Godo Shusei Co., Ltd.

Hirofumi Horiguchi

Jun Yoshikawa

Kazuma Shiota

Tomoko Sato

Masahiro Baba

Ryoko Sano

Shun Ogawa

Ai Iyotani

Junki Ogasawara

Naoki Nagahata

Provided are a novel isoamylase improved in optimum temperature, and more specifically, improved in heat resistance, and a process for producing the isoamylase. An isoamylase having at least one amino acid mutation selected from the group consisting of D268A, M277I, A549P, A554P and A580T in an isoamylase consisting of an amino acid sequence represented by SEQ ID No: 1 or an isoamylase consisting of the amino acid sequence represented by SEQ ID No: 1 and having deletion, substitution or insertion of one to several amino acid residues.

Heat resistant isoamylase

[Problem] To provide a lactase solution having excellent thermal stability. [Solution] A lactase solution in which the ratio of a lactase fraction having a molecular weight of about 120 kDa measured by SDS polyacrylamide gel electrophoresis is 20% or more.

Lactase solution and dairy product using same

An isoamylase having improved heat resistance and an industrial method for producing maltose from starch. The isoamylase is an isoamylase consisting of the amino acid sequence represented by SEQ ID NO: 1 or an isoamylase resulting from deletion, substitution, or insertion of one to several amino acid residues in the amino acid sequence represented by SEQ ID NO: 1, wherein at least valine at amino acid number 515 and methionine at amino acid number 570 are mutated to other amino acids.

Heat-resistant isoamylase

Growing community of inventors

Matsudo, Japan

Hirofumi Horiguchi