Figure 4 - full size

Figure 4.
Figure 4: Pre-attack conformation of the substrates. The hydroxyl group representing the -amino group of the A-site substrate, CChPmn (purple) is in position to attack the ester group of the P-site substrate CCApcb (green). It is within hydrogen-bonding distance of N3 of A2486(2451) and the 2' hydroxyl group of the P-site substrate. In this ground state, the reactive groups are 3.7 Å apart.