Chain A ( G429 H430 G431 D432 C433 E434 E435 L436 Q437 F575 L576 V577 Q578 Y579 F580 T581 R582 F583 T584 E585 I801 V804 N807 K809 Y819 R925 F953 R987 K988 D991 Q996 L999 S1000 F1001 L1002 D1003 D1004 V1005 I1006 P1007 E1008 K1009 D1010 K1011 K1014 )