Chains and heterogens:
PDB Chain Sequences:
>1pqaA (A:) ivggtsasagdfpfivsisrnggpwcggsllnantvltaahcvsgyaqsgfqiragslsr tsggitsslssvrvhpsysgnnndlailklstsipsggnigyarlaasgsdpvagssatv agwgatseggsstpvnllkvtvpivsratcraqygtsaitnqmfcagvssggkdscqgds ggpivdssntligavswgngcarpnysgvyasvgalrsfidtya