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Hozumi Y, Hachisuka SI, Tomita H, Kikukawa H, Matsumoto K. Engineering of the Long-Main-Chain Monomer-Incorporating Polyhydroxyalkanoate Synthase PhaC AR for the Biosynthesis of Poly[( R)-3-hydroxybutyrate- co-6-hydroxyhexanoate]. Biomacromolecules 2024; 25:2973-2979. [PMID: 38588330 DOI: 10.1021/acs.biomac.4c00116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
Polyhydroxyalkanoate (PHA) synthases (PhaCs) are useful and versatile tools for the production of aliphatic polyesters. Here, the chimeric PHA synthase PhaCAR was engineered to increase its capacity to incorporate unusual 6-hydroxyhexanoate (6HHx) units. Mutations at positions 149 and 314 in PhaCAR were previously found to increase the incorporation of an analogous natural monomer, 3-hydroxyhexanoate (3HHx). We attempted to repurpose the mutations to produce 6HHx-containing polymers. Site-directed saturation mutants at these positions were applied for P(3HB-co-6HHx) synthesis in Escherichia coli. As a result, the N149D and F314Y mutants effectively increased the 6HHx fraction. Moreover, the pairwise NDFY mutation further increased the 6HHx fraction, which reached 22 mol %. This increase was presumably caused by altered enzyme activity rather than altered expression levels, as assessed based on immunoblot analysis. The glass transition temperature and crystallinity of P(3HB-co-6HHx) decreased as the 6HHx fraction increased.
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Affiliation(s)
- Yuka Hozumi
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, N13W8, Kitaku, Sapporo 060-8628, Japan
| | - Shin-Ichi Hachisuka
- Division of Applied Chemistry, Faculty of 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
| | - Hiroshi Kikukawa
- 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
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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.
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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.
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Zher Neoh S, Fey Chek M, Tiang Tan H, Linares-Pastén JA, Nandakumar A, Hakoshima T, Sudesh K. Polyhydroxyalkanoate synthase (PhaC): The key enzyme for biopolyester synthesis. CURRENT RESEARCH IN BIOTECHNOLOGY 2022. [DOI: 10.1016/j.crbiot.2022.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Lim H, Chuah JA, Chek MF, Tan HT, Hakoshima T, Sudesh K. Identification of regions affecting enzyme activity, substrate binding, dimer stabilization and polyhydroxyalkanoate (PHA) granule morphology in the PHA synthase of Aquitalea sp. USM4. Int J Biol Macromol 2021; 186:414-423. [PMID: 34246679 DOI: 10.1016/j.ijbiomac.2021.07.041] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 05/23/2021] [Accepted: 07/05/2021] [Indexed: 11/28/2022]
Abstract
Polyhydroxyalkanoates (PHAs) are biopolyesters synthesized by microorganisms as intracellular energy reservoirs under stressful environmental conditions. PHA synthase (PhaC) is the key enzyme responsible for PHA biosynthesis, but the importance of its N- and C-terminal ends still remains elusive. Six plasmid constructs expressing truncation variants of Aquitalea sp. USM4 PhaC (PhaC1As) were generated and heterologously expressed in Cupriavidus necator PHB-4. Removal of the first six residues at the N-terminus enabled the modulation of PHA composition without altering the PHA content in cells. Meanwhile, deletion of 13 amino acids from the C-terminus greatly affected the catalytic activity of PhaC1As, retaining only 1.1-7.4% of the total activity. Truncation(s) at the N- and/or C-terminus of PhaC1As gradually diminished the incorporation of comonomer units, and revealed that the N-terminal region is essential for PhaC1As dimerization whereas the C-terminal region is required for stabilization. Notably, transmission electron microscopy analysis showed that PhaC modification affected the morphology of intracellular PHA granules, which until now is only known to be regulated by phasins. This study provided substantial evidence and highlighted the significance of both the N- and C-termini of PhaC1As in regulating intracellular granule morphology, activity, substrate specificity, dimerization and stability of the synthase.
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Affiliation(s)
- Hui Lim
- Ecobiomaterial Research Laboratory, School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Jo-Ann Chuah
- Ecobiomaterial Research Laboratory, School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Min Fey Chek
- Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan
| | - Hua Tiang Tan
- Ecobiomaterial Research Laboratory, School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - 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 Penang, Malaysia.
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Li Y, Sun Z, Xu Y, Luan Y, Xu J, Liang Q, Qi Q, Wang Q. Enhancing the Glucose Flux of an Engineered EP-Bifido Pathway for High Poly(Hydroxybutyrate) Yield Production. Front Bioeng Biotechnol 2020; 8:517336. [PMID: 32984296 PMCID: PMC7481327 DOI: 10.3389/fbioe.2020.517336] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 08/12/2020] [Indexed: 11/25/2022] Open
Abstract
Background As the greenhouse effect becomes more serious and carbon dioxide emissions continue rise, the application prospects of carbon sequestration or carbon-saving pathways increase. Previously, we constructed an EP-bifido pathway in Escherichia coli by combining Embden-Meyerhof-Parnas pathway, pentose phosphate pathway and “bifid shunt” for high acetyl-CoA production. There is much room for improvement in the EP-bifido pathway, including in production of target compounds such as poly(hydroxybutyrate) (PHB). Result To optimize the EP-bifido pathway and obtain higher PHB yields, we knocked out the specific phosphoenolpyruvate phosphate transferase system (PTS) component II Cglc, encoded by ptsG. This severely inhibited the growth and sugar consumption of the bacterial cells. Subsequently, we used multiple automated genome engineering (MAGE) to optimize the ribosome binding site (RBS) sequences of galP (galactose: H (+) symporter) and glk (glucokinase gene bank: NC_017262.1), encoding galactose permease and glucokinase, respectively. Growth and glucose uptake were partially restored in the bacteria. Finally, we introduced the glf (UDP-galactopyranose) from Zymomonas mobilis mutase sugar transport vector into the host strain genome. Conclusion After optimizing RBS of galP, the resulting strain L-6 obtained a PHB yield of 71.9% (mol/mol) and a 76 wt% PHB content using glucose as the carbon source. Then when glf was integrated into the genome strain L-6, the resulting strain M-6 reached a 5.81 g/L PHB titer and 85.1 wt% PHB content.
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Affiliation(s)
- Ying Li
- National Glycoengineering Research Center, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Zhijie Sun
- Marine Biology Institute, Shantou University, Shantou, China
| | - Ya Xu
- National Glycoengineering Research Center, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yaqi Luan
- National Glycoengineering Research Center, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Jiasheng Xu
- National Glycoengineering Research Center, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Quanfeng Liang
- National Glycoengineering Research Center, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Qingsheng Qi
- National Glycoengineering Research Center, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China.,CAS Key Lab of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China
| | - Qian Wang
- National Glycoengineering Research Center, State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
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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.
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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
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Sagong HY, Son HF, Choi SY, Lee SY, Kim KJ. Structural Insights into Polyhydroxyalkanoates Biosynthesis. Trends Biochem Sci 2018; 43:790-805. [PMID: 30139647 DOI: 10.1016/j.tibs.2018.08.005] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Revised: 07/27/2018] [Accepted: 08/04/2018] [Indexed: 12/25/2022]
Abstract
Polyhydroxyalkanoates (PHAs) are diverse biopolyesters produced by numerous microorganisms and have attracted much attention as a substitute for petroleum-based polymers. Despite several decades of study, the detailed molecular mechanisms of PHA biosynthesis have remained unknown due to the lack of structural information on the key PHA biosynthetic enzyme PHA synthase. The recently determined crystal structure of PHA synthase, together with the structures of acetyl-coenzyme A (CoA) acetyltransferase and reductase, have changed this situation. Structural and biochemical studies provided important clues for the molecular mechanisms of each enzyme as well as the overall mechanism of PHA biosynthesis from acetyl-CoA. This new information and knowledge is expected to facilitate production of designed novel PHAs and also enhanced production of PHAs.
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Affiliation(s)
- Hye-Young Sagong
- School of Life Sciences, KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea; KNU Institute for Microorganisms, Kyungpook National University, Daegu 41566, Republic of Korea
| | - Hyeoncheol Francis Son
- School of Life Sciences, KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea; KNU Institute for Microorganisms, Kyungpook National University, Daegu 41566, Republic of Korea
| | - So Young Choi
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), BioProcess Engineering Research Center, Center for Systems and Synthetic Biotechnology, and Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), BioProcess Engineering Research Center, Center for Systems and Synthetic Biotechnology, and Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
| | - Kyung-Jin Kim
- School of Life Sciences, KNU Creative BioResearch Group, Kyungpook National University, Daegu 41566, Republic of Korea; KNU Institute for Microorganisms, Kyungpook National University, Daegu 41566, Republic of Korea.
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Zou H, Shi M, Zhang T, Li L, Li L, Xian M. Natural and engineered polyhydroxyalkanoate (PHA) synthase: key enzyme in biopolyester production. Appl Microbiol Biotechnol 2017; 101:7417-7426. [DOI: 10.1007/s00253-017-8485-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 08/07/2017] [Accepted: 08/10/2017] [Indexed: 01/30/2023]
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Kim YJ, Choi SY, Kim J, Jin KS, Lee SY, Kim KJ. Structure and function of the N-terminal domain of Ralstonia eutropha
polyhydroxyalkanoate synthase, and the proposed structure and mechanisms of the whole enzyme. Biotechnol J 2016; 12. [DOI: 10.1002/biot.201600649] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 10/31/2016] [Accepted: 11/02/2016] [Indexed: 11/09/2022]
Affiliation(s)
- Yeo-Jin Kim
- School of Life Sciences, KNU Creative BioResearch Group; Kyungpook National University; Daegu Republic of Korea
| | - So Young Choi
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), BioProcess Engineering Research Center, Center for Systems and Synthetic Biotechnology, and Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Jieun Kim
- School of Life Sciences, KNU Creative BioResearch Group; Kyungpook National University; Daegu Republic of Korea
| | - Kyeong Sik Jin
- Pohang Accelerator Laboratory; Pohang University of Science and Technology; Pohang Republic of Korea
| | - Sang Yup Lee
- Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), BioProcess Engineering Research Center, Center for Systems and Synthetic Biotechnology, and Institute for the BioCentury; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Kyung-Jin Kim
- School of Life Sciences, KNU Creative BioResearch Group; Kyungpook National University; Daegu Republic of Korea
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Agnew DE, Pfleger BF. Synthetic biology strategies for synthesizing polyhydroxyalkanoates from unrelated carbon sources. Chem Eng Sci 2013; 103:58-67. [DOI: 10.1016/j.ces.2012.12.023] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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