摘要
目的:以课题组构建的钝齿棒杆菌(Corynebacterium crenatum)MT NAGK M4ΔproBΔNcgl1221ΔdtsR1(CCM01)为出发菌株,探究吐温(Tween)对该菌产精氨酸代谢的影响。方法:优化精氨酸发酵及Tween质量浓度,测定菌体生长量、L-精氨酸产量、发酵液残糖量考察Tween 40、Tween 80及Tween 80结合油酸对菌株CCM01产精氨酸的影响;采用实时聚合酶链式反应检测L-精氨酸合成相关基因转录水平。结果:在CCM01菌株发酵中添加Tween 40、Tween 80及Tween 80结合油酸,还原型烟酰胺腺嘌呤二核苷酸(reduced nicotinamide-adenine dinucleotide phosphate,NADPH)供应提升,相应精氨酸产量提高,尤其在Tween 80和油酸按物质的量比1∶0.1添加的培养条件下,与出发菌株CCM01相比,胞内NADPH的生成提升至2.56倍,L-精氨酸产量提高了29.43%;同时,合成NADPH的磷酸戊糖途径相关基因上调,作为L-精氨酸合成途径的负调控因子——脂肪酸响应蛋白FarR编码基因下调,相应的L-精氨酸合成途径相关基因转录水平上调,表明吐温可从两方面提高精氨酸产量。
The effect of Tweens(Tween 40, Tween 80, and Tween 80 combined with oleic acid) on in the metabolism of Corynebacterium crenatum MT NAGK M4 ΔproBΔNcgl1221ΔdtsR1(CCM01) for L-arginine production was investigated by determining biomass concentration, L-arginine concentration and residual sugar levels in the fermented broth. Realtime polymerase chain reaction was used to evaluate the transcription levels of genes related to L-arginine biosynthesis.The results showed that addition of Tween 40, Tween 80, and Tween 80 combined with oleic acid increased the supply of reduced nicotinamide-adenine dinucleotide phosphate(NADPH) and consequently the production of L-arginine. Notably,when Tween 80 and oleic acid were added to the medium at a molar ratio of 1:0.1, NADPH accumulation increased by 2.56 folds and L-arginine production increased by 29.43%. Additionally, the transcription levels of tkt-tal-zwf-opcApgl and gnd involved in NADPH biosynthesis were up-regulated, and the transcription level of the fatty acyl-responsive regulator FarR, a negative regulatory factor of arginine biosynthetic pathway, was down-regulated;accordingly, the transcription levels of gdh, argB and argG were up-regulated. The above results suggest that Tween can increase arginine production in two ways.
作者
赵越
陈民良
陈雪岚
熊勇华
ZHAO Yue;CHEN Minliang;CHEN Xuelan;XIONG Yonghua(School of Life Science,Jiangxi Normal University,Nanchang 330096,China;Sino German Joint Research Institute,Nanchang University,Nanchang 330047,China)
出处
《食品科学》
EI
CAS
CSCD
北大核心
2022年第2期77-82,共6页
Food Science
基金
国家自然科学基金地区科学基金项目(31960014)
江西省自然科学基金重点项目(20020ACBL205001)。
