>1sr4A (A:) observed residues (from ATOM records)
lnllsssgpnrqvlpsepsnfmtlmgqngalltvwalakrnwlwaypniysqdfgnirnw
kmepgkhreyfrfvnqslgtcveaygnglihdicsldklaqefellptdsgavviksvsq
grcvtynpvsttfystvtlsvcdgatepsrdqtwylappvleatavn