The Bacillus subtilis spoVD gene encodes a mother-cell-specific penicillin-binding protein required for spore morphogenesis.
The Bacillus subtilis spoVD gene has been cloned and sequenced. It encodes a 71,262 Da protein with extensive sequence similarity to penicillin-binding proteins from various organisms. The context of this gene in the B. subtilis chromosome, immediately upstream of the mur operon, suggests that it is related to the pbpB gene of Escherichia coli, which is involved in the synthesis of septal peptidoglycan during cell division. Expression of spoVD in E. coli leads to the synthesis of a membrane-associated protein of the size expected for SpoVD, which can bind labelled penicillin. However, insertional disruption of the spoVD gene has no effect on vegetative growth or division: a second pbp-like gene immediately upstream of spoVD is probably the functional homologue of E. coli pbpB. spoVD seems instead to have a specialized role in the morphogenesis of the spore cortex, which is a modified form of peptidoglycan. spoVD transcription appears to occur from a promoter recognized by the sigma E form of RNA polymerase. Analysis of the expression of a spoVD'-lacZ reporter gene supports this notion and indicates that a second level of negative regulation is dependent on the SpoIIID protein. SpoVD synthesis probably occurs only in the mother cell since both sigma E and SpoIIID are thought to be specific to this cell type. Such localization of SpoVD synthesis was supported by the results of a genetic test showing that expression of spoVD only in the mother cell is sufficient for spore formation. The results support the proposition that spore cortex formation is determined primarily by the mother cell.
Daniel
R A
RA
Sir William Dunn School of Pathology, University of Oxford, U.K.
Drake
S
S
Buchanan
C E
CE
Scholle
R
R
Errington
J
J
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D001483:Base Sequence; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics; D003001:Cloning, Molecular; D017931:DNA Primers; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D006602:Hexosyltransferases; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D009024:Morphogenesis; D002267:Muramoylpentapeptide Carboxypeptidase / Q000096:biosynthesis* / Q000235:genetics; D046915:Penicillin-Binding Proteins; D010406:Penicillins / Q000378:metabolism; D046928:Peptidoglycan Glycosyltransferase; D010458:Peptidyl Transferases; D016133:Polymerase Chain Reaction; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid; D013171:Spores, Bacterial / Q000502:physiology; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000378:metabolism
D001426:Bacterial Proteins; D002352:Carrier Proteins; D017931:DNA Primers; D029968:Escherichia coli Proteins; C478704:FtsI protein, E coli; D026901:Membrane Transport Proteins; D046915:Penicillin-Binding Proteins; D010406:Penicillins; C085450:SpoVD protein, Bacillus subtilis; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D046928:Peptidoglycan Glycosyltransferase; D001616:beta-Galactosidase; D002267:Muramoylpentapeptide Carboxypeptidase