>1r20A (A:) observed residues (from ATOM records) qelsierllemeslvadpseefqflrvgpdsnvppkfrapvsslcqignkqiaalvvwar diphfsqlemedqillikgswnelllfaiawrsmefltettsppqlmclmpgmtlhrnsa lqagvgqifdrvlselslkmrtlrvdqaeyvalkaiillnpdvkglknrqevevlrekmf lcldeycrrsrsseegrfaalllrlpalrsislksfehlfffhlvadtsiagyirdalr