Chains and heterogens:
PDB Chain Sequences:
>1po21 (1:) aatsrdalpnteasgpthskeipaltavetgatnplvpsdtvqtrhvvqhrsrsessies ffargacvtimtvdnpasttnkdklfavwkitykdtvqlrrklefftysrfdmeltfvvt anftetnnghalnqvyqimyvppgapvpekwddytwqtssnpsifytygtaparisvpyv gisnayshfydgfskvplkdqsaalgdslygaaslndfgilavrvvndhnptkvtskirv ylkpkhirvwcprppravayygpgvdykdgtltplstkdltty
>1po22 (2:) eacgysdrvlqltlgnstittqeaansvvaygrwpeylrdseanpvdqptepdvaacrfy tldtvswtkesrgwwwklpdalrdmglfgqnmyyhylgrsgytvhvqcnaskfhqgalgv favpemclagdsntttmhtsyqnanpgekggtftgtftpdnnqtsparrfcpvdyllgng tllgnafvfphqiinlrtnncatlvlpyvnslsidsmvkhnnwgiailplaplnfasess peipitltiapmccefnglrnitlprlq
>1po23 (3:) glpvmntpgsnqyltadnfqspcalpefdvtppidipgevknmmelaeidtmipfdlsat kkntmemyrvrlsdkphtddpilclslspasdprlshtmlgeilnyythwagslkftflf cgsmmatgkllvsyappgadppkkrkeamlgthviwdiglqssctmvvpwisnttyrqti ddsfteggyisvfyqtrivvplstpremdilgfvsacndfsvrllrdtthieqka