Chains and heterogens:
PDB Chain Sequences:
>2xkrA (A:) mteapdvdladgnfyasrearaayrwmranqpvfrdrnglaaastyqavidaerqpelfs naggirpdqpalpmmidmddpahllrrklvnagftrkrvkdkeasiaalcdtlidavcer gecdfvrdlaaplpmavigdmlgvrpeqrdmflrwsddlvtflsshvsqedfqitmdafa ayndftratiaarradptddlvsvlvssevdgerlsddelvmetlliliggdettrhtls ggteqllrnrdqwdllqrdpsllpgaieemlrwtapvknmcrvltadtefhgtalcagek mmllfesanfdeavfcepekfdvqrnpnshlafgfgthfclgnqlarlelslmtervlrr lpdlrlvaddsvlplrpanfvsglesmpvvftpspplg
>2xkrA (A:) apdvdladgnfyasrearaayrwmranqpvfrdrnglaaastyqavidaerqpelfsnag girpdqpalpmmidmddpahllrrklvnagftrkrvkdkeasiaalcdtlidavcergec dfvrdlaaplpmavigdmlgvrpeqrdmflrwsddlvtflsshvsqedfqitmdafaayn dftratiaarradptddlvsvlvssevdgerlsddelvmetlliliggdettrhtlsggt eqllrnrdqwdllqrdpsllpgaieemlrwtapvknmcrvltadtefhgtalcagekmml lfesanfdeavfcepekfdvqrnpnshlafgfgthfclgnqlarlelslmtervlrrlpd lrlvaddsvlplrpanfvsglesmpvvftpspplg