Cell wall synthesis
People
The peptidoglycan cell wall is one of the defining features of bacteria. It covers the surface of the cell and confers protection to mechanical damage. It also secures cell integrity in the light of the large turgor pressure pushing outwards on the cytoplasmic membrane that underlies the wall. The wall defines the shape of the cell, and must be continually enlarged to accommodate cell growth. It also plays a key role in cell division, during which the wall must invaginate to form the new poles of the daughter cells.
Peptidoglycan was probably present in the last common ancestor of the bacteria and thus, in some of the first true cells on earth. The wall is the target for our best antibiotics, such as penicillins, cephalosprins and vancomycin, and fragments of the wall trigger critical responses by our innate immune systems. Despite this profound importance there are still surprisingly large gaps in our understanding of the fundamental mechanisms of cell wall synthesis. Although the gross structure of peptidoglycan is known – long glycan strands with short peptide cross bridges, how it is shaped into a huge single molecule or “sacculus” covering the surface of the cell remains to be worked out.
This lab discovered that the actin like MreB proteins form elongated helical filaments just under the cell surface, and which are required for cell shape. We have identified a number of cell wall associated factors that interact with MreB. We are interested in understanding how the MreB system controls cell wall synthesis in order to bring about cell shape determination.
Key papers from the lab
Jones LJF, Carballido-López R and Errington J. (2001) Control of cell shape in bacteria: helical, actin-like filaments in Bacillus subtilis. Cell 104, 913-922.
Daniel RA and Errington J. (2003) Control of cell morphogenesis in bacteria: two distinct ways to make a rod-shaped cell. Cell 113, 767-776.
Carballido-López R, Formstone A, Li Y, Ehrlich SD, Noirot P and Errington J. (2006) Actin homolog MreBH governs cell morphogenesis by localization of the cell wall hydrolase LytE. Developmental Cell 11, 399-409.
Kawai Y, Daniel RA, Errington J (2009) Regulation of cell wall morphogenesis in Bacillus subtilis by recruitment of PBP1 to the MreB helix. Mol. Microbiol 71, 1131-1144.
Schirner K, Marles-Wright J, Lewis RJ, Errington J. (2009) Distinct and essential morphogenic functions for wall- and lipo-teichoic acids in Bacillus subtilis. EMBO J 28, 830-842.
Kawai Y, Marles-Wright J, Cleverley RM, Emmins R, Ishikawa S, Kuwano M, Heinz N, Bui NK, Hoyland CN, Ogasawara N, Lewis RL, Vollmer W, Daniel RA, Errington J. (2011) A widespread family of bacterial cell wall assembly proteins. EMBO J 30, 4931-4941.
Kawai Y, Mercier R, Errington J. (2014) Bacterial cell morphogenesis does not require a preexisting template structure. Curr Biol. 24, 863-867.
