Functional redundancy of division specific penicillin‐binding proteins in Bacillus subtilis
نویسندگان
چکیده
Bacterial cell division involves the dynamic assembly of a diverse set of proteins that coordinate the invagination of the cell membrane and synthesis of cell wall material to create the new cell poles of the separated daughter cells. Penicillin-binding protein PBP 2B is a key cell division protein in Bacillus subtilis proposed to have a specific catalytic role in septal wall synthesis. Unexpectedly, we find that a catalytically inactive mutant of PBP 2B supports cell division, but in this background the normally dispensable PBP 3 becomes essential. Phenotypic analysis of pbpC mutants (encoding PBP 3) shows that PBP 2B has a crucial structural role in assembly of the division complex, independent of catalysis, and that its biochemical activity in septum formation can be provided by PBP 3. Bioinformatic analysis revealed a close sequence relationship between PBP 3 and Staphylococcus aureus PBP 2A, which is responsible for methicillin resistance. These findings suggest that mechanisms for rescuing cell division when the biochemical activity of PBP 2B is perturbed evolved prior to the clinical use of β-lactams.
منابع مشابه
PBP1 is a component of the Bacillus subtilis cell division machinery.
Bacillus subtilis penicillin-binding protein PBP1 has been implicated in cell division. We show here that a PBP1 knockout strain is affected in the formation of the asymmetric sporulation septum and that green fluorescent protein-PBP1 localizes to the sporulation septum. Localization of PBP1 to the vegetative septum is dependent on various cell division proteins. This study proves that PBP1 for...
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