Figure 3. Physical and biochemical evidence for the proposed mechanism of arylomycin resistance.

(A) Crystal structure of E. coli SPase in complex with arylomycin A₂ (PDB ID 1T7D) (Paetzel et al., 2004). Hydrogen-bonds observed in the crystal structure are shown in green, while the potential hydrogen bond prevented by Pro⁸⁴ is shown in red. Equilibrium binding affinities of arylomycin for Pro- and Ser- variants of E. coli (B) and S. aureus (C) SPases. Data points and bars represent average values and standard deviations within a single experiment. K_D values shown are the average of three independent experiments. See also Figure S2.