Chains and heterogens:
PDB Chain Sequences:
>1ptkA (A:) aaqtnapwglarisstspgtstyyydesagqgscvyvidtgieashpefegraqmvktyy yssrdgnghgthcagtvgsrtygvakktqlfgvkvlddngsgqystiiagmdfvasdknn rncpkgvvaslslgggysssvnsaaarlqssgvmvavaagnnnadarnyspasepsvctv gasdrydrrssfsnygsvldifgpgtsilstwiggstrsisgtsmatphvaglaaylmtl gkttaasacryiadtankgdlsnipfgtvnllaynnyqa