Chains and heterogens:
PDB Chain Sequences:
>1m73E (E:) engytyedykntaewllshtkhrpqvaiicgsglggltdkltqaqifdyseipnfprstv pghagrlvfgflngracvmmqgrfhmyegyplwkvtfpvrvfhllgvdtlvvtnaaggln pkfevgdimlirdhinlpgfsgqnplrgpnderfgdrfpamsdaydrtmrqralstwkqm geqrelqegtyvmvagpsfetvaecrvlqklgadavgmstvpevivarhcglrvfgfsli tnkvimdyeslekanheevlaagkqaaqkleqfvsilmasiplpdkas