Beta-galactosidase derived from bacillus circulans

Patent metadata

Field	Value
Publication number	US-9516888-B2
Application number	US-201013375860-A
Country	US
Kind code	B2
Filing date	Apr 23, 2010
Priority date	Jun 5, 2009
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

Disclosed is a novel β-galactosidase. Specifically disclosed are a β-galactosidase derived from Bacillus circulans and a gene for the β-galactosidase. The β-galactosidase can be used, for example, in the production of milk, dairy products, fermented dairy products, galacto-oligosaccharides or supplements for foods.

First claim

The invention claimed is:

1. An enzyme preparation comprising a mixture of isolated β-galactosidase enzymes obtained from Bacillus circulans,
wherein the mixture of enzymes comprises enzymes selected from the group consisting of SEQ ID NO: 8, SEQ ID NO: 9, SEQ ID NO: 10, a polypeptide having at least 90% identity to SEQ ID NO: 8, a polypeptide having at least 90% identity to SEQ ID NO: 9, and a polypeptide having at least 90% identity to SEQ ID NO: 10,
wherein SEQ ID NO: 8, SEQ ID NO: 9, and SEQ ID NO: 10 are c-terminus truncations of native β-galactosidase, and
wherein the enzymes have decreased p-nitrophenyl-β-D-galactopyranoside (ONPG) hydrolyzing activity relative to the native β-galactosidase and/or increased lactose hydrolyzing activity relative to the native β-galactosidase.

2. The enzyme preparation of claim 1 , wherein the base sequence encoding SEQ ID NOs: 8, 9, or 10; or polypeptides having at least 90% identity to SEQ ID NOs: 8, 9, or 10 comprises a DNA sequence selected from the group consisting of the following (a) to (c):
(a) an isolated DNA that hybridizes to the full complement sequence of SEQ ID NO: 5 under stringent conditions comprising incubation at about 42° C. to about 50° C. in 50% formamide, 10×SSC (0.15M NaCl, 15 mM sodium citrate, pH 7.0), 5×Denhardt's solution, 1% SDS, 10% dextran sulfate, 10 μg/ml denatured salmon sperm DNA, and 50 mM phosphate buffer (pH 7.5) and, thereafter, washed with 0.1×SSC and 0.1% SDS at about 65° C. to about 70° C.;
(b) an isolated DNA having at least 99% identity to SEQ ID NO: 5 and encoding a protein having a β-galactosidase activity; and
(c) an isolated DNA comprising the nucleotide sequence of SEQ ID NO: 5.

3. The enzyme preparation of claim 1 , wherein the polypeptide has at least 95% sequence identity to SEQ ID NOs: 8, 9, or 10.

4. The enzyme preparation of claim 1 , wherein the polypeptide has at least 98% sequence identity to SEQ ID NOs: 8, 9, or 10.

5. The enzyme preparation of claim 1 , wherein the polypeptide has at least 99% sequence identity to SEQ ID NOs: 8, 9, or 10.

Assignees

• Katase Toru
• Hoshi Yukiko
• Nagaya Miho
• Yamaguchi Shotaro
• Minoda Masashi
• Nakanishi Kazuhiro
• Amano Enzyme Inc

Inventors

• Katase Toru
• Hoshi Yukiko
• Nagaya Miho
• Yamaguchi Shotaro
• Minoda Masashi
• Nakanishi Kazuhiro

Classifications

• A61P3/00

  Drugs for disorders of the metabolism (of the blood or the extracellular fluid A61P7/00) · CPC title

• A61P3/02

  Nutrients, e.g. vitamins, minerals · CPC title

• A23L29/06

  Enzymes · CPC title

• A61K38/47

  acting on glycosyl compounds (3.2), e.g. cellulases, lactases · CPC title

• C12N15/63 Primary

  Introduction of foreign genetic material using vectors; Vectors; Use of hosts therefor; Regulation of expression · CPC title