Question

Beta-lactamases bind to penicillin-binding proteins, bind to peptides, prevent the linking of glycan chains in peptidoglycan, or break the beta-lactam ring?

1) bind to penicillin-binding proteins
2) bind to peptides
3) prevent the linking of glycan chains in peptidoglycan
4) break the beta-lactam ring

Answer 1

Beta-lactamases are enzymes that break the β-lactam ring of antibiotics, rendering them inactive. They prevent the linking of glycan chains in the peptidoglycan layer, which leads to degradation of the cell wall.

Step-by-step explanation:

Beta-lactamases are bacterially produced enzymes that break the β-lactam ring of susceptible β-lactam antimicrobials, rendering them inactive and conferring resistance. They cleave the ring by performing an acyl substitution reaction, irreversibly inhibiting the enzyme transpeptidase, which catalyzes the formation of a peptide bond in the cell wall's peptidoglycan layer. This prevents the linking of glycan chains and ultimately results in the degradation of the cell wall, leading to cytolysis.