Chain A ( P471 V472 A473 L474 G475 M476 D478 R481 V552 F553 V554 K555 L556 L557 V558 H559 G560 E561 P562 V563 I564 R565 P566 H567 S570 S571 V572 C600 L601 A602 V603 L604 G605 R606 A607 W621 N622 V623 I624 R625 Y626 S627 L628 Q629 K630 L631 R632 L633 V634 R635 W636 L637 L638 K639 F642 Q643 R645 R646 A650 T651 E652 A653 G654 F655 E656 D657 E658 A659 K660 T661 S662 A663 R664 D665 A666 A667 Y670 V691 H692 M693 A694 L695 C696 A697 V698 N699 L700 A701 E702 C703 A704 E705 E706 K707 I708 L713 H717 F739 L746 H751 )