Regulation of the Bacillus subtilis GlcT antiterminator protein by components of the phosphotransferase system.
Bacillus subtilis utilizes glucose as the preferred source of carbon and energy. The sugar is transported into the cell by a specific permease of the phosphoenolpyruvate:sugar phosphotransferase system (PTS) encoded by the ptsGHI operon. Expression of this operon is induced by glucose and requires the action of a positive transcription factor, the GlcT antiterminator protein. Glucose availability is sensed by glucose-specific enzyme II (EIIGlc), the product of ptsG. In the absence of inducer, the glucose permease negatively controls the activity of the antiterminator. The GlcT antiterminator has a modular structure. The isolated N-terminal part contains the RNA-binding protein and acts as a constitutively acting antiterminator. GlcT contains two PTS regulation domains (PRDs) at the C terminus. One (PRD-I) is the target of negative control exerted by EIIGlc. A conserved His residue (His-104 in GlcT) is involved in inactivation of GlcT in the absence of glucose. It was previously proposed that PRD-containing transcriptional antiterminators are phosphorylated and concomitantly inactivated in the absence of the substrate by their corresponding PTS permeases. The results obtained with B. subtilis glucose permease with site-specific mutations suggest, however, that the permease might modulate the phosphorylation reaction without being the phosphate donor.
Lehrstuhl für Mikrobiologie, Institut für Mikrobiologie, Biochemie und Genetik der Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91058 Erlangen, Germany.
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Bachem
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Stülke
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics*; D001426:Bacterial Proteins; D001665:Binding Sites; D001692:Biological Transport; D017124:Conserved Sequence; D004790:Enzyme Induction; D015964:Gene Expression Regulation, Bacterial; D005947:Glucose / Q000378:metabolism*; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009876:Operon; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D016601:RNA-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000096:biosynthesis* / Q000235:genetics
D001426:Bacterial Proteins; C115000:GlcT protein, Bacillus subtilis; D016601:RNA-Binding Proteins; D014157:Transcription Factors; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C031629:phosphoenolpyruvate-glucose phosphotransferase; D005947:Glucose