High-enzyme-activity D-psicose 3-epimerase mutant and application thereof

• Main Authors: REN HU, ZHU YINGYING, ZHANG WENLI, MU WANMENG, LI JIN, SHI TING, NI DAWEI, XU WEI
• Format: Patent
• Language: Chinese; English
• Published: 04.07.2023
• Subjects: BAKERY PRODUCTS; BAKING; BEER; BIOCHEMISTRY; CHEMISTRY; COMPOSITIONS THEREOF; CULTURE MEDIA; EDIBLE DOUGHS; ENZYMOLOGY; FOODS OR FOODSTUFFS; FOODS, FOODSTUFFS, OR NON-ALCOHOLIC BEVERAGES, NOT COVERED BYSUBCLASSES A23B - A23J; HUMAN NECESSITIES; HYGIENE; MEDICAL OR VETERINARY SCIENCE; METALLURGY; MICROBIOLOGY; MICROORGANISMS OR ENZYMES; MUTATION OR GENETIC ENGINEERING; PREPARATIONS FOR MEDICAL, DENTAL, OR TOILET PURPOSES; PRESERVATION OF FOODS OR FOODSTUFFS, IN GENERAL; PRESERVATION THEREOF; PROCESSES USING MICROORGANISMS; PROPAGATING, PRESERVING OR MAINTAINING MICROORGANISMS; SPIRITS; THEIR PREPARATION OR TREATMENT, e.g. COOKING, MODIFICATION OFNUTRITIVE QUALITIES, PHYSICAL TREATMENT; THEIR TREATMENT, NOT COVERED BY OTHER CLASSES; TREATMENT, e.g. PRESERVATION, OF FLOUR OR DOUGH, e.g. BYADDITION OF MATERIALS; VINEGAR; WINE

The invention discloses a high-enzyme-activity D-psicose 3-epimerase mutant and application thereof, and belongs to the technical field of gene engineering of enzymes. According to the invention, D-psicose 3-epimerase derived from Thermoclostridium caencola is used as a parent, cysteine at the 258th site is mutated into histidine by using a gene mutation technology, a single-site mutant C258H is obtained, and the enzyme activity of the single-site mutant C258H is improved from 242.4 U/mg of a wild type enzyme to 387.8 U/mg, which is increased by 60.0%. The discovery has an important research value for industrial preparation of D-psicose. 本发明公开了一种高酶活D-阿洛酮糖3-差向异构酶突变体及其应用，属于酶的基因工程技术领域。本发明以来源于Thermoclostridium caenicola的D-阿洛酮糖3-差向异构酶作为亲本，利用基因突变技术，将第258位的半胱氨酸突变为组氨酸，获得单点突变体C258H，其酶活得到了提高，由野生型酶的242.4U/mg提高到387.8U/mg，增加了60.0％。这一发现对于工业化制备D-阿洛酮糖具有重要的研究价值。