Final answer:
Beta-lactam antibiotics interfere with the active sites in bacteria by competitively binding to and inhibiting penicillin-binding proteins (PBPs).
Step-by-step explanation:
Beta-lactam antibiotics interfere with the active sites in bacteria by competitively binding to and inhibiting penicillin-binding proteins (PBPs). Penicillin-binding proteins are enzymes involved in the cell wall synthesis of bacteria. By inhibiting these proteins, beta-lactam antibiotics prevent the formation of a functional cell wall, leading to the death of the bacteria.