Chains and heterogens:
PDB Chain Sequences:
>1k4cA (A:) qvqlqqpgaelvkpgasvklsckasgytftsdwihwvkqrpghglewigeiipsygrany nekiqkkatltadkssstafmqlssltsedsavyycarergdgyfavwgagttvtvssak ttppsvyplapgsaaqtnsmvtlgclvkgyfpepvtvtwnsgslssgvhtfpavlqsdly tlsssvtvpssswpsetvtcnvahpasstkvdkkivprd
>1k4cB (B:) dilltqspailsvspgervsfscrasqsigtdihwyqqrtngsprllikyasesisgips rfsgsgsgtdftlsinsvesedianyycqqsnrwpftfgsgtkleikradaaptvsifpp sseqltsggasvvcflnnfypkdinvkwkidgserqngvlnswtdqdskdstysmsstlt ltkdeyerhnsytceathktstspivksfnrn
>1k4cC (C:) mapmlsgllarlvklllgrhgsalhwraagaatvllvivllagsylavlaergapgaqli typralwwsvetattvgygdlypvtlwgrcvavvvmvagitsfglvtaalatwfvgreqe rrgh
>1k4cC (C:) salhwraagaatvllvivllagsylavlaergapgaqlitypralwwsvetattvgygdl ypvtlwgrcvavvvmvagitsfglvtaalatwfvgreqerrgh