Chains and heterogens:
PDB Chain Sequences:
>1r3kA (A:) dilltqspailsvspgervsfscrasqsigtdihwyqqrtngsprllikyasesisgips rfsgsgsgtdftlsinsvesedianyycqqsnrwpftfgsgtkleikradaaptvsifpp sseqltsggasvvcflnnfypkdinvkwkidgserqngvlnswtdqdskdstysmsstlt ltkdeyerhnsytceathktstspivksfnrn
>1r3kB (B:) qvqlqqpgaelvkpgasvklsckasgytftsdwihwvkqrpghglewigeiipsygrany nekiqkkatltadkssstafmqlssltsedsavyycarergdgyfavwgagttvtvssak ttppsvyplapgsaaqtnsmvtlgclvkgyfpepvtvtwnsgslssgvhtfpavlqsdly tlsssvtvpssswpsetvtcnvahpasstkvdkkivprd
>1r3kC (C:) mapmlsgllarlvklllgrhgsalhwraagaatvllvivllagsylavlaergapgaqli typralwwsvetattvgygdlypvtlwgrcvavvvmvagitsfglvtaalatwfvgreqe rrgh
>1r3kC (C:) salhwraagaatvllvivllagsylavlaergapgaqlitypralwwsvetattvgygdl ypvtlwgrcvavvvmvagitsfglvtaalatwfvgreqerrgh