FIGURE 5.

Changes in the conformation of CLg1GBSS accompanying acceptor binding. ADP and acarbose from chain A of the CLg1GBSS crystal, are shown as sticks with gray carbons. The conformation of chain A from Tyr14 to Gly19 is shown as a stick model with green carbons, while the conformation of the same segment in chain B is shown semi-transparent and with pink carbons. The loop around Tyr101 is shown as a cyan thin ribbon for the α-carbon trace with key amino acids as sticks with cyan carbons. The whole loop is disordered and absent from the model for chain B. Purple dashes represent interactions at less than 3.2 Å. Tyr101 is also participating in a stacking interaction with a glucosyl moiety in acarbose. The orange circles highlight the movement of the side chain of Thr17 upon acarbose binding.