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Cheng YY, Park TH, Seong H, Kim TJ, Han NS. Biological characterization of D-lactate dehydrogenase responsible for high-yield production of D-phenyllactic acid in Sporolactobacillus inulinus. Microb Biotechnol 2022; 15:2717-2729. [PMID: 35921426 PMCID: PMC9618312 DOI: 10.1111/1751-7915.14125] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 07/12/2022] [Accepted: 07/21/2022] [Indexed: 01/05/2023] Open
Abstract
PLA (3‐D‐phenyllactic acid) is an ideal antimicrobial and immune regulatory compound present in honey and fermented foods. Sporolactobacillus inulinus is regarded as a potent D‐PLA producer that reduces phenylpyruvate (PPA) with D‐lactate dehydrogenases. In this study, PLA was produced by whole‐cell bioconversion of S. inulinus ATCC 15538. Three genes encoding D‐lactate dehydrogenase (d‐ldh1, d‐ldh2, and d‐ldh3) were cloned and expressed in Escherichia coli BL21 (DE3), and their biochemical and structural properties were characterized. Consequently, a high concentration of pure D‐PLA (47 mM) was produced with a high conversion yield of 88%. Among the three enzymes, D‐LDH1 was responsible for the efficient conversion of PPA to PLA with kinetic parameters of Km (0.36 mM), kcat (481.10 s−1), and kcat/Km (1336.39 mM−1 s−1). In silico structural analysis and site‐directed mutagenesis revealed that the Ile307 in D‐LDH1 is a key residue for excellent PPA reduction with low steric hindrance at the substrate entrance. This study highlights that S. inulinus ATCC 15538 is an excellent PLA producer, equipped with a highly specific and efficient D‐LDH1 enzyme.
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Affiliation(s)
- Ya-Yun Cheng
- Brain Korea 21 Center for Bio-Health Industry, Development, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Korea
| | - Tae Hyeon Park
- Brain Korea 21 Center for Bio-Health Industry, Development, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Korea
| | - Hyunbin Seong
- Brain Korea 21 Center for Bio-Health Industry, Development, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Korea
| | - Tae-Jip Kim
- Brain Korea 21 Center for Bio-Health Industry, Development, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Korea
| | - Nam Soo Han
- Brain Korea 21 Center for Bio-Health Industry, Development, Division of Animal, Horticultural, and Food Sciences, Chungbuk National University, Cheongju, Korea
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2
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Zhang D, Zhang T, Lei Y, Lin W, Chen X, Wu M. Enantioselective Biosynthesis of L-Phenyllactic Acid From Phenylpyruvic Acid In Vitro by L-Lactate Dehydrogenase Coupling With Glucose Dehydrogenase. Front Bioeng Biotechnol 2022; 10:846489. [PMID: 35252153 PMCID: PMC8894805 DOI: 10.3389/fbioe.2022.846489] [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: 12/31/2021] [Accepted: 01/18/2022] [Indexed: 11/13/2022] Open
Abstract
As a valuable versatile building block, L-phenyllactic acid (L-PLA) has numerous applications in the fields of agriculture, pharmaceuticals, and biodegradable plastics. However, both normally chemically synthesized and naturally occurring PLA are racemic, and the production titer of L-PLA is not satisfactory. To improve L-PLA production and reduce the high cost of NADH, an in vitro coenzyme regeneration system of NADH was achieved using the glucose dehydrogenase variant LsGDHD255C and introduced into the L-PLA production process. Here an NADH-dependent L-lactate dehydrogenase-encoding variant gene (L-Lcldh1Q88A/I229A) was expressed in Pichia pastoris GS115. The specific activity of L-LcLDH1Q88A/I229A (Pp) was as high as 447.6 U/mg at the optimum temperature and pH of 40°C and 5.0, which was 38.26-fold higher than that of wild-type L-LcLDH1 (Pp). The catalytic efficiency (kcat/Km) of L-LcLDH1Q88A/I229A (Pp) was 94.3 mM−1 s−1, which was 67.4- and 25.5-fold higher than that of L-LcLDH1(Pp) and L-LcLDH1Q88A/I229A (Ec) expressed in Escherichia coli, respectively. Optimum reactions of L-PLA production by dual-enzyme catalysis were at 40°C and pH 5.0 with 10.0 U/ml L-LcLDH1Q88A/I229A (Pp) and 4.0 U/ml LsGDHD255C. Using 0.1 mM NAD+, 400 mM (65.66 g/L) phenylpyruvic acid was completely hydrolyzed by fed-batch process within 6 h, affording L-PLA with 90.0% yield and over 99.9% eep. This work would be a promising technical strategy for the preparation of L-PLA at an industrial scale.
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Affiliation(s)
- Dong Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Ting Zhang
- Haiyan Food and Drug Inspection and Testing Center, Haiyan, China
| | - Yuqing Lei
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Wenqian Lin
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xingyi Chen
- Wuxi School of Medicine, Jiangnan University, Wuxi, China
| | - Minchen Wu
- Wuxi School of Medicine, Jiangnan University, Wuxi, China
- *Correspondence: Minchen Wu,
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3
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Xu JJ, Sun JZ, Si KL, Guo CF. 3-Phenyllactic acid production by Lactobacillus crustorum strains isolated from naturally fermented vegetables. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.111780] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Lee W, Park YT, Lim S, Yeom SH, Jeon C, Lee HS, Yeon YJ. Efficient Production of Phenyllactic Acid by Whole-cell Biocatalysis with Cofactor Regeneration System. BIOTECHNOL BIOPROC E 2021. [DOI: 10.1007/s12257-020-0270-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Zhang D, Zhu X, Hu D, Wen Z, Zhang C, Wu M. Improvement in the catalytic performance of a phenylpyruvate reductase from Lactobacillus plantarum by site-directed and saturation mutagenesis based on the computer-aided design. 3 Biotech 2021; 11:69. [PMID: 33489686 DOI: 10.1007/s13205-020-02633-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 12/28/2020] [Indexed: 01/02/2023] Open
Abstract
To enhance the specific activity and catalytic efficiency (k cat/K m) of an NADH-dependent LpPPR, its directed modification was performed based on the computer-aided design using molecular docking simulation and multiple sequence alignment. Firstly, five single-site variants of an LpPPR-encoding gene (lpppr) were amplified and expressed in E. coli BL21 (DE3). The asymmetric reduction of 20 mM phenylpyruvic acid (PPA) was carried out using 50 mg/mL E. coli/lpppr R53Q or /lpppr A79V whole wet cells at 37 °C for 20 min, giving d-phenyllactic acid (PLA) with 41.1 or 44.3% yield, being 1.17- or 1.26-fold that by E. coli/lpppr. Secondly, double-site variants were obtained by saturation mutagenesis of Ala79 in LpPPRR53Q. Among all tested E. coli transformants, E. coli/lpppr R53Q/A79V exhibited the highest d-PLA yield of 85.3%. The specific activity and k cat/K m of the purified LpPPRR53Q/A79V increased to 67.5 U/mg and 169.8 mM-1 s-1, which were 3.0- and 13.2-fold those of LpPPR, respectively. Finally, the catalytic mechanism analysis of LpPPRR53Q/A79V by molecular docking simulation indicated that the replacement of Arg53 in LpPPR with Gln expanded its substrate-binding pocket, while that Ala79 with Val formed an additional π-sigma interaction with phenyl group of PPA. SUPPLEMENTARY MATERIAL The online version of this article (10.1007/s13205-020-02633-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Dong Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122 China
| | - Xiuxiu Zhu
- School of Pharmaceutical Science, Jiangnan University, Wuxi, 214122 China
| | - Die Hu
- Wuxi School of Medicine, Jiangnan University, Wuxi, 214122 China
| | - Zheng Wen
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122 China
| | - Chen Zhang
- School of Pharmaceutical Science, Jiangnan University, Wuxi, 214122 China
| | - Minchen Wu
- Wuxi School of Medicine, Jiangnan University, Wuxi, 214122 China
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Luo X, Zhang Y, Yin F, Hu G, Jia Q, Yao C, Fu Y. Enzymological characterization of a novel d-lactate dehydrogenase from Lactobacillus rossiae and its application in d-phenyllactic acid synthesis. 3 Biotech 2020; 10:101. [PMID: 32099742 DOI: 10.1007/s13205-020-2098-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Accepted: 01/24/2020] [Indexed: 12/28/2022] Open
Abstract
A novel lactate dehydrogenase gene, named lrldh, was cloned from Lactobacillus rossiae and heterologously expressed in Escherichia coli. The lactate dehydrogenase LrLDH is NADH-dependent with a molecular weight of approximately 39 kDa. It is active at 40 °C and pH 6.5 and stable in a neutral to alkaline environment below 35 °C. The kinetic constants, including maximal reaction rate (V max), apparent Michaelis-Menten constant (K m), turnover number (K cat) and catalytic efficiency (K cat/K m) for phenylpyruvic acid were 1.95 U mg-1, 2.83 mM, 12.29 s-1, and 4.34 mM-1 s-1, respectively. Using whole cells of recombinant E. coli/pET28a-lrldh, without coexpression of a cofactor regeneration system, 20.5 g l-1 d-phenyllactic acid with ee above 99% was produced from phenylpyruvic acid in a fed-batch biotransformation process, with a productivity of 49.2 g l-1 d-1. Moreover, LrLDH has broad substrate specificity to a range of ketones, keto acids and ketonic esters. Taken together, LrLDH is a promising biocatalyst for the efficient synthesis of d-phenyllactic acid and other fine chemicals.
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Affiliation(s)
- Xi Luo
- 1Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People's Republic of China
| | - Yingying Zhang
- 1Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People's Republic of China
| | - Fengwei Yin
- 1Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People's Republic of China
| | - Gaowei Hu
- 1Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People's Republic of China
| | - Qiang Jia
- Seasons Biotechnology (Taizhou) Co., Ltd, Taizhou, 318000 Zhejiang People's Republic of China
| | - Changsheng Yao
- 3Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials, School of Chemistry and Chemical Engineering, Jiangsu Normal University, Xuzhou, 221116 Jiangsu People's Republic of China
| | - Yongqian Fu
- 1Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People's Republic of China
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7
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Xu JJ, Fu LJ, Si KL, Yue TL, Guo CF. 3-phenyllactic acid production by free-whole-cells of Lactobacillus crustorum in batch and continuous fermentation systems. J Appl Microbiol 2020; 129:335-344. [PMID: 32009287 DOI: 10.1111/jam.14599] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 01/06/2020] [Accepted: 01/29/2020] [Indexed: 01/11/2023]
Abstract
AIM 3-Phenyllactic acid (3-PLA) has been widely used in food and material industries. Three Lactobacillus crustorum strains have shown greater 3-PLA production ability in our previous study. The objectives of this study were to further improve 3-PLA yields in batch and continuous fermentation systems using of free-whole-cells of the three L. crustorum strains. MATERIALS AND RESULTS The fermentation conditions of free-whole-cells of the three L. crustorum strains for 3-PLA production were optimized. Among these strains, L. crustorum NWAFU 1078 showed excellent reusability and significantly (P < 0·05) greater 3-PLA production ability than the other strains after 10th recycle. The strain possesses three l-lactate dehydrogenase and three d-lactate dehydrogenase catalysing 3-PLA production from phenylpyruvic acid (PPA). Under the optimal conditions, the strain produced 15·2 mmol l-1 3-PLA (76% PPA conversion rate) in a batch fermentation system and 6·5 mmol l-1 h-1 3-PLA (55% PPA conversion rate) in a continuous fermentation system using a 0·6 dilution rate. CONCLUSIONS Free-whole-cells of L. crustorum NWAFU 1078 showed excellent reusability and higher 3-PLA yields under optimal biotransformation conditions in both batch and continuous fermentation systems. SIGNIFICANCE AND IMPACT OF THE STUDY This study provides the possibility to use the free-whole-cells of L. crustorum NWAFU 1078 as a biocatalyst for effective production of 3-PLA.
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Affiliation(s)
- J-J Xu
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - L-J Fu
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - K-L Si
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - T-L Yue
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - C-F Guo
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
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Luo X, Zhang Y, Yin L, Zheng W, Fu Y. Efficient synthesis of d-phenyllactic acid by a whole-cell biocatalyst co-expressing glucose dehydrogenase and a novel d-lactate dehydrogenase from Lactobacillus rossiae. 3 Biotech 2020; 10:14. [PMID: 31879578 PMCID: PMC6904706 DOI: 10.1007/s13205-019-2003-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 12/02/2019] [Indexed: 12/11/2022] Open
Abstract
d-Phenyllactic acid is a versatile natural organic acid, which is used as an antiseptic agent, monomer of the biodegradable material poly-phenyllactic acid and in the synthesis chiral intermediate of pharmaceuticals. In this report, the novel NADH-dependent d-lactate dehydrogenase LrLDH was identified by screening a shotgun genome of Lactobacillus rossiae. To improve cofactor regeneration, the Exiguobacterium sibiricum glucose dehydrogenase EsGDH was overexpressed together with LrLDH in E. coli BL21(DE3)-pCDFDuet-1-gdh-ldh. The total enzyme activity in the fermentation broth of E. coli BL 21(DE3)-pCDFDuet-1-gdh-ldh peaked at 2359.0 U l-1 when induced by 10 g l-1 lactose at 28 °C and 150 rpm for 14 h. The biocatalytic reduction of sodium phenylpyruvate to d-phenyllactic acid was successfully carried out using whole cells of the engineered E. coli. Under the optimized biocatalysis conditions, 50 g l-1 sodium phenylpyruvate was completely converted to d-phenyllactic acid with a space-time yield and enantiomeric excess of 262.8 g l-1 day-1 and > 99.5%, respectively. To our best knowledge, it is the highest productivity reported to date, with great potential for the mass production of d-phenyllactic acid.
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Affiliation(s)
- Xi Luo
- Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People’s Republic of China
| | - Yingying Zhang
- Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People’s Republic of China
| | - Longfei Yin
- Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People’s Republic of China
| | - Weilong Zheng
- Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People’s Republic of China
| | - Yongqian Fu
- Institute of Biomass Resources, Taizhou University, Taizhou, 318000 Zhejiang People’s Republic of China
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9
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Lee HS, Park J, Yoo YJ, Yeon YJ. Engineering D-Lactate Dehydrogenase from Pediococcus acidilactici for Improved Activity on 2-Hydroxy Acids with Bulky C 3 Functional Group. Appl Biochem Biotechnol 2019; 189:1141-1155. [PMID: 31190286 DOI: 10.1007/s12010-019-03053-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 05/22/2019] [Indexed: 11/30/2022]
Abstract
Engineering D-lactic acid dehydrogenases for higher activity on various 2-oxo acids is important for the synthesis of 2-hydroxy acids that can be utilized in a wide range of industrial fields including the production of biopolymers, pharmaceuticals, and cosmetic compounds. Although there are many D-lactate dehydrogenases (D-LDH) available from a diverse range of sources, there is a lack of biocatalysts with high activities for 2-oxo acids with large functional group at C3. In this study, the D-LDH from Pediococcus acidilactici was rationally designed and further engineered by controlling the intermolecular interactions between substrates and the surrounding residues via analysis of the active site structure of D-LDH. As a result, Y51L mutant with the catalytic efficiency on phenylpyruvate of 2200 s-1 mM-1 and Y51F mutant on 2-oxobutryate and 3-methyl-2-oxobutyrate of 37.2 and 23.2 s-1 mM-1 were found, which were 138-, 8.5-, and 26-fold increases than the wild type on the substrates, respectively. Structural analysis revealed that the distance and the nature of the interactions between the side chain of residue 51 and the substrate C3 substituent group significantly affected the kinetic parameters. Bioconversion of phenyllactate as a practical example of production of the 2-hydroxy acids was investigated, and the Y51F mutant presented the highest productivity in in vitro conversion of D-PLA.
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Affiliation(s)
- Hoe-Suk Lee
- Program of Bioengineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jisu Park
- Department of Biochemical Engineering, Gangneung-Wonju National University, 7, Jukheon-gil, Gangneung-si, Gangwon-do, 25457, Republic of Korea
| | - Young Je Yoo
- Program of Bioengineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea. .,School of Chemical and Biological Engineering, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
| | - Young Joo Yeon
- Department of Biochemical Engineering, Gangneung-Wonju National University, 7, Jukheon-gil, Gangneung-si, Gangwon-do, 25457, Republic of Korea.
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Lee HS, Park J, Yoo YJ, Yeon YJ. A novel d-2-hydroxy acid dehydrogenase with high substrate preference for phenylpyruvate originating from lactic acid bacteria: Structural analysis on the substrate specificity. Enzyme Microb Technol 2019; 125:37-44. [DOI: 10.1016/j.enzmictec.2019.02.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 02/15/2019] [Accepted: 02/22/2019] [Indexed: 10/27/2022]
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Zhou X, Zhou J, Xin F, Ma J, Zhang W, Wu H, Jiang M, Dong W. Heterologous expression of a novel d‑lactate dehydrogenase from Lactobacillus sp. ZX1 and its application for d‑phenyllactic acid production. Int J Biol Macromol 2018; 119:1171-1178. [DOI: 10.1016/j.ijbiomac.2018.08.036] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 08/07/2018] [Accepted: 08/08/2018] [Indexed: 01/07/2023]
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Zhu YB, Xu Y, Wang LM, Qi B. Biosynthesis of (R)-2-hydroxy-3-phenylpropionic acid using whole recombinant Escherichia coli cells in an aqueous/n-octane biphasic system. J Zhejiang Univ Sci B 2018; 19:285-292. [PMID: 29616504 DOI: 10.1631/jzus.b1700040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
(R)-2-hydroxy-3-phenylpropionic acid (PLA) is an ideal antimicrobial compound with broad-spectrum activity against a wide range of Gram-positive bacteria, some Gram-negative bacteria, and fungi. We studied the bioconversion of phenylpyruvate (PPA) to PLA using whole recombinant Escherichia coli cells in a series of buffer/organic solvent systems. Octane was found to be the best organic solvent. The optimum volume ratio of the water phase to the n-octane phase, conversion temperature, substrate concentration, and cell concentration were 6:4, 40 °C, 12.5 g/L, and 30 g/L wet cells, respectively. Under the optimized conditions, the average PLA productivity in the aqueous/ n-octane system was 30.69% higher than that in the aqueous system, and 32.31 g/L PLA was obtained with the use of a stirred reactor (2-L scale). Taken together, our findings indicated that PLA biosynthesis was more efficient in an aqueous/n-octane biphasic system than in a monophasic aqueous system. The proposed biphasic system is an effective strategy for enhancing PLA yield and the biosynthesis of its analogues.
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Affiliation(s)
- Yi-Bo Zhu
- Key Laboratory of Food and Biotechnology of Suzhou, Changshu Institute of Technology, Changshu 215500, China
| | - Yan Xu
- Key Laboratory of Food and Biotechnology of Suzhou, Changshu Institute of Technology, Changshu 215500, China.,Institute of Basic Medical and Biological Sciences, Soochow University, Suzhou 215000, China
| | - Li-Mei Wang
- Key Laboratory of Food and Biotechnology of Suzhou, Changshu Institute of Technology, Changshu 215500, China
| | - Bin Qi
- Key Laboratory of Food and Biotechnology of Suzhou, Changshu Institute of Technology, Changshu 215500, China
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13
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Wang YH, Bai YJ, Fan TP, Zheng XH, Cai YJ. Reducing 3,4-dihydroxyphenylpyruvic acid to d-3,4-dihydroxyphenyllactic acid via a coenzyme nonspecific d-lactate dehydrogenase from Lactobacillus reuteri. J Appl Microbiol 2018; 125:1739-1748. [PMID: 30129993 DOI: 10.1111/jam.14077] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Revised: 08/07/2018] [Accepted: 08/11/2018] [Indexed: 01/11/2023]
Abstract
AIMS The purpose of this work was to find an efficient enzyme to synthesize d-3,4-dihydroxyphenyllactic acid (d-DSS). METHODS AND RESULTS Nineteen lactic acid bacteria strains were screened for production of d-DSS using 3,4-dihydroxyphenylpyruvic acid (DPA) as a substrate. Lactobacillus reuteri JN516 exhibited the highest d-DSS yield. A nonspecific coenzyme, d-lactate dehydrogenase (d-LDH82319), from L. reuteri JN516 with high DPA reducing activity was identified. This enzyme reduced DPA to form d-DSS with excellent optical purity (enantioselectivity >99%). Its molecular weight was 35 kDa based on SDS-PAGE migration. The Michaelis-Menten constant (Km ), turnover number (kcat ), and catalytic efficiency (kcat /Km ) of d-LDH82319 for DPA were 0·09 mmol l-1 , 2·17 s-1 and 24·07 (mmol l-1 )-1 s-1 , respectively, with NADH as the coenzyme. The (Km ), (kcat ) and (kcat /Km ) of d-LDH82319 for DPA were 0·10 mmol l-1 , 0·13 s-1 and 1·30 (mmol l-1 )-1 s-1 , respectively, with NADPH as the coenzyme. The optimum temperature and pH of d-LDH82319 were 25°C and pH 8 respectively. Additionally, d-LDH82319 had a broad substrate range for alpha-keto acids, among which the activity of reducing pyruvate was the strongest; therefore, it belongs to the group of d-lactate dehydrogenases. d-LDH82319 and glucose dehydrogenase (GDH) were coexpressed to produce d-DSS from DPA. CONCLUSIONS d-LDH82319 from L. reuteri JN516 with high DPA reducing activity has the characteristics of a nonspecific coenzyme. SIGNIFICANCE AND IMPACT OF THE STUDY d-LDH82319 is the first reported coenzyme nonspecific d-lactate dehydrogenase with DPA-reducing activity. The coexpression system provided an effective method to produce d-DSS.
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Affiliation(s)
- Y H Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Y J Bai
- College of Life Sciences, Northwest University, Xi'an, China
| | - T-P Fan
- College of Life Sciences, Northwest University, Xi'an, China
- Department of Pharmacology, University of Cambridge, Cambridge, UK
| | - X H Zheng
- College of Life Sciences, Northwest University, Xi'an, China
| | - Y J Cai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
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14
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Contributory roles of two l-lactate dehydrogenases for l-lactic acid production in thermotolerant Bacillus coagulans. Sci Rep 2016; 6:37916. [PMID: 27885267 PMCID: PMC5122838 DOI: 10.1038/srep37916] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 11/04/2016] [Indexed: 02/06/2023] Open
Abstract
Thermotolerant Bacillus coagulans is considered to be a more promising producer for bio-chemicals, due to its capacity to withstand harsh conditions. Two L-lactate dehydrogenase (LDH) encoding genes (ldhL1 and ldhL2) and one D-LDH encoding gene (ldhD) were annotated from the B. coagulans DSM1 genome. Transcriptional analysis revealed that the expression of ldhL2 was undetectable while the ldhL1 transcription level was much higher than that of ldhD at all growth phases. Deletion of the ldhL2 gene revealed no difference in fermentation profile compared to the wild-type strain, while ldhL1 single deletion or ldhL1ldhL2 double deletion completely blocked L-lactic acid production. Complementation of ldhL1 in the above knockout strains restored fermentation profiles to those observed in the wild-type strain. This study demonstrates ldhL1 is crucial for L-lactic acid production and NADH balance in B. coagulans DSM1 and lays the fundamental for engineering the thermotolerant B. coagulans strain as a platform chemicals producer.
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