Growth and division of Streptococcus pneumoniae: localization of the high molecular weight penicillin-binding proteins during the cell cycle
Article first published online: 30 SEP 2003
Volume 50, Issue 3, pages 845–855, November 2003
How to Cite
Morlot, C., Zapun, A., Dideberg, O. and Vernet, T. (2003), Growth and division of Streptococcus pneumoniae: localization of the high molecular weight penicillin-binding proteins during the cell cycle. Molecular Microbiology, 50: 845–855. doi: 10.1046/j.1365-2958.2003.03767.x
- Issue published online: 6 OCT 2003
- Article first published online: 30 SEP 2003
- Accepted 8 August, 2003.
The bacterial peptidoglycan, the main component of the cell wall, is synthesized by the penicillin-binding proteins (PBPs). We used immunofluorescence microscopy to determine the cellular localization of all the high molecular weight PBPs of the human pathogen Streptococcus pneumoniae, for a wild type and for several PBP-deficient strains. Progression through the cell cycle was investigated by the simultaneous labelling of DNA and the FtsZ protein. Our main findings are: (i) the temporal dissociation of cell wall synthesis, inferred by the localization of PBP2x and PBP1a, from the constriction of the FtsZ-ring; (ii) the localization of PBP2b and PBP2a at duplicated equatorial sites indicating the existence of peripheral peptidoglycan synthesis, which implies a similarity between the mechanism of cell division in bacilli and streptococci; (iii) the abnormal localization of some class A PBPs in PBP-defective mutants which may explain the apparent redundancy of these proteins in S. pneumoniae.