Heterologous expression of an aspergillus kawachi acid-stable alpha amylase and applications in granular starch hydrolysis

摘要

The present invention relates to a granular starch hydrolyzing enzyme compositioncomprising an acid stable alpha amylase (asAA) having granular starch hydrolyzingactivity. The invention also relates to a one-step method for producing an alcoholwhich comprises contacting a granular starch substrate with an acid-stablealpha amylase (asAA) having granular starch hydrolyzing (GSH) activity anda glucoamylase (GA) in a fermentation step which also comprises ethanologenicmicroorganisms at a temperature of 25 - 40°C to obtain a fermentation brothhaving 5 to 20% ethanol.