Chains and heterogens:
PDB Chain Sequences:
>1b4xA (A:) mfenitaapadpilgladlfraderpgkinlgigvykdetgktpvltsvkkaeqyllene ttknylgidgipefgrctqellfgkgsalindkrartaqtpggtgalrvaadflakntsv krvwvsnpswpnhksvfnsaglevreyayydaenhtldfdalinslneaqagdvvlfhgs chnptgidptleqwqtlaqlsvekgwlplfdfayqgfargleedaeglrafaamhkeliv assysknfglynervgactlvaadsetvdrafsqmkaairanysnppahgasvvatilsn dalraiweqeltdmrqriqrmrqlfvntlqekganrdfsfiikqngmfsfsgltkeqvlr lreefgvyavasgrvnvagmtpdnmaplceaivavl