Chains and heterogens:
PDB Chain Sequences:
>1pa2A (A:) mqlnatfysgtcpnasaivrstiqqalqsdtrigaslirlhfhdcfvngcdasillddtg siqseknagpnvnsargfnvvdniktalenacpgvvscsdvlalaseasvslaggpswtv llgrrdsltanlaganssipspieslsnitfkfsavglntndlvalsgahtfgrarcgvf nnrlfnfsgtgnpdptlnstllstlqqlcpqngsastitnldlstpdafdnnyfanlqsn dgllqsdqelfsttgsstiaivtsfasnqtlffqafaqsminmgnispltgsngeirldc kkvngs