Role of penicillin-binding protein PBP 2B in assembly and functioning of the division machinery of Bacillus subtilis.
We have characterized the role of the penicillin-binding protein PBP 2B in cell division of Bacillus subtilis. We have shown that depletion of the protein results in an arrest in division, but that this arrest is slow, probably because the protein is relatively stable. PBP 2B-depleted filaments contained, at about their mid-points, structures resembling partially formed septa, into which most, if not all, of the division proteins had assembled. Although clearly deficient in wall material, membrane invagination seemed to continue, indicating that membrane and wall ingrowth can be uncoupled. At other potential division sites along the filaments, no visible ingrowths were observed, although FtsZ rings assembled at regular intervals. Thus, PBP 2B is apparently required for both the initiation of division and continued septal ingrowth. Immunofluorescence microscopy showed that the protein is recruited to the division site. The pattern of localization suggested that this recruitment occurs continually during septal ingrowth. During sporulation, PBP 2B was present transiently in the asymmetrical septum of sporulating cells, and its availability may play a role in the regulation of sporulation septation.
Daniel
R A
RA
Sir William Dunn School of Pathology, University of Oxford, Oxford OX1 3RE, UK.
Harry
E J
EJ
Errington
J
J
D001412:Bacillus subtilis / Q000166:cytology / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D002352:Carrier Proteins / Q000235:genetics* / Q000378:metabolism*; D002453:Cell Cycle; D002455:Cell Division; D003598:Cytoskeletal Proteins; D017353:Gene Deletion; D015964:Gene Expression Regulation, Bacterial; D006602:Hexosyltransferases; D015151:Immunoblotting; D008854:Microscopy, Electron; D002267:Muramoylpentapeptide Carboxypeptidase / Q000235:genetics* / Q000378:metabolism*; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D013171:Spores, Bacterial / Q000502:physiology
D001426:Bacterial Proteins; D002352:Carrier Proteins; D003598:Cytoskeletal Proteins; C071525:FtsZ protein, Bacteria; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase