巢湖学院学报 ›› 2021, Vol. 23 ›› Issue (6): 85-92.doi: 10.12152/j.issn.1672-2868.2021.06.012

• 生命与环境科学 • 上一篇    下一篇

钝齿棒杆菌乳酸脱氢酶基因敲除菌株的构建

陈小举,蒋慧慧,刘万逛:巢湖学院 化学与材料工程学院   

  1. 巢湖学院 化学与材料工程学院,安徽 巢湖 238024
  • 收稿日期:2021-10-09 出版日期:2021-11-25 发布日期:2022-03-07
  • 作者简介:陈小举(1984—),男,安徽砀山人,巢湖学院化学与材料工程学院副教授,博士,主要从事有机酸发酵、生物资源综合利用研究。
  • 基金资助:
    安徽省自然科学基金项目(项目编号:1908085QC123);安徽省高校学科(专业)拔尖人才学术资助项目(项目编号:gxbjZD37)

Knockout of the Lactate Dehydrogenase Gene of Corynebacterium Crenatum

CHEN Xiao-ju, JIANG Hui-hui, LIU Wan-guang: School of Chemistry and Material Engineering, Chaohu University   

  1. School of Chemistry and Material Engineering, Chaohu University, Chaohu Anhui 238024
  • Received:2021-10-09 Online:2021-11-25 Published:2022-03-07

摘要: 目的 钝齿棒杆菌厌氧发酵时,其主要代谢产物为琥珀酸和乳酸。敲除乳酸脱氢酶基因(LdhA)可以减少乳酸的生成,提高钝齿棒杆菌产琥珀酸代谢途径的通量。方法 为获得乳酸脱氢酶基因缺失的钝齿棒杆菌突变株,先通过PCR扩增获得LdhA基因的上、下游同源重组臂及卡那霉素抗性基因(Kn),然后通过融合PCR技术将LdhA基因上、下游同源重组臂与Kn抗性基因连接构建打靶片断与打靶质粒。结果 先后成功构建了打靶片段?LdhA::Kn、打靶质质粒pCVD442-?LdhA::Kn与供体菌株E.coli β2155/pCVD442-?LdhA::Kn,并成功筛选到具有卡那霉素抗性的钝齿棒杆菌单克隆菌株。结论 PCR鉴定与乳酸脱氢酶活力分析结果表明,钝齿棒杆菌基因组中LdhA基因被Kn抗性基因替换,LdhA基因敲除成功,为后续利用钝齿棒杆菌高产琥珀酸奠定了基础。

关键词: 钝齿棒杆菌, 乳酸脱氢酶, 基因敲除, 融合PCR技术

Abstract: [Objective] Succinic acid and lactic acid are the main products when Corynebacterium crenatum were cultured under anaerobic conditions. The knockout of lactate dehydrogenase gene(LdhA), a key enzyme for lactic acid production, can decrease the production of lactic acid and increase the flux of the metabolic pathway for succinic acid production. [Methods] In order to obtain the C. crenatum ?LdhA mutant strain, the upstream and downstream homologous recombination genes of LdhA and kanamycin resistance gene (Kn) were obtained by PCR. Afterwards, the targeting homologue recombination DNA and plasmid were constructed by fusion PCR. [Results] The targeting homologue recombination DNA of ?LdhA::Kn, targeting plasmid of pCVD442-?LdhA::Kn and donor bacteria of E.coli β2155/pCVD442-?LdhA::Kn were constructed, and the mutant strain of C. crenatum which had resistance to kanamycin was screened. [Conclusion] The results of PCR and lactate dehydrogenase activity analysis indicated that the LdhA in genome of C. crenatum was knockout and replaced by Kn. This study provides a foundation for producing succinic acid efficiently using C. crenatum.

Key words: Corynebacterium crenatum, lactate dehydrogenase, gene knockout, fusion PCR technology

中图分类号: 

  • Q789