改造非磷酸转移酶葡萄糖转运途径强化解淀粉芽胞杆菌合成L-酪氨酸

Engineering of the non-phosphotransferase glucose transport system for enhancing L-tyrosine production in Bacillus amyloliquefaciens

L-酪氨酸是一种重要的营养必需氨基酸,广泛应用于食品、医药、化妆品等行业。非磷酸转移酶葡萄糖转运途径是细菌吸收转运葡萄糖的重要途径,对细菌的新陈代谢具有显著的影响。以解淀粉芽胞杆菌HZΔptsH为出发菌株,表达了不同物种来源的葡萄糖转运蛋白编码基因,探究非磷酸转移酶葡萄糖转运途径基因对解淀粉芽胞杆菌合成L-酪氨酸的影响。摇瓶发酵结果表明,HZΔptsH强化表达自身来源葡萄糖转运蛋白编码基因glcP后,L-酪氨酸产量提高了22%,而表达大肠杆菌的galP基因和谷氨酸棒状杆菌的idolT 1基因对L-酪氨酸产量没有显著性的影响。研究证实,过表达解淀粉芽胞杆菌自身glcP基因是一种有效的L-酪氨酸强化策略,该研究为后续解淀粉芽胞杆菌合成L-酪氨酸的代谢工程育种提供了借鉴。

As an important nutritional essential amino acid,L-tyrosine was widely used in food,medical,cosmetics and other industries.The non-phosphotransferase glucose transport pathway was a key way for bacteria to absorb glucose,which had significant effect on the metabolism of bacteria.In this study,the Bacillus amyloliquefaciens HZΔptsH was used as the original strain.Different genes of glucose transporters were expressed to strengthen the glucose absorption transport,and their effects on the biosynthesis of L-tyrosine were investigated.Flasks fermentation results showed that the yield of L-tyrosine was improved by 22%after expression of the native glucose transporter gene glcP in HZΔptsH.Wherein,overexpressing the galP gene from Escherichia coli and idolT1 gene from Corynebacterium glutamicum showed no significant effect on L-tyrosine production.This study confirmed that overexpressing the native glcP gene of B.amyloliquefaciens was an effective strategy for enhancing L-tyrosine production,which provided the reference for further metabolic engineering breeding of B.amyloliquefaciens for L-tyrosine synthesis.