scholarly journals Construction and characterization of a novel glucose dehydrogenase-leucine dehydrogenase fusion enzyme for the biosynthesis of L-tert-leucine

2020 ◽  
Author(s):  
Langxing Liao ◽  
Yonghui Zhang ◽  
Yali Wang ◽  
Yousi Fu ◽  
Aihui Zhang ◽  
...  
Keyword(s):  
Glucose Dehydrogenase ◽  
Catalytic Efficiency ◽  
Space Time ◽  
Cofactor Regeneration ◽  
Enzyme Complex ◽  
Regeneration System ◽  
Regeneration Rate ◽  
Leucine Dehydrogenase ◽  
Fusion Enzyme ◽  
Space Time Yield

Abstract Background: Biosynthesis of L-tert-leucine (L-tle), a significant pharmaceutical intermediate, by a cofactor regeneration system friendly and efficiently is a worthful goal all the time. The cofactor regeneration system of leucine dehydrogenase (LeuDH) and glucose dehydrogenase (GDH) has showed great coupling catalytic efficiency in the synthesis of L-tle, however the multi-enzyme complex of GDH and LeuDH has never been constructed successfully.Results: In this work, a novel fusion enzyme (GDH-R3-LeuDH) for the efficient biosynthesis of L-tle was constructed by the fusion of LeuDH and GDH mediated with a rigid peptide linker. Compared with the free enzymes, both the environmental tolerance and thermal stability of GDH-R3-LeuDH had a great improved since the fusion structure. The fusion structure also accelerated the cofactor regeneration rate and maintained the enzyme activity, so the productivity and yeild of L-tle by GDH-R3-LeuDH was all enhanced by 2-fold. Finally, the space-time yield of L-tle catalyzing by GDH-R3-LeuDH whole cells could achieve 2136 g/L/d in a 200 mL scale system under the optimal catalysis conditions (pH 9.0, 30 °C, 0.4 mM of NAD+ and 500 mM of a substrate including trimethylpyruvic acid and glucose).Conclusions: It is the first report about the fusion of GDH and LeuDH as the multi-enzyme complex to synthesize L-tle and reach the highest space-time yield up to now. These results demonstrated the great potential of the GDH-R3-LeuDH fusion enzyme for the efficient biosynthesis of L-tle.

scholarly journals Construction and characterization of a novel glucose dehydrogenase-leucine dehydrogenase fusion enzyme for the biosynthesis of l-tert-leucine

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Langxing Liao ◽  
Yonghui Zhang ◽  
Yali Wang ◽  
Yousi Fu ◽  
Aihui Zhang ◽  
...  
Keyword(s):  
Glucose Dehydrogenase ◽  
Catalytic Efficiency ◽  
Space Time ◽  
Cofactor Regeneration ◽  
Enzyme Complex ◽  
Regeneration System ◽  
Regeneration Rate ◽  
Leucine Dehydrogenase ◽  
Fusion Enzyme ◽  
Space Time Yield

Abstract Background Biosynthesis of l-tert-leucine (l-tle), a significant pharmaceutical intermediate, by a cofactor regeneration system friendly and efficiently is a worthful goal all the time. The cofactor regeneration system of leucine dehydrogenase (LeuDH) and glucose dehydrogenase (GDH) has showed great coupling catalytic efficiency in the synthesis of l-tle, however the multi-enzyme complex of GDH and LeuDH has never been constructed successfully. Results In this work, a novel fusion enzyme (GDH–R3–LeuDH) for the efficient biosynthesis of l-tle was constructed by the fusion of LeuDH and GDH mediated with a rigid peptide linker. Compared with the free enzymes, both the environmental tolerance and thermal stability of GDH–R3–LeuDH had a great improved since the fusion structure. The fusion structure also accelerated the cofactor regeneration rate and maintained the enzyme activity, so the productivity and yield of l-tle by GDH–R3–LeuDH was all enhanced by twofold. Finally, the space–time yield of l-tle catalyzing by GDH–R3–LeuDH whole cells could achieve 2136 g/L/day in a 200 mL scale system under the optimal catalysis conditions (pH 9.0, 30 °C, 0.4 mM of NAD+ and 500 mM of a substrate including trimethylpyruvic acid and glucose). Conclusions It is the first report about the fusion of GDH and LeuDH as the multi-enzyme complex to synthesize l-tle and reach the highest space–time yield up to now. These results demonstrated the great potential of the GDH–R3–LeuDH fusion enzyme for the efficient biosynthesis of l-tle.

scholarly journals Efficient synthesis of Ibrutinib chiral intermediate in high space-time yield by recombinant E. coli co-expressing alcohol dehydrogenase and glucose dehydrogenase

RSC Advances ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 2325-2331 ◽  
Author(s):  
Yitong Chen ◽  
Baodi Ma ◽  
Songshuang Cao ◽  
Xiaomei Wu ◽  
Yi Xu
Keyword(s):  
Alcohol Dehydrogenase ◽  
Glucose Dehydrogenase ◽  
Space Time ◽  
Optically Active ◽  
Efficient Synthesis ◽  
E Coli ◽  
Efficient Process ◽  
High Space ◽  
Space Time Yield

A simple and efficient process for the synthesis of optically active (S)-N-boc-3-hydroxy piperidine was developed using the “designer cells” co-expressing alcohol dehydrogenase and glucose dehydrogenase.

scholarly journals Structure-guided steric hindrance engineering of Bacillus badius phenylalanine dehydrogenase for efficient l-homophenylalanine synthesis

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Tao Wu ◽  
Xiaoqing Mu ◽  
Yuyan Xue ◽  
Yan Xu ◽  
Yao Nie
Keyword(s):  
Steric Hindrance ◽  
Degrees Of Freedom ◽  
Glucose Dehydrogenase ◽  
Reaction System ◽  
Docking Simulation ◽  
Catalytic Efficiency ◽  
Space Time ◽  
Enzyme Engineering ◽  
Phenylalanine Dehydrogenase ◽  
Phenylbutyric Acid

Abstract Background Direct reductive amination of prochiral 2-oxo-4-phenylbutyric acid (2-OPBA) catalyzed by phenylalanine dehydrogenase (PheDH) is highly attractive in the synthesis of the pharmaceutical chiral building block l-homophenylalanine (l-HPA) given that its sole expense is ammonia and that water is the only byproduct. Current issues in this field include a poor catalytic efficiency and a low substrate loading. Results In this study, we report a structure-guided steric hindrance engineering of PheDH from Bacillus badius to create an enhanced biocatalyst for efficient l-HPA synthesis. Mutagenesis libraries based on molecular docking, double-proximity filtering, and a degenerate codon significantly increased catalytic efficiency. Seven superior mutants were acquired, and the optimal triple-site mutant, V309G/L306V/V144G, showed a 12.7-fold higher kcat value, and accordingly a 12.9-fold higher kcat/Km value, than that of the wild type. A paired reaction system comprising V309G/L306V/V144G and glucose dehydrogenase converted 1.08 M 2-OPBA to l-HPA in 210 min, and the specific space–time conversion was 30.9 mmol g−1 L−1 h−1. The substrate loading and specific space–time conversion are the highest values to date. Docking simulation revealed increases in substrate-binding volume and additional degrees of freedom of the substrate 2-OPBA in the pocket. Tunnel analysis suggested the formation of new enzyme tunnels and the expansion of existing ones. Conclusions Overall, the results show that the mutant V309G/L306V/V144G has the potential for the industrial synthesis of l-HPA. The modified steric hindrance engineering approach can be a valuable addition to the current enzyme engineering toolbox.

scholarly journals Developing an Ethanol Utilization Pathway based NADH Regeneration System in Escherichia coli

2021 ◽  
Vol 2 (9) ◽  
pp. 01-11
Author(s):  
Wenfa Ng
Keyword(s):  
Escherichia Coli ◽  
Glucose Dehydrogenase ◽  
Cofactor Regeneration ◽  
Regeneration System ◽  
Nadh Regeneration ◽  
Operating Modes ◽  
Theoretical Yield ◽  
Growing Cell ◽  
Biocatalytic Reaction ◽  
Utilization Pathway

Interests remain in searching for cofactor regeneration system with higher efficiency at lower substrate cost. Glucose dehydrogenase (GDH) system has been dominant in NADH regeneration, but it only has a theoretical yield of one NADH per glucose molecule. This work sought to explore the utility of a two-step ethanol utilization pathway (EUP) in pathway-based NADH regeneration. The pathway runs from ethanol to acetaldehyde and to acetyl-CoA with each step generating one NADH, that together results in a higher theoretical yield of two NADH per ethanol molecule. In this project, anaerobic biotransformation of ketone (acetophenone or butanone) to alcohol by cpsADH from Candida parapsilosis was used as readout for evaluating relative efficacy and operating modes for EUP cofactor regeneration in Escherichia coli BL21 (DE3). Experiment tests validated that EUP was more efficient than GDH in NADH regeneration. Further, growing cell delivered higher biotransformation efficiency compared to resting cell due to the driving force generated by cell growth. Finally, preculture or cultivation in M9 + 10 g/L ethanol medium delivered higher biotransformation efficiency compared to LB medium. Overall, EUP could help regenerate NADH in support of a biocatalytic reaction, and is more efficient in cofactor regeneration than GDH.

scholarly journals Structure-Guided Steric Hindrance Engineering of Bacillus Badies Phenylalanine Dehydrogenase for Efficient L-Homophenylalanine Synthesis

2021 ◽  
Author(s):  
Tao Wu ◽  
Xiaoqing Mu ◽  
Yuyan Xue ◽  
Yan Xu ◽  
Yao Nie
Keyword(s):  
Steric Hindrance ◽  
Degrees Of Freedom ◽  
Glucose Dehydrogenase ◽  
Reaction System ◽  
Docking Simulation ◽  
Catalytic Efficiency ◽  
Space Time ◽  
Enzyme Engineering ◽  
Phenylalanine Dehydrogenase ◽  
Phenylbutyric Acid

Abstract Background: Direct reductive amination of prochiral 2-oxo-4-phenylbutyric acid (2-OPBA) catalyzed by phenylalanine dehydrogenase (PheDH) is highly attractive in the synthesis of the pharmaceutical chiral building block L-homophenylalanine (L-HPA) given that its sole expense is ammonia and that water is the only byproduct. Current issues in this field include a poor catalytic efficiency and a low substrate loading.Results: In this study, we report a structure-guided steric hindrance engineering of PheDH from Bacillus badies to create an enhanced biocatalyst for efficient L-HPA synthesis. Mutagenesis libraries based on molecular docking, double-proximity filtering, and a degenerate codon significantly increased catalytic activity. Seven superior mutants were acquired, and the optimal triple-site mutant V309G/L306V/V144G showed a 12.9-fold higher kcat/Km value than wild-type. A paired reaction system comprising V309G/L306V/V144G and glucose dehydrogenase converted 1.08 M 2-OPBA to L-HPA in 210 min, and the specific space-time conversion was 30.9 mmoL·g−1·L−1·h−1. The substrate loading and specific space-time conversion are the highest values to date. Docking simulation revealed increases in substrate-binding volume and additional degrees of freedom of the substrate 2-OPBA in the pocket. Tunnel analysis suggested the formation of new enzyme tunnels and the expansion of existing ones.Conclusions: Overall, the results show that the mutant V309G/L306V/V144G has the potential for the industrial synthesis of L-HPA. The modified steric hindrance engineering approach can be a valuable addition to the current enzyme engineering toolbox.

scholarly journals Developing an ethanol utilisation pathway based NADH regeneration system in Escherichia coli

2021 ◽  
Author(s):  
Wenfa Ng
Keyword(s):  
Growth Medium ◽  
Glucose Dehydrogenase ◽  
Cofactor Regeneration ◽  
Medium Effect ◽  
Regeneration System ◽  
Nadh Regeneration ◽  
Resting Cell ◽  
Growing Cell ◽  
Ethanol Medium ◽  
Dehydrogenase System

AbstractMany industrially relevant biotransformation in whole-cells are dependent on cofactors such as NADH or NADPH. Cofactor regeneration is an established approach for providing a cheap source of cofactors in support of the main biotransformation reaction in biocatalysis. In essence, cofactor regeneration uses a sacrificial substrate to help regenerate a cofactor consumed by the main biotransformation reaction. Enzymatic in nature, alternative cofactor regeneration systems with high efficiency and which utilises low cost sacrificial substrate are of interest. Glucose dehydrogenase system has been dominant in NADH regeneration. But, in its current incarnation, glucose dehydrogenase system is relatively inefficient in regenerating NADH with theoretical yield of one NADH per glucose molecule. This work sought to explore the utility of a two-gene ethanol utilisation pathway in NADH regeneration. Comprising the first step that takes ethanol to acetaldehyde, and a second step that converts acetaldehyde to acetyl-CoA, NADH from both steps could be mined for supporting biotransformation reaction in cofactor regeneration mode. Theoretically, ethanol utilisation pathway (EUP) affords a higher NADH yield of two NADH per ethanol molecule, and is therefore more efficient than glucose dehydrogenase (GDH) system. In this project, the EUP pathway was coupled to a cpsADH (an alcohol dehydrogenase from Candida parapsilosis) mediated ketone to alcohol anaerobic biotransformation with concentration of alcohol product as marker for efficiency of cofactor regeneration. Experiment tests showed that EUP was more efficient than GDH. Further, EUP could support biotransformation of both butanone and acetophenone in single and two-phase biotransformation, respectively. Additional work conducted to improve biotransformation efficiency revealed that ethanol provision positively correlated with biotransformation efficiency. Growing cell biotransformation was also found to improve biotransformation efficiency compared to resting cell due largely to the driving force generated by cell growth. Tests of a growth medium effect also found that cells cultivated in M9 ethanol medium delivered higher biotransformation efficiency compared to those cultivated in LB medium. This could arise due to the lower expression of NADH dependent enzymes during growth in M9 ethanol medium compared to LB medium that allowed more NADH to be diverted to support ketone biotransformation. However, a persistent problem with the experimental system is the relatively poor consumption of ethanol that points to need for further engineering of the system. Collectively, pathway-based NADH regeneration is possible with ethanol utilisation, with biotransformation efficiency dependent on mode of biotransformation (resting cell versus growing cell) and growth medium used.

scholarly journals A Redox-Neutral, Two-Enzyme Cascade for the Production of Malate and Gluconate from Pyruvate and Glucose

2021 ◽  
Vol 11 (11) ◽  
pp. 4877
Author(s):  
Ravneet Mandair ◽  
Pinar Karagoz ◽  
Roslyn M. Bill
Keyword(s):  
Malate Dehydrogenase ◽  
Closed System ◽  
Glucose Dehydrogenase ◽  
Sulfolobus Solfataricus ◽  
Cofactor Regeneration ◽  
Triple Mutant ◽  
Thermococcus Kodakarensis ◽  
Platform Chemicals ◽  
Enzyme Cascade

A triple mutant of NADP(H)-dependent malate dehydrogenase from thermotolerant Thermococcus kodakarensis has an altered cofactor preference for NAD+, as well as improved malate production compared to wildtype malate dehydrogenase. By combining mutant malate dehydrogenase with glucose dehydrogenase from Sulfolobus solfataricus and NAD+/NADH in a closed reaction environment, gluconate and malate could be produced from pyruvate and glucose. After 3 h, the yield of malate was 15.96 mM. These data demonstrate the feasibility of a closed system capable of cofactor regeneration in the production of platform chemicals.

Sign in / Sign up

Export Citation Format

Share Document