The N···H hydrogen bond strength in the transition state at the limiting step determines the reactivity of cephalosporins in the active site of L1 metallo-β-lactamase

The combined quantum mechanics/molecular mechanics investigation followed by the detailed electron density analysis for 9 cephalosporin–L1 metallo-β-lactamase complexes revealed correlation between the N···H hydrogen bond strength in the transition state at the limiting step and the reactivity of cephalosporin compounds. The stronger interactions were typical of the less reactive species.