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Eliminating host-guest incompatibility via enzyme mining enables the high-temperature production of N-acetylglucosamine. iScience 2022; 26:105774. [PMID: 36636338 PMCID: PMC9829697 DOI: 10.1016/j.isci.2022.105774] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 10/09/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
The host-guest incompatibility between a production host and non-native enzymes has posed an arduous challenge for synthetic biology, particularly between mesophile-derived enzymes and a thermophilic chassis. In the present study, we develop a thermophilic enzyme mining strategy comprising an automated co-evolution-based screening pipeline (http://cem.sjtu.edu.cn), computation-based enzyme characterization, and gene synthesis-based function validation. Using glucosamine-6-phosphate acetyltransferase (GNA1) as an example, we successfully mined four novel GNA1s with excellent thermostabilities and catalytic performances. Calculation and analysis based on AlphaFold2-generated structures were also conducted to uncover the mechanism underlying their excellent properties. Finally, our mined GNA1s were used to enable the high-temperature N-acetylglucosamine (GlcNAc) production with high titers of up to 119.3 g/L, with the aid of systems metabolic engineering and temperature programming. This study demonstrates the effectiveness of the enzyme mining strategy, highlighting the application prospects of mining new enzymes from massive databases and providing an effective solution for tackling host-guest incompatibility.
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Establishment of a salt-induced bioremediation platform from marine Vibrio natriegens. Commun Biol 2022; 5:1352. [PMID: 36494435 PMCID: PMC9734156 DOI: 10.1038/s42003-022-04319-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 11/29/2022] [Indexed: 12/13/2022] Open
Abstract
Industrial wastewater discharge, agricultural production, marine shipping, oil extraction, and other activities have caused serious marine pollution, including microplastics, petroleum and its products, heavy metals, pesticides, and other organics. Efficiency of bioremediation of marine pollutions may be limited by high salt concentrations (>1%, w/v), which can cause an apparent loss of microbial activities. In this study, functional promoters P1, P2-1, and P2-2 censoring salt stress were isolated and identified from a Vibrio natriegens strain Vmax. Three salt-induced degradation models were constructed to degrade polyethylene terephthalate (PET), chlorpyrifos (CP), and hexabromocyclododecanes (HBCDs) using the marine strain Vmax. The engineered strains are efficient for degradation of the corresponding substrates, with the degradation rates at 15 mg/L PET in 8 d, 50 mg/L CP in 24 h, and 1 mg/L HBCDs in 4 h, respectively. In addition, an immobilization strategy for recycling and reusing of engineered strains was realized by expressing the chitin-binding protein GbpA. This study may help answer the usage of rapidly growing marine bacteria such as V. natriegens Vmax to degrade marine pollution efficiently.
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Wang X, Zhang L, Liang S, Yin Y, Wang P, Li Y, Chin WS, Xu J, Wen J. Enhancing the capability of Klebsiella pneumoniae to produce 1, 3-propanediol by overexpression and regulation through CRISPR-dCas9. Microb Biotechnol 2022; 15:2112-2125. [PMID: 35298861 PMCID: PMC9249332 DOI: 10.1111/1751-7915.14033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 03/06/2022] [Indexed: 11/30/2022] Open
Abstract
Klebsiella pneumoniae is a common strain of bacterial fermentation to produce 1, 3‐propanediol (1, 3‐PDO). In general, the production of 1, 3‐PDO by wild‐type K. pneumoniae is relatively low. Therefore, a new gene manipulation of K. pneumoniae was developed to improve the production of 1, 3‐PDO by overexpressing in the reduction pathway and attenuating the by‐products in the oxidation pathway. Firstly, dhaB and/or dhaT were overexpressed in the reduction pathway. Considering the cost of IPTG, the constitutive promoter P32 was selected to express the key gene. By comparing K.P. pET28a‐P32‐dhaT with the original strain, the production of 1, 3‐PDO was increased by 19.7%, from 12.97 to 15.53 g l−1 (in a 250 ml shaker flask). Secondly, three lldD and budC regulatory sites were selected in the by‐product pathway, respectively, using the CRISPR‐dCas9 system, and the optimal regulatory sites were selected following the 1, 3‐PDO production. As a result, the 1, 3‐PDO production by K.P. L1‐pRH2521 and K.P. B3‐pRH2521 reached up to 19.16 and 18.74 g l−1, which was increased by 47.7% and 44.5% respectively. Overexpressing dhaT and inhibiting expression of lldD and budC were combined to further enhance the ability of K. pneumoniae to produce 1, 3‐PDO. The 1, 3‐PDO production by K.P. L1‐B3‐PRH2521‐P32‐dhaT reached 57.85 g l−1 in a 7.5 l fermentation tank (with Na+ neutralizer), which is higher than that of the original strain. This is the first time that the 1, 3‐PDO production was improved in K. pneumoniae by overexpressing the key gene and attenuating by‐product synthesis in the CRISPR‐dCas9 system. This study reports an efficient approach to regulate the expression of genes in K. pneumoniae to increase the 1, 3‐PDO production, and such a strategy may be useful to modify other strains to produce valuable chemicals.
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Affiliation(s)
- Xin Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China.,Institute of Materials Research and Engineering, Agency for Science, Technology and Research, #08-03, 2 Fusionopolis Way, Singapore, 138634, Singapore.,Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Lin Zhang
- Dalian Petrochemical Research Institute of Sinopec, Dalian, 116000, China
| | - Shaoxiong Liang
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Ying Yin
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Pan Wang
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Yicao Li
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
| | - Wee Shong Chin
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Jianwei Xu
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, #08-03, 2 Fusionopolis Way, Singapore, 138634, Singapore.,Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Jianping Wen
- Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin, 300072, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300072, China
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Cui J, Sun T, Chen L, Zhang W. Salt-Tolerant Synechococcus elongatus UTEX 2973 Obtained via Engineering of Heterologous Synthesis of Compatible Solute Glucosylglycerol. Front Microbiol 2021; 12:650217. [PMID: 34084156 PMCID: PMC8168540 DOI: 10.3389/fmicb.2021.650217] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/25/2021] [Indexed: 01/08/2023] Open
Abstract
The recently isolated cyanobacterium Synechococcus elongatus UTEX 2973 (Syn2973) is characterized by a faster growth rate and greater tolerance to high temperature and high light, making it a good candidate chassis for autotrophic photosynthetic microbial cell factories. However, Syn2973 is sensitive to salt stress, making it urgently important to improve the salt tolerance of Syn2973 for future biotechnological applications. Glucosylglycerol, a compatible solute, plays an important role in resisting salt stress in moderate and marine halotolerant cyanobacteria. In this study, the salt tolerance of Syn2973 was successfully improved by introducing the glucosylglycerol (GG) biosynthetic pathway (OD750 improved by 24% at 60 h). In addition, the salt tolerance of Syn2973 was further enhanced by overexpressing the rate-limiting step of glycerol-3-phosphate dehydrogenase and downregulating the gene rfbA, which encodes UDP glucose pyrophosphorylase. Taken together, these results indicate that the growth of the end-point strain M-2522-GgpPS-drfbA was improved by 62% compared with the control strain M-pSI-pSII at 60 h under treatment with 0.5 M NaCl. Finally, a comparative metabolomic analysis between strains M-pSI-pSII and M-2522-GgpPS-drfbA was performed to characterize the carbon flux in the engineered M-2522-GgpPS-drfbA strain, and the results showed that more carbon flux was redirected from ADP-GLC to GG synthesis. This study provides important engineering strategies to improve salt tolerance and GG production in Syn2973 in the future.
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Affiliation(s)
- Jinyu Cui
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
| | - Tao Sun
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Tianjin University, Tianjin, China.,Center for Biosafety Research and Strategy, Tianjin University, Tianjin, China
| | - Lei Chen
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China
| | - Weiwen Zhang
- Laboratory of Synthetic Microbiology, School of Chemical Engineering & Technology, Tianjin University, Tianjin, China.,Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering, Tianjin University, Tianjin, China.,SynBio Research Platform, Collaborative Innovation Center of Chemical Science and Engineering, Tianjin, China.,Center for Biosafety Research and Strategy, Tianjin University, Tianjin, China
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