Profiling of β-lactam selectivity for penicillin-binding proteins in Streptococcus pneumoniae D39.

Kinetics of β -Lactam Interactions with Penicillin-Susceptible and -Resistant Penicillin-Binding Protein 2x Proteins from Streptococcus pneumoniae: Involvement of Acylation and Deacylation in β -Lactam Resistance

A low-affinity penicillin-binding protein 2x variant is required for heteroresistance in Streptococcus pneumoniae.

Heteroresistance to penicillin in Streptococcus pneumoniae is the ability of subpopulations to grow at a higher antibiotic concentration than expected from the MIC. This may render conventional resistance testing unreliable and lead to therapeutic failure. We investigated the role of the primary β-lactam resistance determinants, penicillin-binding protein 2b (PBP2b) and PBP2x, and the secondary...

DENS - Clinical Dental Therapeutics Lecture 4 Pharmacology of Metronidazole and Antifungal Agents

II. The occurrence of modified penicillin-binding sites Modified PBPs have a lower affinity for β-lactam antibiotics, requiring clinically unattainable concentrations of the drug to effect its bactericidal activity Example: penicillin resistance in Streptococcus pneumoniae (pneumococcus) is caused by altered PBPs I. Production of β-lactamases This family of enzymes can inactivate penicillins by...

Selective penicillin-binding protein imaging probes reveal substructure in bacterial cell division.

The peptidoglycan cell wall is a common target for antibiotic therapy, but its structure and assembly are only partially understood. Peptidoglycan synthesis requires a suite of penicillin-binding proteins (PBPs), the individual roles of which are difficult to determine because each enzyme is often dispensable for growth perhaps due to functional redundancy. To address this challenge, we sought ...

Acquisition of five high-Mr penicillin-binding protein variants during transfer of high-level beta-lactam resistance from Streptococcus mitis to Streptococcus pneumoniae.

Penicillin-resistant isolates of Streptococcus pneumoniae generally contain mosaic genes encoding the low-affinity penicillin-binding proteins (PBPs) PBP2x, PBP2b, and PBP1a. We now present evidence that PBP2a and PBP1b also appear to be low-affinity variants and are encoded by distinct alleles in beta-lactam-resistant transformants of S. pneumoniae obtained with chromosomal donor DNA from a St...