Chains and heterogens:
PDB Chain Sequences:
>2st1_ (-) aqsvpygvsqikapalhsqgytgsnvkvavidsgidsshpdlkvaggasmvpsetnpfqd nnshgthvagtvaalnnsigvlgvapsaslyavkvlgadgsgqyswiingiewaiannmd vinmslggpsgsaalkaavdkavasgvvvvaaagnegtsgssstvgypgkypsviavgav dssnqrasfssvgpeldvmapgvsiqstlpgnkygayngtsmasphvagaaalilskhpn wtntqvrsslentttklgdsfyygkglinvqaaaq