过表达乙酰-CoA相关基因提高出芽短梗霉liamocins合成能力  

Overexpression of acetyl-CoA synthase and relative enzymes enhanced liamocins synthesis in Aureobasidium pullulans

作　　者：郑鹏 张孟娟[1,2] 黄思瑶 康新玥 陈叶福 ZHENG Peng;ZHANG Mengjuan;HUANG Siyao;KANG Xinyue;CHEN Yefu(College of Bioengineering,Tianjin University of Science and Technology,Tianjin 300457,China;Key Laboratory of Industrial Fermentation Microbiology,Ministry of Education,Tianjin University of Science and Technology,Tianjin 300457,China)

机构地区：[1]天津科技大学生物工程学院,天津300457 [2]工业发酵微生物教育部重点实验室(天津科技大学),天津300457

出　　处：《食品与发酵工业》2020年第9期25-30,共6页Food and Fermentation Industries

基　　金：工业微生物优良菌种选育与发酵技术公共服务平台(17PTGCCX00190)。

摘　　要：为提高出芽短梗霉liamocins合成能力,分别过表达了出芽短梗霉P30的乙酰-CoA合成相关基因,包括乙酰-CoA合酶编码基因(ACS1)、ATP-依赖性柠檬酸裂解酶编码基因(ACL)、苹果酸酶编码基因(ME)、丙酮酸羧化酶编码基因(PYC1)。重组菌株的liamocins产量分别提高了8.19%、93.74%、13.49%和17.12%,其中过表达ACL的提升效果最为明显,但该基因的转录水平仅提高了0.94倍,这说明ACL为出芽短梗霉P30合成liamocins的关键基因,liamocins合成的能力或许受ACL转录水平的限制。结果表明,强化乙酰-CoA合成可以提高liamocins产量,而其中的ACL基因对其合成至关重要。研究为解决liamocins合成过程中碳代谢流前体不足问题提供了解决思路。To improve liamocins synthesis in Aureobasidium pullulans, acetyl-CoA synthase encoded by ACS1, ATP-dependent citrate lyase(ACL), malate enzyme(ME) and pyruvate carboxylase(PYC1) were overexpressed in Aureobasidium pullulans P30. After overexpression of ACS1, ACL, ME and PYC1, the yield of liamocins increased by 8.19%, 93.74%, 13.49% and 17.12%, respectively. Among them, overexpression of ACL achieved the highest liamocins production(19.44 g/L), even if its transcription level only increased by 94%, indicating that ACL is the key enzyme in liamocins synthesis. Elevation of the ACL transcription level may help for further improving the liamocins’ production. The results indicated that acetyl-CoA synthesis pathway was important for liamocins production. The findings in this study provide a new way for enhancing the synthesis of liamocins by providing sufficient precursors.

关 键 词：liamocins 乙酰-CoA ATP-依赖性柠檬酸裂解酶 出芽短梗霉 代谢工程 

分 类 号：TQ920.1[轻工技术与工程—发酵工程]