[Gene yddG of Escherichia coli encoding the putative exporter of aromatic amino acids: constitutive transcription and dependence of the expression level on the cell growth rate].
Gene yddG of Escherichia coli encodes a protein of the inner membrane. Data obtained earlier demonstrated that under conditions of oversynthesis of aromatic amino acids, YddG promotes their export from E. coli cells. In this work, a method of primer extension was used to localize the P(yddG) promoter, which corresponds to E. coli promoters recognized by RNA polymerase in complex with sigma70 or sigma(S) subunits. By constructing a gene of the hybrid protein YddG'-LacZ at the intrinsic site of gene yddG location in the E. coli chromosome and analyzing the activity of beta-galactosidase in cells growing on laboratory media LB and M9, the constitutive type of yddG expression at a low level was demonstrated (the activity reached approximately 3 to 4% of the level of LacZ in E. coli wild-type cells under induction of the lac operon). The expression of yddG had a twofold increase under conditions of retarded cell growth upon the stress caused by the high NaCl content (0.6 M) or by the presence of phenylalanine excess quantities (> 1 mM) in the culture medium.
Tsyrenzhapova
I S
IS
Doroshenko
V G
VG
Aĭrikh
L G
LG
Mironov
A S
AS
Mashko
S V
SV
D024322:Amino Acids, Aromatic / Q000378:metabolism*; D001483:Base Sequence; D001692:Biological Transport; D004926:Escherichia coli / Q000166:cytology / Q000254:growth & development / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000502:physiology*; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D018272:Porins / Q000235:genetics / Q000502:physiology*; D011401:Promoter Regions, Genetic; D001616:beta-Galactosidase / Q000378:metabolism
D024322:Amino Acids, Aromatic; D029968:Escherichia coli Proteins; D018272:Porins; D001616:beta-Galactosidase