Chains and heterogens:
PDB Chain Sequences:
>1c91A (A:) kqgptsvayvevnnnsmlnvgkytladgggnafdvavifaaninydtgtktaylhfnenv qrvldnavtqirplqqqgikvllsvlgnhqgagfanfpsqqaasafakqlsdavakygld gvdfdddyaeygnngtaqpndssfvhlvtalranmpdkiislynigpaasrlsyggvdvs dkfdyawnpyygtwqvpgialpkaqlspaaveigrtsrstvadlarrtvdegygvyltyn ldggdrtadvsaftrelygseavrt