Chain A ( C311 C314 R316 Y318 S322 S323 L324 R326 H327 S328 V330 H331 W333 R335 C339 K344 V345 F346 A347 L348 A349 E350 Y351 R352 T353 K354 H355 E356 V357 W358 Y365 F374 V375 T376 Y377 Y378 N379 L380 K381 T382 E660 D661 Q662 L663 W664 R665 P666 Y667 Y668 S669 Y670 L924 )