Molecular Cloning of the Glucoamylase I Gene of Aspergillus awamori var. kawachi for Localization of the Raw-starch-affinity Site

Abstract

The raw-starch-digesting glucoamylase I (GAI) of Aspergillus awamori var. kawachi contains a glycopeptide I (Gp-I) region as the raw-starch-affinity site essential for its raw-starch-adsorption and raw-starch-digestion. Molecular cloning of the GAI gene and analysis of its nucleotide sequence revealed some nucleotide replacements, in comparison with the Aspergillus niger and Aspergillus awamori glucoamylase genes. The deduced total ami no acid sequence of GAI contained 35 replacements and one deletion, of a mi no acid residues, and therefore a total of 615 residues, in comparison with the A. niger and A. awamori glucoamylases. The raw-starch-adsorbable Gp-I region in GAI was located between Ala⁴⁷⁰ and Val⁵¹⁴ near the C-terminal, consisting of ATGG-TTTTATTTGSGGVTSTSKTTTTASKTSTTTSSTSCTTPTAV.