Chains and heterogens:
PDB Chain Sequences:
>1grnA (A:) mqtikcvvvgdgavgktcllisyttnkfpseyvptvfdnyavtvmiggepytlglfdtag qedydrlrplsypqtdvflvcfsvvspssfenvkekwvpeithhcpktpfllvgtqidlr ddpstieklaknkqkpitpetaeklardlkavkyvecsaltqkglknvfdeailaalepp epkksrrcvll
>1grnB (B:) lpnqqfgvslqhlqeknpeqepipivlretvaylqahalttegifrrsantqvvrevqqk ynmglpvdfdqynelhlpavilktflrelpeplltfdlyphvvgflnidesqrvpatlqv lqtlpeenyqvlrfltaflvqisahsdqnkmtntnlavvfgpnllwakdaaitlkainpi ntftkflldhqgelfpspdpsgl
>1grnB (B:) lpnqqfgvslqhlqeknpeqepipivlretvaylqahalttegifrrsantqvvrevqqk ynmglpvdfdqynelhlpavilktflrelpeplltfdlyphvvgflnidesqrvpatlqv lqtlpeenyqvlrfltaflvqisahsdqnkmtntnlavvfgpnllwakdaaitlkainpi ntftkflldhqgelfps