Growth and division of Streptococcus pneumoniae: localization of the high molecular weight penicillin-binding proteins during the cell cycle

Mol Microbiol. 2003 Nov;50(3):845-55. doi: 10.1046/j.1365-2958.2003.03767.x.


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.

MeSH terms

  • Aminoacyltransferases*
  • Bacterial Proteins / chemistry
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Base Sequence
  • Carrier Proteins / chemistry
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Division / physiology
  • Cell Polarity
  • Cytoskeletal Proteins / genetics
  • Cytoskeletal Proteins / metabolism
  • Fluorescent Antibody Technique
  • Hexosyltransferases / chemistry
  • Hexosyltransferases / genetics
  • Hexosyltransferases / metabolism*
  • Molecular Sequence Data
  • Molecular Weight
  • Muramoylpentapeptide Carboxypeptidase / chemistry
  • Muramoylpentapeptide Carboxypeptidase / genetics
  • Muramoylpentapeptide Carboxypeptidase / metabolism*
  • Mutation
  • Penicillin-Binding Proteins
  • Peptide Synthases*
  • Peptidoglycan / metabolism
  • Peptidyl Transferases / chemistry
  • Peptidyl Transferases / genetics
  • Peptidyl Transferases / metabolism*
  • Protein Transport
  • Streptococcus pneumoniae / growth & development
  • Streptococcus pneumoniae / metabolism*


  • Bacterial Proteins
  • Carrier Proteins
  • Cytoskeletal Proteins
  • FtsZ protein, Bacteria
  • Penicillin-Binding Proteins
  • Peptidoglycan
  • penicillin-binding protein 2a, Streptococcus
  • Aminoacyltransferases
  • penicillin-binding protein 2b, Streptococcus
  • Peptidyl Transferases
  • Hexosyltransferases
  • Muramoylpentapeptide Carboxypeptidase
  • Peptide Synthases