Chains and heterogens:
PDB Chain Sequences:
>4mrqA (A:) lpasifraydirgvvgdtltaetaywigraigseslargepcvavgrdgrlsgpelvkql iqglvdcgcqvsdvgmvptpvlyyaanvlegksgvmltgshnppdyngfkivvagetlan eqiqalreriekndlasgvgsveqvdilpryfkqirddiamakpmkvvvdcgngvagvia pqliealgcsviplycevdgnfpnhhpdpgkpenlkdliakvkaenadlglafdgdgdrv gvvtntgtiiypdrllmlfakdvvsrnpgadiifdvkctrrlialisgyggrpvmwktgh slikkkmketgallagemsghvffkerwfgfddgiysaarlleilsqdqrdsehvfsafp sdistpeinitvtedskfaiiealqrdaqwgegnittldgvrvdypkgwglvrasnttpv lvlrfeadteeeleriktvfrnqlkavdsslpvpf