biostudies-literatureGyger JSwiss National Science FoundationHoward Hughes Medical InstituteNIAID NIH HHSHHS | NIH | National Institute of Allergy and Infectious DiseasesHoward Hughes Medical Institute (HHMI)e0141924https://www.ebi.ac.uk/biostudies/studies/S-EPMC11253642biostudies-literatureUnknown15(7)<i>Pseudomonas aeruginosa</i> encodes the beta-lactamase AmpC, which promotes resistance to beta-lactam antibiotics. Expression of <i>ampC</i> is induced by anhydro-muropeptides (AMPs) released from the peptidoglycan (PG) cell wall upon beta-lactam treatment. AmpC can also be induced via genetic inactivation of PG biogenesis factors such as the endopeptidase DacB that cleaves PG crosslinks. Mutants in <i>dacB</i> occur in beta-lactam-resistant clinical isolates of <i>P. aeruginosa</i>, but it has remained unclear why DacB inactivation promotes <i>ampC</i> induction. Similarly, the inactivation of lytic transglycosylase (LT) enzymes such as SltB1 that cut PG glycans has also been associated with <i>ampC</i> induction and beta-lactam resistance. Given that LT enzymes are capable of producingmBioA potential space-making role in cell wall biogenesis for SltB1and DacB revealed by a beta-lactamase induction phenotype in <i>Pseudomonas aeruginosa</i>.PMC11253642R01 AI083365U19 AI158028162073Bernhardt TGGyger JCava FTorrens GFumeaux CfalseA potential space-making role in cell wall biogenesis for SltB1and DacB revealed by a beta-lactamase induction phenotype in <i>Pseudomonas aeruginosa</i>.<i>Pseudomonas aeruginosa</i> encodes the beta-lactamase AmpC, which promotes resistance to beta-lactam antibiotics. Expression of <i>ampC</i> is induced by anhydro-muropeptides (AMPs) released from the peptidoglycan (PG) cell wall upon beta-lactam treatment. AmpC can also be induced via genetic inactivation of PG biogenesis factors such as the endopeptidase DacB that cleaves PG crosslinks. Mutants in <i>dacB</i> occur in beta-lactam-resistant clinical isolates of <i>P. aeruginosa</i>, but it has remained unclear why DacB inactivation promotes <i>ampC</i> induction. Similarly, the inactivation of lytic transglycosylase (LT) enzymes such as SltB1 that cut PG glycans has also been associated with <i>ampC</i> induction and beta-lactam resistance. Given that LT enzymes are capable of producing2024-01-01T00:00:00Z2024 Jul2025-04-04T15:01:37.164Z2025-04-04T15:01:37.164ZS-EPMC112536423892039410.1128/mbio.01419-24