Inhibition of the expression of penicillin resistance in Streptococcus pneumoniae by inactivation of cell wall muropeptide branching genes.

ABSTRACT: Penicillin-resistant strains of Streptococcus pneumoniae contain low affinity penicillin-binding proteins and often also produce abnormal indirectly crosslinked cell walls. However the relationship between cell wall abnormality and penicillin resistance has remained obscure. We now show that the genome of S. pneumoniae contains an operon composed of two genes (murM and murN) that encode enzymes involved with the biosynthesis of branched structured cell wall muropeptides. The sequences of murMN were compared in two strains: the penicillin-susceptible strain R36A producing the species-specific pneumococcal cell wall peptidoglycan in which branched stem peptides are rare, and the highly penicillin-resistant transformant strain Pen6, the cell wall of which is enriched for branched-structured s

SUBMITTER: Filipe SR 

PROVIDER: S-EPMC18328 | biostudies-literature | 2000 Apr

REPOSITORIES: biostudies-literature