- Site-directed mutagenesis of histidine 93, aspartic acid 180, glutamic acid 205, histidine 290, and aspartic acid 291 at the active site and tryptophan 279 at the raw starch binding site in barley alpha-amylase 1. Søgaard, M., Kadziola, A., Haser, R., Svensson, B. J. Biol. Chem. (1993)