Cloning, nucleotide sequence, and regulation of the Bacillus subtilis pbpE operon, which codes for penicillin-binding protein 4* and an apparent amino acid racemase.
Penicillin-binding protein 4* (PBP 4*) was purified from Bacillus subtilis, its N-terminal sequence was determined, and the coding gene, termed pbpE, was cloned and sequenced. The predicted amino acid sequence of PBP 4* exhibited similarity to those of other penicillin-recognizing enzymes. Downstream of pbpE there was a second gene, termed orf2, which exhibited sequence similarity with aspartate racemase. The two genes were found to constitute an operon adjacent to and divergently transcribed from the sacB gene at 296 degrees on the chromosomal map. A weak beta-lactamase activity was associated with PBP 4*, but no enzymatic activity was found for the product of orf2. Mutation of pbpE, orf2, or both genes resulted in no observable effect on growth, sporulation, spore heat resistance, or spore germination. A translational pbpE-lacZ fusion was weakly expressed during vegetative growth and was significantly induced at the onset of sporulation. This induction depended on the activity of the spo0A product in relieving repression by the abrB repressor. A single transcription start site which was apparently dependent on E sigma A was detected upstream of pbpE.
Department of Biochemistry, University of Connecticut Health Center, Farmington 06032.
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D000591:Amino Acid Isomerases / Q000235:genetics*; D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics*; D001426:Bacterial Proteins; D001483:Base Sequence; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D006602:Hexosyltransferases; D008969:Molecular Sequence Data; D002267:Muramoylpentapeptide Carboxypeptidase / Q000096:biosynthesis / Q000235:genetics* / Q000302:isolation & purification; D016296:Mutagenesis; D009876:Operon / Q000235:genetics*; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D017421:Sequence Analysis; D017384:Sequence Deletion; D017386:Sequence Homology, Amino Acid; D013171:Spores, Bacterial / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics; D014158:Transcription, Genetic; D001618:beta-Lactamases / Q000096:biosynthesis
C060762:AbrB protein, Bacillus subtilis; D001426:Bacterial Proteins; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D046915:Penicillin-Binding Proteins; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase; D001618:beta-Lactamases; D000591:Amino Acid Isomerases; C019749:aspartate racemase