Page 128 - 《精细化工》2023年第5期
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第 40 卷第 5 期                             精   细   化   工                                  Vol.40, No.5
             20 23 年 5 月                             FINE CHEMICALS                                 May  2023


              生物工程
                          过量表达甲酸脱氢酶提高大肠杆菌合成


                                           L-2-氨基丁酸的效率



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                      李   莹 ,史红玲            1,2 ,王   喆 ,冉璐妮 ,薛   闯 ,唐存多
                 (1.  南阳师范学院  河南省伏牛山昆虫生物学重点实验室,河南  南阳   473061;2.  大连理工大学  生物工
                 程学院,辽宁  大连  116024)
                 摘要:为了实现 L-2-氨基丁酸(L-ABA)的高效生物合成,借助 pACYCDuet-1 和 pET28a 共表达系统,构建了
                 携带 L-苏氨酸脱氨酶(L-TD)、L-亮氨酸脱氢酶(L-L-DH)和不同活性甲酸脱氢酶(FDH)编码基因的重组大
                 肠杆菌,分别命名为:E. coli BL21 (DE3)/pACYCDuet-1-EcTD-EsLeuDH: pET28a-CbFDH 和 E. coli BL21 (DE3)/
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                 pACYCDuet-1-EcTD-EsLeuDH: pET28a-CbFDH 。经诱导表达后,L-苏氨酸脱氨酶和 L-亮氨酸脱氢酶在两个重
                 组大肠杆菌中的表达水平基本一致,而后者的甲酸脱氢酶酶活表达水平为(342.00±9.40) IU/mL,显著高于前者的
                 (196.00±6.20) IU/mL。在 50 mL 反应体系中,200 mmol/L L-苏氨酸经 220 r/min、30  ℃下反应 6 h 时,前者 L-ABA
                 得率为 71%,后者为 85%。结果表明,提高甲酸脱氢酶的表达水平可以显著提高 L-ABA 的合成效率。此外,
                 优化反应温度后,在 35  ℃下反应 6 h 时,L-ABA 的得率可达 90%。
                 关键词:L-2-氨基丁酸;L-苏氨酸;共表达;微生物细胞工厂;全细胞催化;生物工程
                 中图分类号:TQ922      文献标识码:A      文章编号:1003-5214 (2023) 05-1048-07



                     Increase of L-2-aminobutyric acid yield via formate dehydrogenase
                                        overexpression in Escherichia coli


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                       LI Ying , SHI Hongling , WANG Zhe , RAN Luni , XUE Chuang , TANG Cunduo
                 (1. Henan Provincial Key Laboratory of Funiu Mountain Insect Biology, Nanyang Normal University, Nanyang 473061,
                 Henan, China; 2. School of Bioengineering, Dalian University of Technology, Dalian 116024, Liaoning, China)
                 Abstract:  In order to achieve the efficient biosynthesis of L-2-aminobutyric acid (L-ABA), two
                 recombinant  Escherichia coli strains carrying L-threonine deaminase (L-TD), L-leucine dehydrogenase
                 (L-L-DH) and different formate dehydrogenases (FDH) encoding genes were established by using a dual
                 plasmid co-expression system of pACYCDuet-1  and  pET28a, and  named  E. coli BL21
                 (DE3)/pACYCDuet-1-EcTD-EsLeuDH: pET28a-CbFDH and  E. coli BL21 (DE3)/pACYCDuet-1-EcTD-
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                 EsLeuDH: pET28a-CbFDH , respectively. After induction, the expression levels of L-threonine deaminase
                 and L-leucine dehydrogenase in the two recombinant E. coli strains were basically the same, while that of
                 formate dehydrogenase in the latter was  (342.00±9.40)  IU/mL, significantly higher  than (196.00±6.20)
                 IU/mL expressed in the former strain. In a 50 mL reaction system with 200 mmol/L L-threonine reacted at
                 220 r/min and 30  ℃  for 6 h, the yield of L-ABA was 71% in the former and 85% in the latter. The results
                 showed that formate dehydrogenase overexpression could significantly improve the synthesis efficiency of
                 L-ABA. Moreover, the yield of L-ABA  reached  90%  when catalyzed at 220  r/min and the  optimized
                 temperature of 35  ℃  for 6 h.
                 Key words:  L-2-aminobutyric acid; L-threonine; co-expression; microbial  cell factory; whole cell
                 catalysis; biological engineering



                 收稿日期:2022-08-30;  定用日期:2022-11-08; DOI: 10.13550/j.jxhg.20220812
                 基金项目:国家自然科学基金(31900916);河南省青年人才托举工程项目(2021HYTP036);河南省高校科技创新人才(21HASTIT041)
                 作者简介:李   莹(1997—),女,硕士生,E-mail:2983753362@qq.com。联系人:唐存多(1987—),男,副教授,E-mail:tcd530@126.com。
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