Chains and heterogens:
PDB Chain Sequences:
>1n21A (A:) qirrsgnyqpalwdsnyiqslntpyteerhldrkaelivqvrillkekmepvqqlelihd lkylglsdffqdeikeilgviynehkcfhnnevekmdlyftalgfrllrqhgfnisqdvf ncfknekgidfkaslaqdtkgmlqlyeasfllrkgedtlelarefatkclqkkldeggne idenlllwirhsldlplhwriqsvearwfidayarrpdmnplifelaklnfniiqathqq elkdlsrwwsrlcfpeklpfvrdrlvesffwavgmfephqhgyqrkmaatiivlatvidd iydvygtldelelftdtfkrwdtesitrlpyymqlcywgvhnyisdaaydilkehgffcl qylrksvvdlveayfheakwyhsgytpsldeylniakisvaspaiisptyftfanashdt avidslyqyhdilclagiilrlpddlgtsyfelargdvpktiqcymketnaseeeavehv kflireawkdmntaiaagypfpdgmvagaanigrvaqfiylhgdgfgvqhsktyehiagl lfepya
>1n21A (A:) qirrsgnyqpalwdsnyiqslntpyteerhldrkaelivqvrillkekmepvqqlelihd lkylglsdffqdeikeilgviynehkcfhkmdlyftalgfrllrqhgfnisqdvfncfkn ekgidfkaslaqdtkgmlqlyeasfllrkgedtlelarefatkclqkklddenlllwirh sldlplhwriqsvearwfidayarrpdmnplifelaklnfniiqathqqelkdlsrwwsr lcfpeklpfvrdrlvesffwavgmfephqhgyqrkmaatiivlatviddiydvygtldel elftdtfkrwdtesitrlpyymqlcywgvhnyisdaaydilkehgffclqylrksvvdlv eayfheakwyhsgytpsldeylniakisvaspaiisptyftfanashdtavidslyqyhd ilclagiilrlpddlgtsyfelargdvpktiqcymketnaseeeavehvkflireawkdm ntaiaagypfpdgmvagaanigrvaqfiylhgdgfgvqhsktyehiagllfepya