>2xu4A (A:) observed residues (from ATOM records)
aprsvdwrekgyvtpvknqgqcgscwafsatgalegqmfrktgrlislseqnlvdcsgpq
gnegcngglmdyafqyvqdnggldseesypyeateesckynpkysvandtgfvdipkqek
almkavatvgpisvaidaghesflfykegiyfepdcssedmdhgvlvvgygfestnnkyw
lvknswgeewgmggyvkmakdrrnhcgiasaasyptv