>1ex4A (A:) observed residues (from ATOM records)
sspgiwqldcthlegkvilvavhvasgyieaevipaetgqetayfllklagrwpvktiht
dngsnftgatvraacdwagikqedgipqsqgvvesmnkelkkiigqvrdqaehlktavqm
avfihnkkrkggiggysagerivdiiatdiqtkelqkqitkiqnfrvyyrdsrnslwkgp
akllwkgegavviqdnsdikvvprrkakiird