Genetically engineered bacterium for heterologous expression of xanthan gum endonuclease and application of genetically engineered bacterium

• Main Authors: GAO MINJIE, YANG GUOSHUAI, JIANG YUN, LI ZHITAO, ZHAN XIAOBEI
• Format: Patent
• Language: Chinese; English
• Published: 13.07.2021
• Subjects: BEER; BIOCHEMISTRY; CHEMISTRY; COMPOSITIONS THEREOF; CULTURE MEDIA; ENZYMOLOGY; FERMENTATION OR ENZYME-USING PROCESSES TO SYNTHESISE A DESIREDCHEMICAL COMPOUND OR COMPOSITION OR TO SEPARATE OPTICAL ISOMERSFROM A RACEMIC MIXTURE; METALLURGY; MICROBIOLOGY; MICROORGANISMS OR ENZYMES; MUTATION OR GENETIC ENGINEERING; PROCESSES USING MICROORGANISMS; PROPAGATING, PRESERVING OR MAINTAINING MICROORGANISMS; SPIRITS; VINEGAR; WINE

The invention discloses a genetically engineered bacterium for heterologous expression of xanthan gum endonuclease and application of the genetically engineered bacterium, and belongs to the technical field of genetic engineering. The xanthan gum incision enzyme gene EX, the promoter P43 and the signal peptide PhoD are expressed in bacillus subtilis, so that the xanthan gum incision enzyme is efficiently expressed, and the highest enzyme activity can reach 38U/mL. According to different industrial requirements on relative molecular weights of xanthan gum degradation products, reaction conditions of enzymatic reaction of the xanthan gum incision enzyme can be adjusted, and reaction is performed for 4-16 hours under the conditions that the pH is 5-8, the temperature is 35-55 DEG C and the rotating speed is 0-200 r/min, so that low-molecular-weight xanthan gum with different relative molecular weights is obtained. 本发明公开了一种异源表达黄原胶内切酶的基因工程菌及应用，属于基因工程技术领域。本发明通过在枯草芽孢杆菌中表达黄原胶内切酶基因EX，启动子P43和信号肽PhoD，使黄原胶内切酶高效表达，酶活最高可达到