Chains and heterogens:
PDB Chain Sequences:
>1a23_ (-) aqyedgkqyttlekpvagapqvleffsffcphcyqfeevlhisdnvkkklpegvkmtkyh vnfmggdlgkdltqawavamalgvedkvtvplfegvqktqtirsasdirdvfinagikge eydaawnsfvvkslvaqqekaaadvqlrgvpamfvngkyqlnpqgmdtsnmdvfvqqyad tvkylsekk