A retrospect of the structure determination of Taka-amylase A

Abstract The 3D structure of Taka-amylase A was determined by X-ray crystal analysis at 3 Å resolution by Masao Kakudo’s laboratory at the Institute for Protein Research, Osaka University, in 1980. Seven kinds of heavy atom derivatives were used for phase determination. There are three copies of Taka-amylase molecules in the asymmetric unit, which improved the quality of electron density maps, leading to the completion of a molecular model with 478 amino acids. The structure determination process in those days is described briefly.