ABSTRACT
Recently, many amylase genes and cDNAs have been cloned and expressed in the yeast Saccharomyces cerevisiae and in fungi. Introduction of multicopy or engineered amylase genes into fungi should further elevate the efficiency of enzyme production. Many amylase genes (or cDNAs) have been cloned from bacteria, yeasts, fungi, plants, and animals. Glucoamylase is produced by many fungi, especially, Rhizopus oryzae and A. niger. The Rhizopus and Aspergillus glucoamylases contain the raw starch-binding site in their NH2- and COOH-termini, respectively. Recent developments in transformation systems for several industrially important fungi have allowed more efficient production of amylases and created novel fungi with desired efficiency to ensure the successful manipulation in industry. Although it is well known that hydrolytic activity per mole of amylase is considerably low compared with other hydrolytic enzymes, no systematic studies have yet been done to create a superamylase with higher specific activity.
