Chains and heterogens:
PDB Chain Sequences:
>1bx4A (A:) vrenilfgmgnplldisavvdkdfldkyslkpndqilaedkhkelfdelvkkfkveyhag gstqnsikvaqwmiqqphkaatffgcigidkfgeilkrkaaeahvdahyyeqneqptgtc aacitgdnrslianlaaancykkekhldleknwmlvekarvcyiagffltvspesvlkva hhasennriftlnlsapfisqfykeslmkvmpyvdilfgneteaatfareqgfetkdike iakktqalpkmnskrqriviftqgrddtimatesevtafavldqdqkeiidtngagdafv ggflsqlvsdkplteciraghyaasiiirrtgctfpekpdfh