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Zhang W, Yang Q, Wu M, Liu H, Zhou J, Dong W, Ma J, Jiang M, Xin F. Metabolic Regulation of Organic Acid Biosynthesis in Actinobacillus succinogenes. Front Bioeng Biotechnol 2019; 7:216. [PMID: 31620431 PMCID: PMC6759810 DOI: 10.3389/fbioe.2019.00216] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 08/27/2019] [Indexed: 11/13/2022] Open
Abstract
Actinobacillus succinogenes is one of the most promising strains for succinic acid production; however, the lack of efficient genetic tools for strain modification development hinders its further application. In this study, a markerless knockout method for A. succinogenes using in-frame deletion was first developed. The resulting ΔpflA (encode pyruvate formate lyase 1-activating protein) strain displayed distinctive organic acid synthesis capacity under different cultivation modes. Additional acetate accumulation was observed in the ΔpflA strain relative to that of the wild type under aerobic conditions, indicating that acetate biosynthetic pathway was activated. Importantly, pyruvate was completely converted to lactate under anaerobic fermentation. The transcription analysis and enzyme assay revealed that the expression level and specific activity of lactate dehydrogenase (LDH) were significantly increased. In addition, the mRNA expression level of ldh was nearly increased 85-fold compared to that of the wild-type strain during aerobic-anaerobic dual-phase fermentation, resulting in 43.05 g/L lactate. These results demonstrate that pflA plays an important role in the regulation of C3 flux distribution. The deletion of pflA leads to the improvement of acetic acid production under aerobic conditions and activates lactic acid biosynthesis under anaerobic conditions. This study will help elaborate the mechanism governing organic acid biosynthesis in A. succinogenes.
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Affiliation(s)
- Wenming Zhang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, China
| | - Qiao Yang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Min Wu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Haojie Liu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Jie Zhou
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China
| | - Weiliang Dong
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, China
| | - Jiangfeng Ma
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, China
| | - Min Jiang
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, China
| | - Fengxue Xin
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, China.,Jiangsu National Synergetic Innovation Center for Advanced Materials, Nanjing Tech University, Nanjing, China
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