Chains and heterogens:
PDB Chain Sequences:
>1k4dA (A:) qvqlqqpgaelvkpgasvklsckasgytftsdwihwvkqrpghglewigeiipsygrany nekiqkkatltadkssstafmqlssltsedsavyycarergdgyfavwgagttvtvssak ttppsvyplapgsaaqtnsmvtlgclvkgyfpepvtvtwnsgslssgvhtfpavlqsdly tlsssvtvpssswpsetvtcnvahpasstkvdkkivprd
>1k4dB (B:) dilltqspailsvspgervsfscrasqsigtdihwyqqrtngsprllikyasesisgips rfsgsgsgtdftlsinsvesedianyycqqsnrwpftfgsgtkleikradaaptvsifpp sseqltsggasvvcflnnfypkdinvkwkidgserqngvlnswtdqdskdstysmsstlt ltkdeyerhnsytceathktstspivksfnrn
>1k4dC (C:) salhwraagaatvllvivllagsylavlaergapgaqlitypralwwsvetattvgygdl ypvtlwgrcvavvvmvagitsfglvtaalatwfvgreqerrgh