Fig. 5.

Comparison of E. coli FabZ and FabA substrate binding pockets. (A) FabZ (cyan and green) and AcpP (gray) with an ordered α3-β3 loop (red). The binding pocket (orange surface) is wide at the top with a narrow terminus and is long enough to accommodate C14 substrates. Key amino acids and the DH6 cross-linker are shown as sticks. (B) FabA (cyan and green) and AcpP (gray). The α1-β2 loop (red) defines the end of the binding pocket (gray surface), which is optimal for C10 substrates. Key amino acids and the DH10 cross-linker are shown as sticks.