1
|
Neoh SZ, Tan HT, Trakunjae C, Chek MF, Vaithanomsat P, Hakoshima T, Sudesh K. N-terminal truncation of PhaC BP-M-CPF4 and its effect on PHA production. Microb Cell Fact 2024; 23:52. [PMID: 38360657 PMCID: PMC10867992 DOI: 10.1186/s12934-024-02329-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 02/07/2024] [Indexed: 02/17/2024] Open
Abstract
BACKGROUND Among the polyhydroxyalkanoate (PHA), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] is reported to closely resemble polypropylene and low-density polyethylene. Studies have shown that PHA synthase (PhaC) from mangrove soil (PhaCBP-M-CPF4) is an efficient PhaC for P(3HB-co-3HHx) production and N-termini of PhaCs influence its substrate specificity, dimerization, granule morphology, and molecular weights of PHA produced. This study aims to further improve PhaCBP-M-CPF4 through N-terminal truncation. RESULTS The N-terminal truncated mutants of PhaCBP-M-CPF4 were constructed based on the information of the predicted secondary and tertiary structures using PSIPRED server and AlphaFold2 program, respectively. The N-terminal truncated PhaCBP-M-CPF4 mutants were evaluated in C. necator mutant PHB-4 based on the cell dry weight, PHA content, 3HHx molar composition, molecular weights, and granule morphology of the PHA granules. The results showed that most transformants harbouring the N-terminal truncated PhaCBP-M-CPF4 showed a reduction in PHA content and cell dry weight except for PhaCBP-M-CPF4 G8. PhaCBP-M-CPF4 G8 and A27 showed an improved weight-average molecular weight (Mw) of PHA produced due to lower expression of the truncated PhaCBP-M-CPF4. Transformants harbouring PhaCBP-M-CPF4 G8, A27, and T74 showed a reduction in the number of granules. PhaCBP-M-CPF4 G8 produced higher Mw PHA in mostly single larger PHA granules with comparable production as the full-length PhaCBP-M-CPF4. CONCLUSION This research showed that N-terminal truncation had effects on PHA accumulation, substrate specificity, Mw, and granule morphology. This study also showed that N-terminal truncation of the amino acids that did not adopt any secondary structure can be an alternative to improve PhaCs for the production of PHA with higher Mw in mostly single larger granules.
Collapse
Affiliation(s)
- Soon Zher Neoh
- Ecobiomaterial Research Laboratory, School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Penang, Malaysia
| | - Hua Tiang Tan
- Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan
| | - Chanaporn Trakunjae
- Kasetsart Agricultural and Agro-Industrial Product Improvement Institute (KAPI), Kasetsart University, Bangkok, 10900, Thailand
| | - Min Fey Chek
- Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan
| | - Pilanee Vaithanomsat
- Kasetsart Agricultural and Agro-Industrial Product Improvement Institute (KAPI), Kasetsart University, Bangkok, 10900, Thailand
| | - Toshio Hakoshima
- Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara, 630-0192, Japan
| | - Kumar Sudesh
- Ecobiomaterial Research Laboratory, School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Penang, Malaysia.
| |
Collapse
|
2
|
Miu DM, Eremia MC, Moscovici M. Polyhydroxyalkanoates (PHAs) as Biomaterials in Tissue Engineering: Production, Isolation, Characterization. MATERIALS 2022; 15:ma15041410. [PMID: 35207952 PMCID: PMC8875380 DOI: 10.3390/ma15041410] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Revised: 01/30/2022] [Accepted: 02/07/2022] [Indexed: 12/21/2022]
Abstract
Polyhydroxyalkanoates (PHAs) are biodegradable and biocompatible biopolymers. These biomaterials have grown in importance in the fields of tissue engineering and tissue reconstruction for structural applications where tissue morphology is critical, such as bone, cartilage, blood vessels, and skin, among others. Furthermore, they can be used to accelerate the regeneration in combination with drugs, as drug delivery systems, thus reducing microbial infections. When cells are cultured under stress conditions, a wide variety of microorganisms produce them as a store of intracellular energy in the form of homo- and copolymers of [R]—hydroxyalkanoic acids, depending on the carbon source used for microorganism growth. This paper gives an overview of PHAs, their biosynthetic pathways, producing microorganisms, cultivation bioprocess, isolation, purification and characterization to obtain biomaterials with medical applications such as tissue engineering.
Collapse
Affiliation(s)
- Dana-Maria Miu
- The National Institute for Chemical Pharmaceutical Research & Development, 031299 Bucharest, Romania; (D.-M.M.); (M.M.)
- Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 011061 Bucharest, Romania
| | - Mihaela Carmen Eremia
- The National Institute for Chemical Pharmaceutical Research & Development, 031299 Bucharest, Romania; (D.-M.M.); (M.M.)
- Correspondence:
| | - Misu Moscovici
- The National Institute for Chemical Pharmaceutical Research & Development, 031299 Bucharest, Romania; (D.-M.M.); (M.M.)
| |
Collapse
|
3
|
Phan HT, Hosoe Y, Guex M, Tomoi M, Tomita H, Zinn M, Matsumoto K. Directed Evolution of Sequence-Regulating Polyhydroxyalkanoate Synthase to Synthesize a Medium-Chain-Length-Short-Chain-Length (MCL-SCL) Block Copolymer. Biomacromolecules 2022; 23:1221-1231. [PMID: 34991313 DOI: 10.1021/acs.biomac.1c01480] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Sequence-regulating polyhydroxyalkanoate synthase PhaCAR is a chimeric enzyme comprising PhaCs from Aeromonas caviae and Ralstonia eutropha (Cupriavidus necator). It spontaneously synthesizes a short-chain-length (SCL, ≤C5) block copolymer poly(2-hydroxybutyrate)-b-poly(3-hydroxybutyrate) [P(2HB)-b-P(3HB)] from a mixture of monomer substrates. In this study, directed evolution of PhaCAR was performed to increase its activity toward a medium-chain-length (MCL, C6-12) monomer, 3-hydroxyhexanoyl (3HHx)-coenzyme A (CoA). Random mutagenesis and selection based on P(3HB-co-3HHx) production in Escherichia coli found that beneficial mutations N149D and F314L increase the 3HHx fraction. The site-directed saturation mutagenesis at position 314, which is adjacent to the catalytic center C315, demonstrated that F314H synthesizes the P(3HHx) homopolymer. The F314H mutant exhibited increased activity toward 3HHx-CoA compared with the parent enzyme, whereas the activity toward 3HB-CoA decreased. The predicted tertiary structure of PhaCAR by AlphaFold2 provided insight into the mechanism of the beneficial mutations. In addition, this finding enabled the synthesis of a new PHA block copolymer, P(3HHx)-b-P(2HB). Solvent fractionation indicated the presence of a covalent linkage between the polymer segments. This novel MCL-SCL block copolymer considerably expands the range of the molecular design of PHA block copolymers.
Collapse
Affiliation(s)
- Hien Thi Phan
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Yumi Hosoe
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Maureen Guex
- Institute of Life Technologies, University of Applied Sciences and Arts Western Switzerland (HES-SO Valais-Wallis), 1950 Sion, Switzerland
| | - Masayoshi Tomoi
- Course of Applied Chemistry, Department of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Hiroya Tomita
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| | - Manfred Zinn
- Institute of Life Technologies, University of Applied Sciences and Arts Western Switzerland (HES-SO Valais-Wallis), 1950 Sion, Switzerland
| | - Ken'ichiro Matsumoto
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan
| |
Collapse
|
4
|
Kageyama Y, Tomita H, Isono T, Satoh T, Matsumoto K. Artificial polyhydroxyalkanoate poly[2-hydroxybutyrate-block-3-hydroxybutyrate] elastomer-like material. Sci Rep 2021; 11:22446. [PMID: 34789822 PMCID: PMC8599675 DOI: 10.1038/s41598-021-01828-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 11/03/2021] [Indexed: 11/09/2022] Open
Abstract
The first polyhydroxyalkanoate (PHA) block copolymer poly(2-hydroxybutyrate-b-3-hydroxybutyrate) [P(2HB-b-3HB)] was previously synthesized using engineered Escherichia coli expressing a chimeric PHA synthase PhaCAR with monomer sequence-regulating capacity. In the present study, the physical properties of the block copolymer and its relevant random copolymer P(2HB-ran-3HB) were evaluated. Stress-strain tests on the P(88 mol% 2HB-b-3HB) film showed an increasing stress value during elongation up to 393%. In addition, the block copolymer film exhibited slow contraction behavior after elongation, indicating that P(2HB-b-3HB) is an elastomer-like material. In contrast, the P(92 mol% 2HB-ran-3HB) film, which was stretched up to 692% with nearly constant stress, was stretchable but not elastic. The differential scanning calorimetry and wide-angle X-ray diffraction analyses indicated that the P(2HB-b-3HB) contained the amorphous P(2HB) phase and the crystalline P(3HB) phase, whereas P(2HB-ran-3HB) was wholly amorphous. Therefore, the elasticity of P(2HB-b-3HB) can be attributed to the presence of the crystalline P(3HB) phase and a noncovalent crosslinked structure by the crystals. These results show the potential of block PHAs as elastic materials.
Collapse
Affiliation(s)
- Yuki Kageyama
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan
| | - Hiroya Tomita
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan
| | - Takuya Isono
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan
| | - Toshifumi Satoh
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan
| | - Ken'ichiro Matsumoto
- Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, N13W8, Kitaku, Sapporo, 060-8628, Japan.
| |
Collapse
|
5
|
Li M, Ma Y, Zhang X, Zhang L, Chen X, Ye JW, Chen GQ. Tailor-Made Polyhydroxyalkanoates by Reconstructing Pseudomonas Entomophila. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2102766. [PMID: 34322928 DOI: 10.1002/adma.202102766] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/29/2021] [Indexed: 06/13/2023]
Abstract
Microbial polyhydroxyalkanoates (PHA) containing short- and medium/long-chain-length monomers, abbreviated as SCL-co-MCL/LCL PHAs, generate suitable thermal and mechanical properties. However, SCL-co-MCL/LCL PHAs with carbon chain longer than nine are difficult to synthesize due to the low specificity of PHA synthase PhaC and the lack of either SCL- or MCL/LCL monomer precursor fluxes. This study succeeds in reprogramming a β-oxidation weakened Pseudomonas entomophila containing synthesis pathways of SCL 3-hydroxybutyryl-CoA (3HB) from glucose and MCL/LCL 3-hydroxyalkanoyl-CoA from fatty acids with carbon chain lengths from 9 to 18, respectively, that are polymerized under a low specificity PhaC61-3 to form P(3HB-co-MCL/LCL 3HA) copolymers. Through rational flux-tuning approaches, the optimized recombinant P. entomophila accumulates 55 wt% poly-3-hydroxybutyrate in 8.4 g L-1 cell dry weight. Combined with weakened β-oxidation, a series of novel P(3HB-co-MCL/LCL 3HA) copolymers with over 60 wt% PHA in 9 g L-1 cell dry weight have been synthesized for the first time. P. entomophila has become a high-performing platform to generate tailor-made new SCL-co-MCL/LCL PHAs.
Collapse
Affiliation(s)
- Mengyi Li
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Yueyuan Ma
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xu Zhang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Lizhan Zhang
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Xinyu Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
| | - Jian-Wen Ye
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Guo-Qiang Chen
- School of Life Sciences, Tsinghua University, Beijing, 100084, China
- Tsinghua-Peking Center of Life Sciences, Tsinghua University, Beijing, 100084, China
- MOE Key Lab of Industrial Biocatalysts, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China
| |
Collapse
|
6
|
Silva JB, Pereira JR, Marreiros BC, Reis MA, Freitas F. Microbial production of medium-chain length polyhydroxyalkanoates. Process Biochem 2021. [DOI: 10.1016/j.procbio.2021.01.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
7
|
Sohn YJ, Kim HT, Jo SY, Song HM, Baritugo KA, Pyo J, Choi JI, Joo JC, Park SJ. Recent Advances in Systems Metabolic Engineering Strategies for the Production of Biopolymers. BIOTECHNOL BIOPROC E 2020. [DOI: 10.1007/s12257-019-0508-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
8
|
|
9
|
Choi SY, Cho IJ, Lee Y, Kim YJ, Kim KJ, Lee SY. Microbial Polyhydroxyalkanoates and Nonnatural Polyesters. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e1907138. [PMID: 32249983 DOI: 10.1002/adma.201907138] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 01/20/2020] [Indexed: 06/11/2023]
Abstract
Microorganisms produce diverse polymers for various purposes such as storing genetic information, energy, and reducing power, and serving as structural materials and scaffolds. Among these polymers, polyhydroxyalkanoates (PHAs) are microbial polyesters synthesized and accumulated intracellularly as a storage material of carbon, energy, and reducing power under unfavorable growth conditions in the presence of excess carbon source. PHAs have attracted considerable attention for their wide range of applications in industrial and medical fields. Since the first discovery of PHA accumulating bacteria about 100 years ago, remarkable advances have been made in the understanding of PHA biosynthesis and metabolic engineering of microorganisms toward developing efficient PHA producers. Recently, nonnatural polyesters have also been synthesized by metabolically engineered microorganisms, which opened a new avenue toward sustainable production of more diverse plastics. Herein, the current state of PHAs and nonnatural polyesters is reviewed, covering mechanisms of microbial polyester biosynthesis, metabolic pathways, and enzymes involved in biosynthesis of short-chain-length PHAs, medium-chain-length PHAs, and nonnatural polyesters, especially 2-hydroxyacid-containing polyesters, metabolic engineering strategies to produce novel polymers and enhance production capabilities and fermentation, and downstream processing strategies for cost-effective production of these microbial polyesters. In addition, the applications of PHAs and prospects are discussed.
Collapse
Affiliation(s)
- So Young Choi
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - In Jin Cho
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Youngjoon Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| | - Yeo-Jin Kim
- School of Life Sciences (KNU Creative BioResearch Group), KNU Institute for Microorganisms, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, 41566, Republic of Korea
| | - Kyung-Jin Kim
- School of Life Sciences (KNU Creative BioResearch Group), KNU Institute for Microorganisms, Kyungpook National University, 80 Daehak-ro, Buk-gu, Daegu, 41566, Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
- BioProcess Engineering Research Center and Bioinformatics Research Center, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea
| |
Collapse
|
10
|
Metabolic engineering for the synthesis of polyesters: A 100-year journey from polyhydroxyalkanoates to non-natural microbial polyesters. Metab Eng 2020; 58:47-81. [DOI: 10.1016/j.ymben.2019.05.009] [Citation(s) in RCA: 93] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 05/04/2019] [Accepted: 05/26/2019] [Indexed: 11/16/2022]
|
11
|
Rigouin C, Lajus S, Ocando C, Borsenberger V, Nicaud JM, Marty A, Avérous L, Bordes F. Production and characterization of two medium-chain-length polydroxyalkanoates by engineered strains of Yarrowia lipolytica. Microb Cell Fact 2019; 18:99. [PMID: 31151440 PMCID: PMC6545009 DOI: 10.1186/s12934-019-1140-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 05/17/2019] [Indexed: 11/24/2022] Open
Abstract
Background The oleaginous yeast Yarrowia lipolytica is an organism of choice for the tailored production of various compounds such as biofuels or biopolymers. When properly engineered, it is capable of producing medium-chain-length polyhydroxyalkanoate (mcl-PHA), a biobased and biodegradable polymer that can be used as bioplastics or biopolymers for environmental and biomedical applications. Results This study describes the bioproduction and the main properties of two different mcl-PHA polymers. We generated by metabolic engineering, strains of Y. lipolytica capable of accumulating more than 25% (g/g) of mcl-PHA polymers. Depending of the strain genetic background and the culture conditions, we produced (i) a mcl-PHA homopolymer of 3-hydroxydodecanoic acids, with a mass-average molar mass (Mw) of 316,000 g/mol, showing soft thermoplastic properties with potential applications in packaging and (ii) a mcl-PHA copolymer made of 3-hydroxyoctanoic (3HO), decanoic (3HD), dodecanoic (3HDD) and tetradecanoic (3TD) acids with a Mw of 128,000 g/mol, behaving like a thermoplastic elastomer with potential applications in biomedical material. Conclusion The ability to engineer Y. lipolytica to produce tailored PHAs together with the range of possible applications regarding their biophysical and mechanical properties opens new perspectives in the field of PHA bioproduction. Electronic supplementary material The online version of this article (10.1186/s12934-019-1140-y) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Coraline Rigouin
- LISBP, CNRS, INRA, INSA, Université de Toulouse, Toulouse, France
| | - Sophie Lajus
- LISBP, CNRS, INRA, INSA, Université de Toulouse, Toulouse, France
| | - Connie Ocando
- BioTeam/ICPEES-ECPM, UMR CNRS 7515, Université de Strasbourg, 25 rue Becquerel, 67087, Strasbourg Cedex 2, France
| | | | - Jean Marc Nicaud
- Micalis Institute, INRA-AgroParisTech, UMR1319, Team BIMLip: Integrative Metabolism of Microbial Lipids, Domaine de Vilvert, 78352, Jouy-en-Josas, France
| | - Alain Marty
- Carbios - Biopôle Clermont-Limagne, 3 rue Emile Duclaux, 63360, Saint-Beauzire, France
| | - Luc Avérous
- BioTeam/ICPEES-ECPM, UMR CNRS 7515, Université de Strasbourg, 25 rue Becquerel, 67087, Strasbourg Cedex 2, France
| | - Florence Bordes
- LISBP, CNRS, INRA, INSA, Université de Toulouse, Toulouse, France.
| |
Collapse
|
12
|
Lee Y, Cho IJ, Choi SY, Lee SY. Systems Metabolic Engineering Strategies for Non-Natural Microbial Polyester Production. Biotechnol J 2019; 14:e1800426. [PMID: 30851138 DOI: 10.1002/biot.201800426] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 01/04/2019] [Indexed: 11/07/2022]
Abstract
Plastics, used everyday, are mostly synthetic polymers derived from fossil resources, and their accumulation is becoming a serious concern worldwide. Polyhydroxyalkanoates (PHAs) are naturally produced polyesters synthesized and intracellularly accumulated by many different microorganisms. PHAs are good alternatives to petroleum-based plastics because they possess a wide range of material properties depending on monomer types and molecular weights. In addition, PHAs are biodegradable and can be produced from renewable biomass. Thus, producing PHAs through the development of high-performance engineered microorganisms and efficient bioprocesses gained much interest. In addition, non-natural polyesters comprising 2-hydroxycarboxylic acids as monomers have been produced by fermentation of metabolically engineered bacteria. For example, poly(lactic acid) and poly(lactic acid-co-glycolic acid), which have been chemically synthesized using the corresponding monomers either fermentatively or chemically produced, can be produced by metabolically engineered bacteria by one-step fermentation. Recently, PHAs containing aromatic monomers could be produced by fermentation of metabolically engineered bacteria. Here, metabolic engineering strategies applied in developing microbial strains capable of producing non-natural polyesters in a stepwise manner are reviewed. It is hoped that the detailed strategies described will be helpful for designing metabolic engineering strategies for developing diverse microbial strains capable of producing various polymers that can replace petroleum-derived polymers.
Collapse
Affiliation(s)
- Youngjoon Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.,Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - In J Cho
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.,Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - So Y Choi
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.,Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.,Applied Science Research Institute, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| | - Sang Y Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon, 34141, Republic of Korea.,Systems Metabolic Engineering and Systems Healthcare Cross-Generation Collaborative Laboratory, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.,Applied Science Research Institute, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.,BioInformatics Research Center, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea.,BioProcess Engineering Research Center, Korea Advanced Institute of Science and Technology, Daejeon, 34141, Republic of Korea
| |
Collapse
|
13
|
Mezzolla V, D'Urso OF, Poltronieri P. Role of PhaC Type I and Type II Enzymes during PHA Biosynthesis. Polymers (Basel) 2018; 10:polym10080910. [PMID: 30960835 PMCID: PMC6403647 DOI: 10.3390/polym10080910] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 08/09/2018] [Accepted: 08/09/2018] [Indexed: 11/20/2022] Open
Abstract
PHA synthases (PhaC) are grouped into four classes based on the kinetics and mechanisms of reaction. The grouping of PhaC enzymes into four classes is dependent on substrate specificity, according to the preference in forming short-chain-length (scl) or medium-chain-length (mcl) polymers: Class I, Class III and Class IV produce scl-PHAs depending on propionate, butyrate, valerate and hexanoate precursors, while Class II PhaC synthesize mcl-PHAs based on the alkane (C6 to C14) precursors. PHA synthases of Class I, in particular PhaCCs from Chromobacterium USM2 and PhaCCn/RePhaC1 from Cupriavidus necator/Ralstonia eutropha, have been analysed and the crystal structures of the C-domains have been determined. PhaCCn/RePhaC1 was also studied by X-ray absorption fine-structure (XAFS) analysis. Models have been proposed for dimerization, catalysis mechanism, substrate recognition and affinity, product formation, and product egress route. The assays based on amino acid substitution by mutagenesis have been useful to validate the hypothesis on the role of amino acids in catalysis and in accommodation of bulky substrates, and for the synthesis of PHB copolymers and medium-chain-length PHA polymers with optimized chemical properties.
Collapse
Affiliation(s)
- Valeria Mezzolla
- Department of Biological and Environmental Science and Technologies, University of Salento, Ecotekne, 73100 Lecce, Italy.
| | - Oscar Fernando D'Urso
- Department of Biological and Environmental Science and Technologies, University of Salento, Ecotekne, 73100 Lecce, Italy.
| | - Palmiro Poltronieri
- CNR, Agrofood Department, Institute of Sciences of Food Productions (ISPA-CNR), 73100 Lecce, Italy.
| |
Collapse
|
14
|
Hori C, Oishi K, Matsumoto K, Taguchi S, Ooi T. Site-directed saturation mutagenesis of polyhydroxylalkanoate synthase for efficient microbial production of poly[(R)-2-hydroxybutyrate]. J Biosci Bioeng 2018; 125:632-636. [DOI: 10.1016/j.jbiosc.2017.11.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 11/22/2017] [Accepted: 11/30/2017] [Indexed: 11/30/2022]
|
15
|
Scheel RA, Ji L, Lundgren BR, Nomura CT. Enhancing poly(3-hydroxyalkanoate) production in Escherichia coli by the removal of the regulatory gene arcA. AMB Express 2016; 6:120. [PMID: 27878786 PMCID: PMC5120623 DOI: 10.1186/s13568-016-0291-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 11/09/2016] [Indexed: 11/18/2022] Open
Abstract
Recombinant Escherichia coli is a desirable platform for the production of many biological compounds including poly(3-hydroxyalkanoates), a class of naturally occurring biodegradable polyesters with promising biomedical and material applications. Although the controlled production of desirable polymers is possible with the utilization of fatty acid feedstocks, a central challenge to this biosynthetic route is the improvement of the relatively low polymer yield, a necessary factor of decreasing the production costs. In this study we sought to address this challenge by deleting arcA and ompR, two global regulators with the capacity to inhibit the uptake and activation of exogenous fatty acids. We found that polymer yields in a ΔarcA mutant increased significantly with respect to the parental strain. In the parental strain, PHV yields were very low but improved 64-fold in the ΔarcA mutant (1.92-124 mg L-1) The ΔarcA mutant also allowed for modest increases in some medium chain length polymer yields, while weight average molecular weights improved by approximately 1.5-fold to 12-fold depending on the fatty acid substrate utilized. These results were supported by an analysis of differential gene expression, which showed that the key genes (fadD, fadL, and fadE) encoding fatty acid degradation enzymes were all upregulated by 2-, 10-, and 31-fold in an ΔarcA mutant, respectively. Additionally, the short chain length fatty acid uptake genes atoA, atoE and atoD were upregulated by 103-, 119-, and 303-fold respectively, though these values are somewhat inflated due to low expression in the parental strain. Overall, this study demonstrates that arcA is an important target to improve PHA production from fatty acids.
Collapse
Affiliation(s)
- Ryan A. Scheel
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, 1 Forestry Drive, Syracuse, NY 13210 USA
| | - Liyuan Ji
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, 1 Forestry Drive, Syracuse, NY 13210 USA
| | - Benjamin R. Lundgren
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, 1 Forestry Drive, Syracuse, NY 13210 USA
| | - Christopher T. Nomura
- Department of Chemistry, State University of New York College of Environmental Science and Forestry, 1 Forestry Drive, Syracuse, NY 13210 USA
- Center for Applied Microbiology, State University of New York College of Environmental Science and Forestry, 1 Forestry Drive, Syracuse, NY 13210 USA
- Hubei Collaborative Center for Green Transformation of Bio-Resources, College of Life Sciences, Hubei University, Wuhan, 430062 China
| |
Collapse
|
16
|
Engineered biosynthesis of biodegradable polymers. ACTA ACUST UNITED AC 2016; 43:1037-58. [DOI: 10.1007/s10295-016-1785-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 05/21/2016] [Indexed: 10/21/2022]
Abstract
Abstract
Advances in science and technology have resulted in the rapid development of biobased plastics and the major drivers for this expansion are rising environmental concerns of plastic pollution and the depletion of fossil-fuels. This paper presents a broad view on the recent developments of three promising biobased plastics, polylactic acid (PLA), polyhydroxyalkanoate (PHA) and polybutylene succinate (PBS), well known for their biodegradability. The article discusses the natural and recombinant host organisms used for fermentative production of monomers, alternative carbon feedstocks that have been used to lower production cost, different metabolic engineering strategies used to improve product titers, various fermentation technologies employed to increase productivities and finally, the different downstream processes used for recovery and purification of the monomers and polymers.
Collapse
|
17
|
Cheng J, Charles TC. Novel polyhydroxyalkanoate copolymers produced in Pseudomonas putida by metagenomic polyhydroxyalkanoate synthases. Appl Microbiol Biotechnol 2016; 100:7611-27. [PMID: 27333909 DOI: 10.1007/s00253-016-7666-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 06/01/2016] [Accepted: 06/04/2016] [Indexed: 10/21/2022]
Abstract
Bacterially produced biodegradable polyhydroxyalkanoates (PHAs) with versatile properties can be achieved using different PHA synthases (PhaCs). This work aims to expand the diversity of known PhaCs via functional metagenomics and demonstrates the use of these novel enzymes in PHA production. Complementation of a PHA synthesis-deficient Pseudomonas putida strain with a soil metagenomic cosmid library retrieved 27 clones expressing either class I, class II, or unclassified PHA synthases, and many did not have close sequence matches to known PhaCs. The composition of PHA produced by these clones was dependent on both the supplied growth substrates and the nature of the PHA synthase, with various combinations of short-chain-length (SCL) and medium-chain-length (MCL) PHA. These data demonstrate the ability to isolate diverse genes for PHA synthesis by functional metagenomics and their use for the production of a variety of PHA polymer and copolymer mixtures.
Collapse
Affiliation(s)
- Jiujun Cheng
- Department of Biology and Centre for Bioengineering and Biotechnology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Trevor C Charles
- Department of Biology and Centre for Bioengineering and Biotechnology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada.
| |
Collapse
|
18
|
|
19
|
Advanced bacterial polyhydroxyalkanoates: Towards a versatile and sustainable platform for unnatural tailor-made polyesters. Biotechnol Adv 2012; 30:1196-206. [DOI: 10.1016/j.biotechadv.2011.11.007] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2011] [Revised: 11/01/2011] [Accepted: 11/15/2011] [Indexed: 11/22/2022]
|
20
|
Tappel RC, Kucharski JM, Mastroianni JM, Stipanovic AJ, Nomura CT. Biosynthesis of Poly[(R)-3-hydroxyalkanoate] Copolymers with Controlled Repeating Unit Compositions and Physical Properties. Biomacromolecules 2012; 13:2964-72. [DOI: 10.1021/bm301043t] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ryan C. Tappel
- Chemistry Department, State University of New York − College of Environmental Science
and Forestry, 1 Forestry Drive, Syracuse, New York 13210, United States
| | - Jason M. Kucharski
- Chemistry Department, State University of New York − College of Environmental Science
and Forestry, 1 Forestry Drive, Syracuse, New York 13210, United States
| | - Jessica M. Mastroianni
- Chemistry Department, State University of New York − College of Environmental Science
and Forestry, 1 Forestry Drive, Syracuse, New York 13210, United States
| | - Arthur J. Stipanovic
- Chemistry Department, State University of New York − College of Environmental Science
and Forestry, 1 Forestry Drive, Syracuse, New York 13210, United States
| | - Christopher T. Nomura
- Chemistry Department, State University of New York − College of Environmental Science
and Forestry, 1 Forestry Drive, Syracuse, New York 13210, United States
| |
Collapse
|
21
|
Wang Q, Xia Y, Chen Q, Qi Q. Incremental truncation of PHA synthases results in altered product specificity. Enzyme Microb Technol 2012; 50:293-7. [DOI: 10.1016/j.enzmictec.2012.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2011] [Revised: 02/16/2012] [Accepted: 02/18/2012] [Indexed: 10/28/2022]
|
22
|
Tappel RC, Wang Q, Nomura CT. Precise control of repeating unit composition in biodegradable poly(3-hydroxyalkanoate) polymers synthesized by Escherichia coli. J Biosci Bioeng 2012; 113:480-6. [DOI: 10.1016/j.jbiosc.2011.12.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 12/09/2011] [Accepted: 12/12/2011] [Indexed: 11/27/2022]
|
23
|
Nduko JM, Matsumoto K, Taguchi S. Biological Lactate-Polymers Synthesized by One-Pot Microbial Factory: Enzyme and Metabolic Engineering. ACS SYMPOSIUM SERIES 2012. [DOI: 10.1021/bk-2012-1105.ch014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- John Masani Nduko
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, N13W8, Kita-ku, Sapporo 060-8628, Japan
| | - Ken’ichiro Matsumoto
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, N13W8, Kita-ku, Sapporo 060-8628, Japan
| | - Seiichi Taguchi
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, N13W8, Kita-ku, Sapporo 060-8628, Japan
| |
Collapse
|
24
|
Song Y, Matsumoto K, Yamada M, Gohda A, Brigham CJ, Sinskey AJ, Taguchi S. Engineered Corynebacterium glutamicum as an endotoxin-free platform strain for lactate-based polyester production. Appl Microbiol Biotechnol 2011; 93:1917-25. [PMID: 22127753 DOI: 10.1007/s00253-011-3718-0] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 10/24/2011] [Accepted: 10/26/2011] [Indexed: 11/24/2022]
Abstract
The first biosynthetic system for lactate (LA)-based polyesters was previously created in recombinant Escherichia coli (Taguchi et al. 2008). Here, we have begun efforts to upgrade the prototype polymer production system to a practical stage by using metabolically engineered Gram-positive bacterium Corynebacterium glutamicum as an endotoxin-free platform. We designed metabolic pathways in C. glutamicum to generate monomer substrates, lactyl-CoA (LA-CoA), and 3-hydroxybutyryl-CoA (3HB-CoA), for the copolymerization catalyzed by the LA-polymerizing enzyme (LPE). LA-CoA was synthesized by D: -lactate dehydrogenase and propionyl-CoA transferase, while 3HB-CoA was supplied by β-ketothiolase (PhaA) and NADPH-dependent acetoacetyl-CoA reductase (PhaB). The functional expression of these enzymes led to a production of P(LA-co-3HB) with high LA fractions (96.8 mol%). The omission of PhaA and PhaB from this pathway led to a further increase in LA fraction up to 99.3 mol%. The newly engineered C. glutamicum potentially serves as a food-grade and biomedically applicable platform for the production of poly(lactic acid)-like polyester.
Collapse
Affiliation(s)
- Yuyang Song
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo, 060-8628, Japan
| | | | | | | | | | | | | |
Collapse
|
25
|
Park SJ, Lee SY, Kim TW, Jung YK, Yang TH. Biosynthesis of lactate-containing polyesters by metabolically engineered bacteria. Biotechnol J 2011; 7:199-212. [PMID: 22057878 DOI: 10.1002/biot.201100070] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 07/06/2011] [Accepted: 08/05/2011] [Indexed: 11/09/2022]
Abstract
Due to increasing concerns about environmental problems, climate change and limited fossil resources, bio-based production of chemicals and polymers is gaining attention as one of the solutions to these problems. Polyhydroxyalkanoates (PHAs) are polyesters that can be produced by microbial fermentation. PHAs are synthesized using monomer precursors provided from diverse metabolic pathways and are accumulated as distinct granules inside the cells. On the other hand, most so-called bio-based polymers including polybutylene succinate, polytrimethylene terephthalate, and polylactic acid (PLA) are synthesized by a chemical process using monomers produced by fermentation. PLA, an attractive biomass-derived plastic, is currently synthesized by heavy metal-catalyzed ring opening polymerization of L-lactide that is made from fermentation-derived L-lactic acid. Recently, a complete biological process for the production of PLA and PLA copolymers from renewable resources has been developed by direct fermentation of recombinant bacteria employing PHA biosynthetic pathways coupled with a novel metabolic pathway. This could be accomplished by establishing a pathway for generating lactyl-CoA and engineering PHA synthase to accept lactyl-CoA as a substrate combined with systems metabolic engineering. In this article, we review recent advances in the production of lactate-containing homo- and co-polyesters. Challenges remaining to efficiently produce PLA and its copolymers and strategies to overcome these challenges through metabolic engineering combined with enzyme engineering are discussed.
Collapse
Affiliation(s)
- Si Jae Park
- Chemical Biotechnology Research Center, Green Chemistry Division, Korea Research Institute of Chemical Technology, Daejeon, Republic of Korea.
| | | | | | | | | |
Collapse
|
26
|
Characterization of the highly active polyhydroxyalkanoate synthase of Chromobacterium sp. strain USM2. Appl Environ Microbiol 2011; 77:2926-33. [PMID: 21398494 DOI: 10.1128/aem.01997-10] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The synthesis of bacterial polyhydroxyalkanoates (PHA) is very much dependent on the expression and activity of a key enzyme, PHA synthase (PhaC). Many efforts are being pursued to enhance the activity and broaden the substrate specificity of PhaC. Here, we report the identification of a highly active wild-type PhaC belonging to the recently isolated Chromobacterium sp. USM2 (PhaC(Cs)). PhaC(Cs) showed the ability to utilize 3-hydroxybutyrate (3HB), 3-hydroxyvalerate (3HV), and 3-hydroxyhexanoate (3HHx) monomers in PHA biosynthesis. An in vitro assay of recombinant PhaC(Cs) expressed in Escherichia coli showed that its polymerization of 3-hydroxybutyryl-coenzyme A activity was nearly 8-fold higher (2,462 ± 80 U/g) than that of the synthase from the model strain C. necator (307 ± 24 U/g). Specific activity using a Strep2-tagged, purified PhaC(Cs) was 238 ± 98 U/mg, almost 5-fold higher than findings of previous studies using purified PhaC from C. necator. Efficient poly(3-hydroxybutyrate) [P(3HB)] accumulation in Escherichia coli expressing PhaC(Cs) of up to 76 ± 2 weight percent was observed within 24 h of cultivation. To date, this is the highest activity reported for a purified PHA synthase. PhaC(Cs) is a naturally occurring, highly active PHA synthase with superior polymerizing ability.
Collapse
|
27
|
Yang TH, Jung YK, Kang HO, Kim TW, Park SJ, Lee SY. Tailor-made type II Pseudomonas PHA synthases and their use for the biosynthesis of polylactic acid and its copolymer in recombinant Escherichia coli. Appl Microbiol Biotechnol 2011; 90:603-14. [PMID: 21221571 DOI: 10.1007/s00253-010-3077-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2010] [Revised: 12/14/2010] [Accepted: 12/15/2010] [Indexed: 11/29/2022]
Abstract
Previously, we have developed metabolically engineered Escherichia coli strains capable of producing polylactic acid (PLA) and poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)] by employing evolved Clostridium propionicum propionate CoA transferase (Pct(Cp)) and Pseudomonas sp. MBEL 6-19 polyhydroxyalkanoate (PHA) synthase 1 (PhaC1(Ps6-19)). Introduction of mutations four sites (E130, S325, S477, and Q481) of PhaC1( Ps6-19) have been found to affect the polymer content, lactate mole fraction, and molecular weight of P(3HB-co-LA). In this study, we have further engineered type II Pseudomonas PHA synthases 1 (PhaC1s) from Pseudomonas chlororaphis, Pseudomonas sp. 61-3, Pseudomonas putida KT2440, Pseudomonas resinovorans, and Pseudomonas aeruginosa PAO1 to accept short-chain-length hydroxyacyl-CoAs including lactyl-CoA and 3-hydroxybutyryl-CoA as substrates by site-directed mutagenesis of four sites (E130, S325, S477, and Q481). All PhaC1s having mutations in these four sites were able to accept lactyl-CoA as a substrate and supported the synthesis of P(3HB-co-LA) in recombinant E. coli, whereas the wild-type PhaC1s could not accumulate polymers in detectable levels. The contents, lactate mole fractions, and the molecular weights of P(3HB-co-LA) synthesized by recombinant E. coli varied depending upon the source of the PHA synthase and the mutants used. PLA homopolymer could also be produced at ca. 7 wt.% by employing the several PhaC1 variants containing E130D/S325T/S477G/Q481K quadruple mutations in wild-type E. coli XL1-Blue.
Collapse
Affiliation(s)
- Taek Ho Yang
- Corporate R&D, LG Chem Research Park, 104-1 Moonji-dong, Yuseong-gu, Daejeon 305-380, Republic of Korea.
| | | | | | | | | | | |
Collapse
|
28
|
MATSUMOTO K. Production of Polyhydroxyalkanoate Copolymers in Transgenic Plants Expressing Engineered Enzymes. KOBUNSHI RONBUNSHU 2011. [DOI: 10.1295/koron.68.562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
29
|
MATSUMOTO K, TAGUCHI S. One-pot Production of Lactate-Based Polyesters Using Engineered Microbes Expressing Lactate-Polymerizing Enzyme. KOBUNSHI RONBUNSHU 2011. [DOI: 10.1295/koron.68.271] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
30
|
Yamada M, Matsumoto K, Shimizu K, Uramoto S, Nakai T, Shozui F, Taguchi S. Adjustable mutations in lactate (LA)-polymerizing enzyme for the microbial production of LA-based polyesters with tailor-made monomer composition. Biomacromolecules 2010; 11:815-9. [PMID: 20166718 DOI: 10.1021/bm901437z] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Lactate (LA)-polymerizing enzyme (LPE) is a newly established class of polyhydroxyalkanoate (PHA) synthase, which can incorporate LA units into a polymer chain. We previously synthesized P(LA-co-3-hydroxybutyrate)s [P(LA-co-3HB)s] in recombinant Escherichia coli using the first LPE, which is the Ser325Thr/Glu481Lys mutant of PHA synthase from Pseudomonas sp. 61-3 [PhaC1(Ps)ST/QK]. In this study, we finely regulated LA fraction in the copolymer by saturated mutations at position 392 (F392X), which corresponds to the activity-enhancing mutations at position 420 of PHA synthase from Ralstonia eutropha. Among the 19 saturated mutants of LPE at position 392, 17 mutants produced P(LA-co-3HB)s with various LA fractions (16-45 mol %), whereas PhaC1(Ps)ST/QK produced P(LA-co-3HB) with 26 mol % LA under the same culture condition. In particular, the F392S mutation exhibited the highest LA fraction of 45 mol %, and also increased polymer content (62 wt %) compared with PhaC1(Ps)ST/QK (44 wt %). Combination of the F392S mutant and anaerobic culture conditions, which promote LA production, led to a further increase in LA fraction up to 62 mol %. The P(LA-co-3HB)s with various LA fractions exhibited altered melting temperatures and melting enthalpy depending on their monomer composition. Accordingly, the mutations at position 392 in LPE greatly contributed to fine-tuning of the LA fraction in the copolymers that is useful for regulating LA fraction-dependent thermal properties.
Collapse
Affiliation(s)
- Miwa Yamada
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo 060-8628, Japan
| | | | | | | | | | | | | |
Collapse
|
31
|
Matsumoto K, Takase K, Yamamoto Y, Doi Y, Taguchi S. Chimeric enzyme composed of polyhydroxyalkanoate (PHA) synthases from Ralstonia eutropha and Aeromonas caviae enhances production of PHAs in recombinant Escherichia coli. Biomacromolecules 2010; 10:682-5. [PMID: 19226108 DOI: 10.1021/bm801386j] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Chimeric enzymes composed of polyhydroxyalkanoate (PHA) synthases from Ralstonia eutropha (Cupriavidus necator) (PhaC(Re)) and Aeromonas caviae (PhaC(Ac)) were constructed. PhaC(Re) is known for its potent enzymatic activity among the characterized PHA synthases. PhaCAc has broad substrate specificity and synthesizes short-chain-length (SCL)/medium-chain-length (MCL) PHA. We attempted to create chimeric enzymes inheriting both of the advantageous properties. Among eight chimeras, AcRe12, with 26% of the N-terminal of PhaC(Ac) and 74% of the C-terminal of PhaC(Re), exhibited comparable P(3-hydroxybutyrate) accumulation as parental enzymes in Escherichia coli JM109. Thus, AcRe12 was applied to SCL/MCL PHA production using E. coli LS5218 as the host. AcRe12 accumulated higher amount of PHA (50 wt %) than the parental enzymes. Furthermore, the PHA consisted of 2 mol % 3-hydroxyhexanoate as well as 3-hydroxybutyrate. Therefore, the chimeric PHA synthase, AcRe12, inherited the character of both of the parental enzymes and thus exhibits improved enzymatic properties.
Collapse
Affiliation(s)
- Ken'ichiro Matsumoto
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, N13-W8, Kita-ku, Sapporo 060-8628, Japan
| | | | | | | | | |
Collapse
|
32
|
Yang TH, Kim TW, Kang HO, Lee SH, Lee EJ, Lim SC, Oh SO, Song AJ, Park SJ, Lee SY. Biosynthesis of polylactic acid and its copolymers using evolved propionate CoA transferase and PHA synthase. Biotechnol Bioeng 2010; 105:150-60. [DOI: 10.1002/bit.22547] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
33
|
Enzymatic and whole-cell synthesis of lactate-containing polyesters: toward the complete biological production of polylactate. Appl Microbiol Biotechnol 2009; 85:921-32. [DOI: 10.1007/s00253-009-2374-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 11/18/2009] [Accepted: 11/18/2009] [Indexed: 10/20/2022]
|
34
|
Engineering of polyhydroxyalkanoate synthase by Ser477X/Gln481X saturation mutagenesis for efficient production of 3-hydroxybutyrate-based copolyesters. Appl Microbiol Biotechnol 2009; 84:1117-24. [DOI: 10.1007/s00253-009-2052-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Revised: 05/20/2009] [Accepted: 05/21/2009] [Indexed: 10/20/2022]
|
35
|
Matsumoto K, Murata T, Nagao R, Nomura CT, Arai S, Arai Y, Takase K, Nakashita H, Taguchi S, Shimada H. Production of Short-Chain-Length/Medium-Chain-Length Polyhydroxyalkanoate (PHA) Copolymer in the Plastid of Arabidopsis thaliana Using an Engineered 3-Ketoacyl-acyl Carrier Protein Synthase III. Biomacromolecules 2009; 10:686-90. [DOI: 10.1021/bm8013878] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ken’ichiro Matsumoto
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Takaaki Murata
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Rina Nagao
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Christopher T. Nomura
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Satoshi Arai
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Yuko Arai
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Kazuma Takase
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Hideo Nakashita
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Seiichi Taguchi
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| | - Hiroaki Shimada
- Division of Biotechnology and Macromolecular Chemistry, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628, Japan, Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda 278-8510, Japan, Department of Chemistry, College of Environmental Science and Forestry, State University of New York, 1 Forestry Drive, Syracuse, New York 13210, National Institute for Basic Biology, 38 Azanishigohnaka, Myoudaiji, Okazaki 444-8585, Japan, RIKEN Institute, 2-1
| |
Collapse
|
36
|
Matsumoto K, Shozui F, Satoh Y, Tajima K, Munekata M, Taguchi S. Kinetic Analysis of Engineered Polyhydroxyalkanoate Synthases with Broad Substrate Specificity. Polym J 2009. [DOI: 10.1295/polymj.pj2008253] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
37
|
Tsuge T, Yamamoto T, Yano K, Abe H, Doi Y, Taguchi S. Evaluating the Ability of Polyhydroxyalkanoate Synthase Mutants to Produce P(3HB-co-
3HA) from Soybean Oil. Macromol Biosci 2008; 9:71-8. [DOI: 10.1002/mabi.200800118] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
38
|
Tsuge T, Watanabe S, Sato S, Hiraishi T, Abe H, Doi Y, Taguchi S. Variation in copolymer composition and molecular weight of polyhydroxyalkanoate generated by saturation mutagenesis of Aeromonas caviae PHA synthase. Macromol Biosci 2008; 7:846-54. [PMID: 17541931 DOI: 10.1002/mabi.200700023] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Amino acid substitutions at two residues downstream from the active-site histidine of polyhydroxyalkanoate (PHA) synthases are effective for changing the composition and the molecular weight of PHA. In this study, saturation mutagenesis at the position Ala505 was applied to PHA synthase (PhaCAc) from Aeromonas caviae to investigate the effects on the composition and the molecular weight of PHA synthesized in Ralstonia eutropha. The copolymer composition and molecular weight of PHA were varied by association with amino acid substitutions. There was a strong relationship between copolymer composition and PHA synthase activity of the cells. This finding will serve as a rationale for producing tailor-made PHAs.
Collapse
Affiliation(s)
- Takeharu Tsuge
- Department of Innovative and Engineered Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama 226-8502, Japan.
| | | | | | | | | | | | | |
Collapse
|
39
|
CHEN J, ZHANG L, CHEN J, CHEN G. Biosynthesis and Characterization of Polyhydroxyalkanoate Copolyesters in Ralstonia eutropha PHB−4 Harboring a Low-Substrate-Specificity PHA Synthase PhaC2Ps from Pseudomonas stutzeri 1317. Chin J Chem Eng 2007. [DOI: 10.1016/s1004-9541(07)60097-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
40
|
Nomura CT, Taguchi S. PHA synthase engineering toward superbiocatalysts for custom-made biopolymers. Appl Microbiol Biotechnol 2007; 73:969-79. [PMID: 17123079 DOI: 10.1007/s00253-006-0566-4] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2006] [Revised: 07/09/2006] [Accepted: 07/09/2006] [Indexed: 10/23/2022]
Abstract
Poly-3-hydroxyalkanoates [P(3HA)s] are biologically produced polyesters that have attracted much attention as biodegradable polymers that can be produced from biorenewable resources. These polymers have many attractive properties for use as bulk commodity plastics, fishing lines, and medical uses that are dependent on the repeating unit structures. Despite the readily apparent benefits of using P(3HA)s as replacements for petrochemical-derived plastics, the use and distribution of P(3HA)s have been limited by their cost of production. This problem is currently being addressed by the engineering of enzymes involved in the production of P(3HA)s. Polyhydroxyalkanoate (PHA) synthase (PhaC) enzymes, which catalyze the polymerization of 3-hydroxyacyl-CoA monomers to P(3HA)s, were subjected to various forms of protein engineering to improve the enzyme activity or substrate specificity. This review covers the recent history of PHA synthase engineering and also summarizes studies that have utilized engineered PHA synthases.
Collapse
Affiliation(s)
- Christopher T Nomura
- Department of Chemistry, State University of New York - College of Environmental Science and Forestry, 121 Jahn Laboratory, Syracuse, NY 13210, USA
| | | |
Collapse
|
41
|
Matsumoto K, Aoki E, Takase K, Doi Y, Taguchi S. In Vivo and in Vitro Characterization of Ser477X Mutations in Polyhydroxyalkanoate (PHA) Synthase 1 from Pseudomonas sp. 61−3: Effects of Beneficial Mutations on Enzymatic Activity, Substrate Specificity, and Molecular Weight of PHA. Biomacromolecules 2006; 7:2436-42. [PMID: 16903693 DOI: 10.1021/bm0602029] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Evolutionary engineered polyhydroxyalkanoate (PHA) synthases from Pseudomonas sp. 61-3 enhance PHA accumulation and enable the monomer composition of PHAs to be regulated. We characterized a newly screened Ser477Arg (S477R) mutant of PHA synthase by in vivo analyses of P(3-hydroxybutyrate) [P(3HB)] homopolymer and P(3HB-co-3-hydroxyalkanoate) [P(3HB-co-3HA)] copolymer productions in the recombinants of Escherichia coli. The results indicated that the S477R mutation contributed to a shift in substrate specificity to smaller monomers containing a 3HB unit rather than to an enhancement in catalytic activity. Multiple mutations of S477R with other beneficial mutations, for example, Ser325Cys, exhibited synergistic effects on both an increase in PHA production (from 9 wt % to 21 wt %) and an alteration of substrate specificity. Furthermore, the effects of complete amino acid substitutions at position 477 were characterized in terms of in vivo PHA production and in vitro enzymatic activity. The five mutations, S477Ala(A)/Phe(F)/His(H)/Arg(R)/Tyr(Y), resulted in a shift in substrate specificity to smaller monomer units. The S477Gly(G) mutant greatly enhanced activity toward all different sizes of substrates with carbon numbers ranging from 4 to 12. These results indicated that the residue 477 contributes to both the catalytic activity and substrate specificity of PHA synthase. In recombinant E. coli, the S477A/F/G/H/R/Y mutations consistently led to increases (up to 6 times that of wild-type enzyme) in weight average molecular weights of P(3HB) homopolymers. On the basis of our studies, we created a structural feasibility accounting for the mutational effects on enzymatic activity and substrate specificity of PHA synthase.
Collapse
Affiliation(s)
- Ken'ichiro Matsumoto
- Department of Biological Science and Technology, Tokyo University of Science, Yamazaki 2641, Noda, Chiba 278-8510, Japan
| | | | | | | | | |
Collapse
|
42
|
Nomura CT, Taguchi K, Gan Z, Kuwabara K, Tanaka T, Takase K, Doi Y. Expression of 3-ketoacyl-acyl carrier protein reductase (fabG) genes enhances production of polyhydroxyalkanoate copolymer from glucose in recombinant Escherichia coli JM109. Appl Environ Microbiol 2005; 71:4297-306. [PMID: 16085817 PMCID: PMC1183366 DOI: 10.1128/aem.71.8.4297-4306.2005] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Polyhydroxyalkanoates (PHAs) are biologically produced polyesters that have potential application as biodegradable plastics. Especially important are the short-chain-length-medium-chain-length (SCL-MCL) PHA copolymers, which have properties ranging from thermoplastic to elastomeric, depending on the ratio of SCL to MCL monomers incorporated into the copolymer. Because of the potential wide range of applications for SCL-MCL PHA copolymers, it is important to develop and characterize metabolic pathways for SCL-MCL PHA production. In previous studies, coexpression of PHA synthase genes and the 3-ketoacyl-acyl carrier protein reductase gene (fabG) in recombinant Escherichia coli has been shown to enhance PHA production from related carbon sources such as fatty acids. In this study, a new fabG gene from Pseudomonas sp. 61-3 was cloned and its gene product characterized. Results indicate that the Pseudomonas sp. 61-3 and E. coli FabG proteins have different substrate specificities in vitro. The current study also presents the first evidence that coexpression of fabG genes from either E. coli or Pseudomonas sp. 61-3 with fabH(F87T) and PHA synthase genes can enhance the production of SCL-MCL PHA copolymers from nonrelated carbon sources. Differences in the substrate specificities of the FabG proteins were reflected in the monomer composition of the polymers produced by recombinant E. coli. SCL-MCL PHA copolymer isolated from a recombinant E. coli strain had improved physical properties compared to the SCL homopolymer poly-3-hydroxybutyrate. This study defines a pathway to produce SCL-MCL PHA copolymer from the fatty acid biosynthesis that may impact on PHA production in recombinant organisms.
Collapse
Affiliation(s)
- Christopher T Nomura
- Polymer Chemistry Laboratory, RIKEN Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
| | | | | | | | | | | | | |
Collapse
|
43
|
Matsumoto K, Nagao R, Murata T, Arai Y, Kichise T, Nakashita H, Taguchi S, Shimada H, Doi Y. Enhancement of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Production in the Transgenic Arabidopsis thaliana by the in Vitro Evolved Highly Active Mutants of Polyhydroxyalkanoate (PHA) Synthase from Aeromonas caviae. Biomacromolecules 2005; 6:2126-30. [PMID: 16004454 DOI: 10.1021/bm050113g] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, the enhancement of photosynthetic PHA production was achieved using the highly active mutants of PHA synthase created by the in vitro evolutionally techniques. The wild-type and mutated PHA synthase genes from Aeromonas caviae were introduced into Arabidopsis thaliana together with the NADPH-dependent acetoacetyl-CoA reductase gene from Ralstonia eutropha. Expression of the highly active mutated PHA synthase genes, N149S and D171G, led to an 8-10-fold increase in PHA content in the T1 transgenic Arabidopsis, compared to plants harboring the wild-type PHA synthase gene. In homozygous T2 progenies, PHA content was further increased up to 6.1 mg/g cell dry weight. GC/MS analysis of the purified PHA from the transformants revealed that these PHAs were poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] copolymers consisting of 0.2-0.8 mol % 3HV. The monomer composition of the P(3HB-co-3HV) copolymers synthesized by the wild-type and mutated PHA synthases reflected the substrate specificities observed in Escherichia coli. These results indicate that in vitro evolved PHA synthases can enhance the productivity of PHA and regulate the monomer composition in transgenic plants.
Collapse
Affiliation(s)
- Ken'ichiro Matsumoto
- Polymer Chemistry Laboratory, RIKEN Institute, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
| | | | | | | | | | | | | | | | | |
Collapse
|