>3l57B (B:) observed residues (from ATOM records)
mldittitrqnvtsvvgftswqgtgaealglsgdvesarfkellvgeidtfthmqrhkke
rlgydltfsapkgvsmqalihgdktiieahekavaaavreaeklaqarttrqgksvtqnt
nnlvvatfrhetsrldpdlhthafvmnmtqredgqwralkndelmrnkmhlgdvykqela
leltkagyelrynsknntfdmah