PROCESS FOR PRODUCING HIGH GLUCOSE COMPOSITIONS BY SIMULTANEOUS LIQUEFACTION AND SACCHARIFICATION OF STARCH SUBSTRATES

摘要

Fungal glucoamylases from Aspergillus fumigatus that are expressed in Trichoderma reesei host cells (AfGATR) are provided. AfGATRs, including AfGA1TR and AfGA2TR, exhibit high activity at elevated temperatures and at low pH, so AfGATRs can be used efficiently in a simultaneous liquefaction and saccharification process in the presence of alpha amylase, such as Aspergillus kawachii alpha-amylase (AkAA). This greatly reduces the combined run time of liquefaction and saccharification reaction, where the pH and temperature must be readjusted for optimal use of the alpha-amylase or glucoamylase.

主权项

1. A method of simultaneously liquefying and saccharifying a composition comprising starch to produce a composition comprising glucose, wherein said method comprises:
(i) contacting said composition comprising starch with an isolated AfGATR, or variant thereof, having at least 80% sequence identity to SEQ ID NO: 12 or 13 and an α-amylase; and (ii) liquefying and saccharifying the composition comprising starch above the gelatinization temperature of said starch in the same reaction vessel to produce said glucose composition; wherein said AfGATR, or variant thereof, and said α-amylase catalyze the saccharification of the composition comprising starch to the composition comprising glucose.