Regulation of the pts operon in low G+C Gram-positive bacteria.
The sugar transport system called phosphoenolpyruvate: sugar phosphotransferase (PTS) is widespread among eubacteria. Its is generally composed of two cytoplasmic proteins, HPr and El, which are found in all bacteria possessing a PTS, and a family of Ells whose number, specificity, and molecular structure in terms of domain arrangement vary from species to species. In low G+C Gram-positive bacteria, the genes coding for the general proteins HPr and El, designated ptsH and ptsl respectively, are organized into the pts operon. In this paper, we summarize current knowledge about the regulation of the pts operon in low G+C Gram-positive bacteria. Physiological data indicate that El and most particularly HPr make up a substantial proportion of cellular proteins. Their synthesis is not coordinated and is influenced by environmental factors. The principal DNA cis-elements involved in the regulation of pts operon transcription are a strong promoter whose sequence and structure are very similar to those of the canonical promoter recognized by the Escherichia coli and Bacillus subtilis major RNA polymerases, a 5'-untranslated region, a rho-dependent terminator located at the 5' end of ptsl, and an intrinsic terminator located downstream from ptsl. Analysis of ptsH and ptsl Shine-Dalgarno sequences as well as experimental results obtained with a Streptococcus salivarius mutant suggest that the expression of HPr and El is also controlled at the translation level.
Vadeboncoeur
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Département de Biochimie et de Microbiologie, Faculté des Sciences et de Génie, Université Laval, Sainte-Foy, Québec, Canada. Christian.Vadeboncoeur@bcm.ulaval.ca
Frenette
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Lortie
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D000818:Animals; D001483:Base Sequence; D015964:Gene Expression Regulation, Bacterial; D015971:Gene Expression Regulation, Enzymologic; D006094:Gram-Positive Bacteria / Q000201:enzymology* / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D009876:Operon; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics*; D011401:Promoter Regions, Genetic; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid
D010731:Phosphoenolpyruvate Sugar Phosphotransferase System