.
Expression of the Escherichia coli aidB gene is induced in vivo by alkylation damage in an ada-dependent pathway and by anaerobiosis or by acetate at pH 6.5 in an ada-independent fashion. In this report, we present data on aidB gene structure, function, and regulation. The aidB gene encodes a protein of ca. 60 kDa that is homologous to several mammalian acyl coenzyme A dehydrogenases. Accordingly, crude extracts from an aidB-overexpressing strain showed isovaleryl coenzyme A dehydrogenase activity. aidB overexpression also reduced N-methyl-N'-nitro-N-nitrosoguanidine-induced mutagenesis. Both ada- and acetate/pH-dependent induction of aidB are regulated at the transcriptional level, and the same transcriptional start point is used for both kinds of induction. Ada protein plays a direct role in aidB regulation: methylated Ada is able to bind to the aidB promoter region and to activate transcription from aidB in an in vitro transcription-translation system using crude E. coli extracts.
Landini
P
P
Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, Worcester 01655.
Hajec
L I
LI
Volkert
M R
MR
D000222:Adaptation, Physiological / Q000235:genetics*; D000478:Alkylation; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004249:DNA Damage; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D044943:Fatty Acid Desaturases / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D050769:Isovaleryl-CoA Dehydrogenase; D008769:Methylnitronitrosoguanidine; D008969:Molecular Sequence Data; D016296:Mutagenesis; D019853:O(6)-Methylguanine-DNA Methyltransferase; D010088:Oxidoreductases / Q000378:metabolism; D044925:Oxidoreductases Acting on CH-CH Group Donors; D011401:Promoter Regions, Genetic / Q000235:genetics; D011485:Protein Binding; D011993:Recombinant Fusion Proteins; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors; D014158:Transcription, Genetic
C090096:AidB protein, E coli; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D008769:Methylnitronitrosoguanidine; D010088:Oxidoreductases; D044943:Fatty Acid Desaturases; D044925:Oxidoreductases Acting on CH-CH Group Donors; D050769:Isovaleryl-CoA Dehydrogenase; C045675:Ada protein, E coli; D019853:O(6)-Methylguanine-DNA Methyltransferase