Chain A ( R172 Q225 G226 A227 A228 G229 I230 D305 T350 R351 P352 V353 A354 L355 E356 K357 L358 I370 L371 G372 F373 S374 R378 E403 V404 L405 F406 T407 M408 C409 F410 I411 P412 L413 V414 C415 T439 Q480 H522 M523 T524 E527 Y565 G566 K567 F568 K570 G571 Y572 L573 I574 F575 V577 R578 I623 Q624 P625 S626 L628 E629 Y632 E636 N656 S658 T659 R660 M661 D662 M664 )