title: Identification of genes affecting expression of phosphoglycerate kinase on the surface of group B streptococcus.
abstract: Group B streptococcal phosphoglycerate kinase (GBS-PGK), a glycolytic enzyme, has previously been identified on the surface of group B streptococcus (GBS). To identify genes involved in surface expression of GBS-PGK, we performed Tn917 mutagenesis followed by quantification of PGK expressed on the GBS surface. Tn917 mutagenesis identified 4 genes (sag0966, sag0979, sag0980, and sag1003) that when disrupted, alter expression of GBS-PGK on the bacterial surface. Three of the identified genes were localized to a region of the GBS genome containing genes (sag0973-sag0977) predicted to be involved in resistance to antimicrobial peptides. One mutant isolate, designated NCS13sag1003::Tn917, was found to have increased sensitivity to the antimicrobial peptides bacitracin and nisin. In addition, all of the mutant strains assayed were found to have decreased β-hemolysis. In conclusion, we have identified genes involved in surface expression of GBS-PGK. These genes also appear to be involved in antimicrobial peptide resistance and regulate expression of the β-hemolysin.
authors.affiliation: Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, Canada. tboone@ualberta.ca
authors.forename: Tyler J
authors.initials: TJ
authors.lastname: Boone
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Tyrrell
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000942:Antigens, Bacterial / Q000235:genetics / Q000378:metabolism; D001414:Bacitracin / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology; D005798:Genes, Bacterial; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D009561:Nisin / Q000494:pharmacology; D010455:Peptides / Q000235:genetics / Q000378:metabolism; D010735:Phosphoglycerate Kinase / Q000235:genetics* / Q000378:metabolism; D013292:Streptococcus agalactiae / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D006460:Hemolysin Proteins; D008565:Membrane Proteins; D010455:Peptides; C070010:streptococcal beta antigen; D001414:Bacitracin; D009561:Nisin; D010735:Phosphoglycerate Kinase