Chains and heterogens:
PDB Chain Sequences:
>1xtiA (A:) gspghmssgfrdfllkpellraivdcgfehpsevqhecipqailgmdvlcqaksgmgkta vfvlatlqqlepvtgqvsvlvmchtrelafqiskeyerfskympnvkvavffgglsikkd eevlkkncphivvgtpgrilalarnkslnlkhikhfildecdkmleqldmrrdvqeifrm tphekqvmmfsatlskeirpvcrkfmqdpmeifvddetkltlhglqqyyvklkdneknrk lfdlldvlefnqvvifvksvqrcialaqllveqnfpaiaihrgmpqeerlsryqqfkdfq rrilvatnlfgrgmdiervniafnydmpedsdtylhrvaragrfgtkglaitfvsdenda kilndvqdrfevniselpdeidissyieqtr
>1xtiA (A:) gfrdfllkpellraivdcgfehpsevqhecipqailgmdvlcqaksgmgktavfvlatlq qlepvtgqvsvlvmchtrelafqiskeyerfskympnvkvavffgglsikkdeevlkknc phivvgtpgrilalarnkslnlkhikhfildecdkmleqldmrrdvqeifrmtphekqvm mfsatlskeirpvcrkfmqdpmeifvddetkltlhglqqyyvklkdneknrklfdlldvl efnqvvifvksvqrcialaqllveqnfpaiaihrgmpqeerlsryqqfkdfqrrilvatn lfgrgmdiervniafnydmpedsdtylhrvaragrfgtkglaitfvsdendakilndvqd rfevniselpdeidissyieq