Chain A ( Q365 F366 G367 S368 A369 I370 K371 P372 V374 Y375 P413 R414 N415 Y416 S417 K419 A429 L430 S431 H432 S433 L434 N435 L436 T438 I439 V469 L470 G471 N535 A536 N539 G540 T541 G542 S543 K555 T556 G557 S558 S559 N560 Y562 W566 F567 G591 T593 G594 G595 V596 A599 P600 )