Subsystem: Control of cell elongation - division cycle in Bacilli
This subsystem's description is:
The characteristic shape of bacterial cells is mainly determined by the cell wall, the synthesis of which is orchestrated by penicillin-binding proteins (PBPs). Rod-shaped bacteria have two distinct modes of cell wall synthesis, involved in cell elongation and cell division, which are believed to employ different sets of PBPs. A long-held question has been how these different modes of growth are co-ordinated in space and time. Recently key players in the elongation-division cycle of Bacillus subtilis have been identified (Claessen et al., 2008): the cell division protein EzrA, and a newly discovered protein GpsB (for guiding PBP1 shuttling). Mutations in these genes have a synthetic phenotype with defects in both cell division and cell elongation. Furthermore, these phenotypes are tightly associated with disturbed localization of the major transglycosylase/transpeptidase of the cell, PBP1, which is involved in both elongation and division, dynamically relocates from the septum to the lateral wall during the cell cycle. EzrA and GpsB have partially differentiated roles in the localization cycle of PBP1, with EzrA mainly promoting the recruitment of PBP1 to division sites, and GpsB facilitating its removal from the cell pole, after the completion of pole maturation (Claessen et al., 2008)
References
Claessen D, Emmins R, Hamoen LW, Daniel RA, Errington J, Edwards DH. 2008. Control of the cell elongation-division cycle by shuttling of PBP1 protein in Bacillus subtilis. Mol Microbiol, 68(4):1029-46
Tavares JR, de Souza RF, Meira GL, Gueiros-Filho FJ. 2008. Cytological characterization of YpsB, a novel component of the Bacillus subtilis divisome. J Bacteriol, 190(21):7096-107
Cañas C, Carrasco B, Ayora S, Alonso JC. 2008. The RecU Holliday junction resolvase acts at early stages of homologous recombination. Nucleic Acids Res, 36(16):5242-9
McGregor N, Ayora S, Sedelnikova S, Carrasco B, Alonso JC, Thaw P, Rafferty J. 2005. The structure of Bacillus subtilis RecU Holliday junction resolvase and its role in substrate selection and sequence-specific cleavage. Structure, 13(9):1341-51.
For more information, please check out the description and the additional notes tabs, below
| Diagram | Functional Roles | Subsystem Spreadsheet | Description | Additional Notes | |||||||||
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The characteristic shape of bacterial cells is mainly determined by the cell wall, the synthesis of which is orchestrated by penicillin-binding proteins (PBPs). Rod-shaped bacteria have two distinct modes of cell wall synthesis, involved in cell elongation and cell division, which are believed to employ different sets of PBPs. A long-held question has been how these different modes of growth are co-ordinated in space and time. Recently key players in the elongation-division cycle of Bacillus subtilis have been identified (Claessen et al., 2008): the cell division protein EzrA, and a newly discovered protein GpsB (for guiding PBP1 shuttling). Mutations in these genes have a synthetic phenotype with defects in both cell division and cell elongation. Furthermore, these phenotypes are tightly associated with disturbed localization of the major transglycosylase/transpeptidase of the cell, PBP1, which is involved in both elongation and division, dynamically relocates from the septum to the lateral wall during the cell cycle. EzrA and GpsB have partially differentiated roles in the localization cycle of PBP1, with EzrA mainly promoting the recruitment of PBP1 to division sites, and GpsB facilitating its removal from the cell pole, after the completion of pole maturation (Claessen et al., 2008) References Claessen D, Emmins R, Hamoen LW, Daniel RA, Errington J, Edwards DH. 2008. Control of the cell elongation-division cycle by shuttling of PBP1 protein in Bacillus subtilis. Mol Microbiol, 68(4):1029-46 Tavares JR, de Souza RF, Meira GL, Gueiros-Filho FJ. 2008. Cytological characterization of YpsB, a novel component of the Bacillus subtilis divisome. J Bacteriol, 190(21):7096-107 Cañas C, Carrasco B, Ayora S, Alonso JC. 2008. The RecU Holliday junction resolvase acts at early stages of homologous recombination. Nucleic Acids Res, 36(16):5242-9 McGregor N, Ayora S, Sedelnikova S, Carrasco B, Alonso JC, Thaw P, Rafferty J. 2005. The structure of Bacillus subtilis RecU Holliday junction resolvase and its role in substrate selection and sequence-specific cleavage. Structure, 13(9):1341-51. Notably, GpsB is tightly clustered with PBP1 in the majority of microorganisms where it occurs (in class Bacilli only), while EzrA is located in a separate locus. This clustering of a group of proteins with the Penicillin-binding protein 1 (PBP1) – was what trigger the encoding of this Subsystem (SS), originally created by Ross Overbeek as a clustering-based SS: “CBSS-1307.2.peg.138”. Remarkably, the PBP1//GpsB gene cluster also includes a number of proteins involved in chromosomal replication – Recombination protein RecU (required for proper segregation), Endonuclease III, Chromosome replication initiation protein DnaD (believed to be associated with primosome). This functional association might point to a mechanism of coordination between chromosomal replication and the newly elucidated mechanism (PBP1/GspB/ErzA) of switching between the two modes of growth - cell elongation and cell division in Bacilli. A number of hypothetical proteins are associated with this cluster as well. An interesting group of several related protein families (Hyp1, Hyp2, Hyp3), located immediately downstream of PBP1, all share homology within their C-termini, but differ wildly in the N-termini. | |||||||||||||
