Chain A ( K132 L134 H135 E136 F137 D138 L140 D142 P143 E144 V145 N442 T443 F448 R453 I457 I458 L459 H460 W462 T478 V479 Q480 T481 N482 P483 Y484 T485 P650 F651 L652 V682 H683 I684 P685 A686 V687 S688 V689 Q690 F691 G692 L695 )