Chains and heterogens:
PDB Chain Sequences:
>1i91A (A:) hhwgygkhngpehwhkdfpiakgerqspvdidthtakydpslkplsvsydqatslrilnn ghafnvefddsqdkavlkggpldgtyrliqfhfhwgsldgqgsehtvdkkkyaaelhlvh wntkygdfgkavqqpdglavlgiflkvgsakpglqkvvdvldsiktkgksadftnfdprg llpesldywtypgslttppllecvtwivlkepisvsseqvlkfrklnfngegepeelmvd nwrpaqplknrqikasfk