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Cai Y, Yu XH, Shanklin J. A toolkit for plant lipid engineering: Surveying the efficacies of lipogenic factors for accumulating specialty lipids. FRONTIERS IN PLANT SCIENCE 2022; 13:1064176. [PMID: 36589075 PMCID: PMC9795026 DOI: 10.3389/fpls.2022.1064176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Plants produce energy-dense lipids from carbohydrates using energy acquired via photosynthesis, making plant oils an economically and sustainably attractive feedstock for conversion to biofuels and value-added bioproducts. A growing number of strategies have been developed and optimized in model plants, oilseed crops and high-biomass crops to enhance the accumulation of storage lipids (mostly triacylglycerols, TAGs) for bioenergy applications and to produce specialty lipids with increased uses and value for chemical feedstock and nutritional applications. Most successful metabolic engineering strategies involve heterologous expression of lipogenic factors that outperform those from other sources or exhibit specialized functionality. In this review, we summarize recent progress in engineering the accumulation of triacylglycerols containing - specialized fatty acids in various plant species and tissues. We also provide an inventory of specific lipogenic factors (including accession numbers) derived from a wide variety of organisms, along with their reported efficacy in supporting the accumulation of desired lipids. A review of previously obtained results serves as a foundation to guide future efforts to optimize combinations of factors to achieve further enhancements to the production and accumulation of desired lipids in a variety of plant tissues and species.
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Affiliation(s)
- Yingqi Cai
- Biology Department, Brookhaven National Laboratory, Upton, NY, United States
| | - Xiao-Hong Yu
- Biology Department, Brookhaven National Laboratory, Upton, NY, United States
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, United States
| | - John Shanklin
- Biology Department, Brookhaven National Laboratory, Upton, NY, United States
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2
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Colin-Oviedo Á, Garza-Aguilar SM, Marín-Obispo LM, Rodríguez-Sánchez DG, Trevino V, Hernández-Brenes C, Díaz de la Garza RI. The Enigmatic Aliphatic Acetogenins and Their Correlations With Lipids During Seed Germination and Leaf Development of Avocado ( Persea americana Mill.). FRONTIERS IN PLANT SCIENCE 2022; 13:839326. [PMID: 35592561 PMCID: PMC9111537 DOI: 10.3389/fpls.2022.839326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 03/16/2022] [Indexed: 06/15/2023]
Abstract
Lipids in avocados have been widely studied due to their nutritional value and several reported bioactivities. Aliphatic acetogenins are a relevant component of the avocado lipidome and have been tested for several potential food and pharma industries applications. This work followed the evolution of avocado fatty acids (FAs) and aliphatic acetogenins during seed germination and leaf growth. Oil extracts of embryonic axes, cotyledons, and leaves from seedlings and trees were divided to analyze free acetylated acetogenins (AcO-acetogenins), and free FAs. Embryonic axes from germinating seeds contained the highest amount of AcO-acetogenins and FAs; this tissue also accumulated the most diverse FA profile with up to 22 detected moieties. Leaves presented the highest variations in AcO-acetogenin profiles during development, although leaves from seedlings accumulated the simplest FA profile with only 10 different FAs. Remarkably, AcO-acetogenins represented half of the carbons allocated to lipids in grown leaves, while embryonic axes and cotyledons always contained more carbons within FAs during germination. Thus, we hypothesized the use of the AcO-acetogenin acyl chain for energy production toward β-oxidation. Also, α-linolenic and docosahexaenoic acids (DHAs) were proposed as close AcO-acetogenin intermediaries based on a correlation network generated using all these data. Another part of the oil extract was fractionated into different lipid classes before transesterification to profile FAs and acetogenins bound to lipids. Acetogenin backbones were identified for the first time in triglycerides from cotyledons and mainly in polar lipids (which include phospholipids) in all developing avocado tissues analyzed. Seed tissues accumulated preferentially polar lipids during germination, while triglycerides were consumed in cotyledons. Seedling leaves contained minute amounts of triglycerides, and polar lipids increased as they developed. Results from this work suggest acetogenins might be part of the energy and signaling metabolisms, and possibly of membrane structures, underlining the yet to establish role(s) of these unusual lipids in the avocado plant physiology.
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Affiliation(s)
- Álvaro Colin-Oviedo
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Monterrey, Mexico
| | | | | | | | - Víctor Trevino
- Tecnologico de Monterrey, The Institute for Obesity Research, Integrative Biology Unit, Monterrey, Mexico
- Tecnologico de Monterrey, Escuela de Medicina, Monterrey, Mexico
| | - Carmen Hernández-Brenes
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Monterrey, Mexico
- Tecnologico de Monterrey, The Institute for Obesity Research, Integrative Biology Unit, Monterrey, Mexico
| | - Rocío I. Díaz de la Garza
- Tecnologico de Monterrey, Escuela de Ingeniería y Ciencias, Monterrey, Mexico
- Tecnologico de Monterrey, The Institute for Obesity Research, Integrative Biology Unit, Monterrey, Mexico
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Klińska S, Jasieniecka-Gazarkiewicz K, Demski K, Banaś A. Editing of phosphatidic acid and phosphatidylethanolamine by acyl-CoA: lysophospholipid acyltransferases in developing Camelina sativa seeds. PLANTA 2020; 252:4. [PMID: 32524208 PMCID: PMC7286856 DOI: 10.1007/s00425-020-03408-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 05/22/2020] [Indexed: 06/11/2023]
Abstract
The main source of polyunsaturated acyl-CoA in cytoplasmic acyl-CoA pool of Camelina sativa seeds are fatty acids derived from phosphatidylcholine followed by phosphatidic acid. Contribution of phosphatidylethanolamine is negligible. While phosphatidylethanolamine (PE) is the second most abundant phospholipid, phosphatidic acid (PA) only constitutes a small fraction of C. sativa seeds' polar lipids. In spite of this, the relative contribution of PA in providing fatty acids for the synthesis of acyl-CoA, supplying cytosolic acyl-CoA pool seems to be much higher than the contribution of PE. Our data indicate that up to 5% of fatty acids present in mature C. sativa seeds are first esterified with PA, in comparison to 2% first esterified with PE, before being transferred into acyl-CoA pool via backward reactions of either acyl-CoA:lysophosphatidic acid acyltransferases (CsLPAATs) or acyl-CoA:lysophoshatidylethanolamine acyltransferases (CsLPEATs). Those acyl-CoAs are later reused for lipid biosynthesis or remodelling. In the forward reactions both aforementioned acyltransferases display the highest activity at 30 °C. The spectrum of optimal pH differs for both enzymes with CsLPAATs most active between pH 7.5-9.0 and CsLPEATs between pH 9.0 to 10.0. Whereas addition of magnesium ions stimulates CsLPAATs, calcium and potassium ions inhibit them in concentrations of 0.05-2.0 mM. All three types of ions inhibit CsLPEATs activity. Both tested acyltransferases present the highest preferences towards 16:0-CoA and unsaturated 18-carbon acyl-CoAs in forward reactions. However, CsLPAATs preferentially utilise 18:1-CoA and CsLPEATs preferentially utilise 18:2-CoA while catalysing fatty acid remodelling of PA and PE, respectively.
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Affiliation(s)
- Sylwia Klińska
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland
| | | | - Kamil Demski
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland
| | - Antoni Banaś
- Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland
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Maghuly F, Deák T, Vierlinger K, Pabinger S, Tafer H, Laimer M. Gene expression profiling identifies pathways involved in seed maturation of Jatropha curcas. BMC Genomics 2020; 21:290. [PMID: 32272887 PMCID: PMC7146973 DOI: 10.1186/s12864-020-6666-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 03/11/2020] [Indexed: 11/10/2022] Open
Abstract
Background Jatropha curcas, a tropical shrub, is a promising biofuel crop, which produces seeds with high content of oil and protein. To better understand the maturation process of J. curcas seeds and to improve its agronomic performance, a two-step approach was performed in six different maturation stages of seeds: 1) generation of the entire transcriptome of J. curcas seeds using 454-Roche sequencing of a cDNA library, 2) comparison of transcriptional expression levels using a custom Agilent 8x60K oligonucleotide microarray. Results A total of 793,875 high-quality reads were assembled into 19,382 unique full-length contigs, of which 13,507 could be annotated with Gene Ontology (GO) terms. Microarray data analysis identified 9111 probes (out of 57,842 probes), which were differentially expressed between the six maturation stages. The expression results were validated for 75 selected transcripts based on expression levels, predicted function, pathway, and length. Result from cluster analyses showed that transcripts associated with fatty acid, flavonoid, and phenylpropanoid biosynthesis were over-represented in the early stages, while those of lipid storage were over-represented in the late stages. Expression analyses of different maturation stages of J. curcas seed showed that most changes in transcript abundance occurred between the two last stages, suggesting that the timing of metabolic pathways during seed maturation in J. curcas occurs in late stages. The co-expression results showed that the hubs (CB5-D, CDR1, TT8, DFR, HVA22) with the highest number of edges, associated with fatty acid and flavonoid biosynthesis, are showing a decrease in their expression during seed maturation. Furthermore, seed development and hormone pathways are significantly well connected. Conclusion The obtained results revealed differentially expressed sequences (DESs) regulating important pathways related to seed maturation, which could contribute to the understanding of the complex regulatory network during seed maturation with the focus on lipid, flavonoid and phenylpropanoid biosynthesis. This study provides detailed information on transcriptional changes during J. curcas seed maturation and provides a starting point for a genomic survey of seed quality traits. The results highlighted specific genes and processes relevant to the molecular mechanisms involved in Jatropha seed maturation. These data can also be utilized regarding other Euphorbiaceae species.
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Affiliation(s)
- Fatemeh Maghuly
- Plant Functional Genomics, Department of Biotechnology, BOKU-VIBT, University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria.
| | - Tamás Deák
- Department of Viticulture, Szent István University, Villányi út 29-43, 1118 Budapest, Hungary
| | - Klemens Vierlinger
- Center for Health and Bioresources, Molecular Diagnostics, Austrian Institute of Technology (AIT), Giefinggasse 4, 1210, Vienna, Austria
| | - Stephan Pabinger
- Center for Health and Bioresources, Molecular Diagnostics, Austrian Institute of Technology (AIT), Giefinggasse 4, 1210, Vienna, Austria
| | - Hakim Tafer
- Austrian Center of Biological Resources (ACBR), Department of Biotechnology, BOKU-VIBT, University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria
| | - Margit Laimer
- Plant Biotechnology Unit, Department of Biotechnology, BOKU-VIBT, University of Natural Resources and Life Sciences, Muthgasse 18, 1190, Vienna, Austria
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Jasieniecka-Gazarkiewicz K, Demski K, Lager I, Stymne S, Banaś A. Possible Role of Different Yeast and Plant Lysophospholipid:Acyl-CoA Acyltransferases (LPLATs) in Acyl Remodelling of Phospholipids. Lipids 2015; 51:15-23. [PMID: 26643989 PMCID: PMC4700060 DOI: 10.1007/s11745-015-4102-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 11/12/2015] [Indexed: 12/02/2022]
Abstract
Recent results have suggested that plant lysophosphatidylcholine:acyl-coenzyme A acyltransferases (LPCATs) can operate in reverse in vivo and thereby catalyse an acyl exchange between the acyl-coenzyme A (CoA) pool and the phosphatidylcholine. We have investigated the abilities of Arabidopsis AtLPCAT2, Arabidopsis lysophosphatidylethanolamine acyltransferase (LPEAT2), S. cerevisiae lysophospholipid acyltransferase (Ale1) and S. cerevisiae lysophosphatidic acid acyltransferase (SLC1) to acylate lysoPtdCho, lysoPtdEtn and lysoPtdOH and act reversibly on the products of the acylation; the PtdCho, PtdEtn and PtdOH. The tested LPLATs were expressed in an S. cervisiaeale1 strain and enzyme activities were assessed in assays using microsomal preparations of the different transformants. The results show that, despite high activity towards lysoPtdCho, lysoPtdEtn and lysoPtdOH by the ALE1, its capacities to operate reversibly on the products of the acylation were very low. Slc1 readily acylated lysoPtdOH, lysoPtdCho and lysoPtdEtn but showed no reversibility towards PtdCho, very little reversibility towards PtdEtn and very high reversibility towards PtdOH. LPEAT2 showed the highest levels of reversibility towards PtdCho and PtdEtn of all LPLATs tested but low ability to operate reversibly on PtdOH. AtLPCAT2 showed good reversible activity towards PtdCho and PtdEtn and very low reversibility towards PtdOH. Thus, it appears that some of the LPLATs have developed properties that, to a much higher degree than other LPLATs, promote the reverse reaction during the same assay conditions and with the same phospholipid. The results also show that the capacity of reversibility can be specific for a particular phospholipid, albeit the lysophospholipid derivatives of other phospholipids serve as good acyl acceptors for the forward reaction of the enzyme.
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Affiliation(s)
| | - Kamil Demski
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Kładki 24, 80-822, Gdańsk, Poland
| | - Ida Lager
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53, Alnarp, Sweden
| | - Sten Stymne
- Department of Plant Breeding, Swedish University of Agricultural Sciences, 230 53, Alnarp, Sweden
| | - Antoni Banaś
- Intercollegiate Faculty of Biotechnology, University of Gdańsk and Medical University of Gdańsk, Kładki 24, 80-822, Gdańsk, Poland.
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Sumner LW, Lei Z, Nikolau BJ, Saito K. Modern plant metabolomics: advanced natural product gene discoveries, improved technologies, and future prospects. Nat Prod Rep 2015; 32:212-29. [PMID: 25342293 DOI: 10.1039/c4np00072b] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Plant metabolomics has matured and modern plant metabolomics has accelerated gene discoveries and the elucidation of a variety of plant natural product biosynthetic pathways. This review covers the approximate period of 2000 to 2014, and highlights specific examples of the discovery and characterization of novel genes and enzymes associated with the biosynthesis of natural products such as flavonoids, glucosinolates, terpenoids, and alkaloids. Additional examples of the integration of metabolomics with genome-based functional characterizations of plant natural products that are important to modern pharmaceutical technology are also reviewed. This article also provides a substantial review of recent technical advances in mass spectrometry imaging, nuclear magnetic resonance imaging, integrated LC-MS-SPE-NMR for metabolite identifications, and X-ray crystallography of microgram quantities for structural determinations. The review closes with a discussion on the future prospects of metabolomics related to crop species and herbal medicine.
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Affiliation(s)
- Lloyd W Sumner
- The Samuel Roberts Noble Foundation, Plant Biology Division, 2510 Sam Noble Parkway, Ardmore, OK, USA.
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7
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Lager I, Yilmaz JL, Zhou XR, Jasieniecka K, Kazachkov M, Wang P, Zou J, Weselake R, Smith MA, Bayon S, Dyer JM, Shockey JM, Heinz E, Green A, Banas A, Stymne S. Plant acyl-CoA:lysophosphatidylcholine acyltransferases (LPCATs) have different specificities in their forward and reverse reactions. J Biol Chem 2013; 288:36902-14. [PMID: 24189065 PMCID: PMC3873549 DOI: 10.1074/jbc.m113.521815] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Acyl-CoA:lysophosphatidylcholine acyltransferase (LPCAT) enzymes have central roles in acyl editing of phosphatidylcholine (PC). Plant LPCAT genes were expressed in yeast and characterized biochemically in microsomal preparations of the cells. Specificities for different acyl-CoAs were similar for seven LPCATs from five different species, including species accumulating hydroxylated acyl groups in their seed oil, with a preference for C18-unsaturated acyl-CoA and low activity with palmitoyl-CoA and ricinoleoyl (12-hydroxyoctadec-9-enoyl)-CoA. We showed that Arabidopsis LPCAT1 and LPCAT2 enzymes catalyzed the acylation and de-acylation of both sn positions of PC, with a preference for the sn-2 position. When acyl specificities of the Arabidopsis LPCATs were measured in the reverse reaction, sn-2-bound oleoyl, linoleoyl, and linolenoyl groups from PC were transferred to acyl-CoA to a similar extent. However, a ricinoleoyl group at the sn-2-position of PC was removed 4–6-fold faster than an oleoyl group in the reverse reaction, despite poor utilization in the forward reaction. The data presented, taken together with earlier published reports on in vivo lipid metabolism, support the hypothesis that plant LPCAT enzymes play an important role in regulating the acyl-CoA composition in plant cells by transferring polyunsaturated and hydroxy fatty acids produced on PC directly to the acyl-CoA pool for further metabolism or catabolism.
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Affiliation(s)
- Ida Lager
- From the Department of Plant Breeding, Swedish University of Agricultural Sciences, S-230 53 Alnarp, Sweden
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Hur M, Campbell AA, Almeida-de-Macedo M, Li L, Ransom N, Jose A, Crispin M, Nikolau BJ, Wurtele ES. A global approach to analysis and interpretation of metabolic data for plant natural product discovery. Nat Prod Rep 2013; 30:565-83. [PMID: 23447050 PMCID: PMC3629923 DOI: 10.1039/c3np20111b] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Discovering molecular components and their functionality is key to the development of hypotheses concerning the organization and regulation of metabolic networks. The iterative experimental testing of such hypotheses is the trajectory that can ultimately enable accurate computational modelling and prediction of metabolic outcomes. This information can be particularly important for understanding the biology of natural products, whose metabolism itself is often only poorly defined. Here, we describe factors that must be in place to optimize the use of metabolomics in predictive biology. A key to achieving this vision is a collection of accurate time-resolved and spatially defined metabolite abundance data and associated metadata. One formidable challenge associated with metabolite profiling is the complexity and analytical limits associated with comprehensively determining the metabolome of an organism. Further, for metabolomics data to be efficiently used by the research community, it must be curated in publicly available metabolomics databases. Such databases require clear, consistent formats, easy access to data and metadata, data download, and accessible computational tools to integrate genome system-scale datasets. Although transcriptomics and proteomics integrate the linear predictive power of the genome, the metabolome represents the nonlinear, final biochemical products of the genome, which results from the intricate system(s) that regulate genome expression. For example, the relationship of metabolomics data to the metabolic network is confounded by redundant connections between metabolites and gene-products. However, connections among metabolites are predictable through the rules of chemistry. Therefore, enhancing the ability to integrate the metabolome with anchor-points in the transcriptome and proteome will enhance the predictive power of genomics data. We detail a public database repository for metabolomics, tools and approaches for statistical analysis of metabolomics data, and methods for integrating these datasets with transcriptomic data to create hypotheses concerning specialized metabolisms that generate the diversity in natural product chemistry. We discuss the importance of close collaborations among biologists, chemists, computer scientists and statisticians throughout the development of such integrated metabolism-centric databases and software.
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Affiliation(s)
- Manhoi Hur
- Human Computer Interactions and Department of Genetics Development and Cell Biology, 2624 Howe Hall, Iowa State University, Ames, IA 50011, USA. Fax: +1 515 294 0803; Tel: +1 515 708 3232;
| | - Alexis Ann Campbell
- Biochemistry, Biophysics and Molecular Biology and Center for Biorenewable Chemicals and Center for Metabolic Biology, 3254 Molecular Biology Building, Iowa State University, Ames, IA 50010, USA. Fax: +1 515 294 9423; Tel: +1 515 294 0453;
| | - Marcia Almeida-de-Macedo
- Department of Genetics Development and Cell Biology, 2624 Howe Hall, Iowa State University, Ames, IA 50011, USA. Fax: +1 515 294 5530; Tel: +1 515 294 3738;
| | - Ling Li
- Department of Genetics Development and Cell Biology, 443 Bessey Hall Iowa State University, Ames, IA 50011, USA. Fax: +1 515 294 1337; Tel: +1 515 294 6236;
| | - Nick Ransom
- Department of Genetics Development and Cell Biology, 2624 Howe Hall, Iowa State University, Ames, IA 50011, USA. Fax: +1 515 294 0803; Tel: +1 515 708 3232;
| | - Adarsh Jose
- Bioinformatics and Computational Biology, Center for Biorenewable Chemicals, Iowa State University, Ames, IA 50010, USA. Fax: +1 515 294 1269; Tel: +1 515 230 3429;
| | - Matt Crispin
- Department of Genetics Development and Cell Biology, 443 Bessey Hall Iowa State University, Ames, IA 50011, USA. Fax: +1 515 294 1337; Tel: +1 515 294 6236;
| | - Basil J. Nikolau
- Biochemistry, Biophysics and Molecular Biology and Center for Biorenewable Chemicals and Center for Metabolic Biology, 3254 Molecular Biology Building, Iowa State University, Ames, IA 50010, USA. Fax: +1 515 294 9423; Tel: +1 515 294 0453;
| | - Eve Syrkin Wurtele
- Department of Genetics, Development and Cell Biology, Center for Metabolic Biology, and Center for Biorenewable Chemicals, 2624D Howe Hall, Iowa State University, Ames, IA 50011, USA. Fax: +1 515 294 0803; Tel: +1 515 708 3232;
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Blée E, Flenet M, Boachon B, Fauconnier ML. A non-canonical caleosin fromArabidopsisefficiently epoxidizes physiological unsaturated fatty acids with complete stereoselectivity. FEBS J 2012; 279:3981-95. [DOI: 10.1111/j.1742-4658.2012.08757.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Revised: 08/15/2012] [Accepted: 08/16/2012] [Indexed: 11/29/2022]
Affiliation(s)
- Elizabeth Blée
- Institut de Biologie Moléculaire des Plantes; Université de Strasbourg; France
| | - Martine Flenet
- Institut de Biologie Moléculaire des Plantes; Université de Strasbourg; France
| | - Benoît Boachon
- Institut de Biologie Moléculaire des Plantes; Université de Strasbourg; France
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10
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Probing substrate–product relationships by natural abundance deuterium 2D NMR spectroscopy in liquid-crystalline solvents: epoxidation of linoleate to vernoleate by two different plant enzymes. Anal Bioanal Chem 2012; 402:2985-98. [DOI: 10.1007/s00216-012-5748-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 01/12/2012] [Accepted: 01/13/2012] [Indexed: 11/25/2022]
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11
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Li R, Yu K, Wu Y, Tateno M, Hatanaka T, Hildebrand DF. Vernonia DGATs can complement the disrupted oil and protein metabolism in epoxygenase-expressing soybean seeds. Metab Eng 2012; 14:29-38. [PMID: 22107928 DOI: 10.1016/j.ymben.2011.11.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Revised: 10/31/2011] [Accepted: 11/02/2011] [Indexed: 11/21/2022]
Abstract
Plant oils can be useful chemical feedstocks such as a source of epoxy fatty acids. High seed-specific expression of a Stokesia laevis epoxygenase (SlEPX) in soybeans only results in 3-7% epoxide levels. SlEPX-transgenic soybean seeds also exhibited other phenotypic alterations, such as altered seed fatty acid profiles, reduced oil accumulation, and variable protein levels. SlEPX-transgenic seeds showed a 2-5% reduction in total oil content and protein levels of 30.9-51.4%. To address these pleiotrophic effects of SlEPX expression on other traits, transgenic soybeans were developed to co-express SlEPX and DGAT (diacylglycerol acyltransferase) genes (VgDGAT1 & 2) isolated from Vernonia galamensis, a high accumulator of epoxy fatty acids. These side effects of SlEPX expression were largely overcome in the DGAT co-expressing soybeans. Total oil and protein contents were restored to the levels in non-transgenic soybeans, indicating that both VgDGAT1 and VgDGAT2 could complement the disrupted phenotypes caused by over-expression of an epoxygenase in soybean seeds.
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Affiliation(s)
- Runzhi Li
- Department of Plant and Soil Science, University of Kentucky, KY 40546-0312, USA
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12
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Cagliari A, Margis R, Dos Santos Maraschin F, Turchetto-Zolet AC, Loss G, Margis-Pinheiro M. Biosynthesis of Triacylglycerols (TAGs) in plants and algae. INTERNATIONAL JOURNAL OF PLANT BIOLOGY 2011. [DOI: 10.4081/pb.2011.e10] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Triacylglycerols (TAGs), which consist of three fatty acids bound to a glycerol backbone, are major storage lipids that accumulate in developing seeds, flower petals, pollen grains, and fruits of innumerous plant species. These storage lipids are of great nutritional and nutraceutical value and, thus, are a common source of edible oils for human consumption and industrial purposes. Two metabolic pathways for the production of TAGs have been clarified: an acyl¬ CoA-dependent pathway and an acyl-CoA-independent pathway. Lipid metabolism, specially the pathways to fatty acids and TAG biosynthesis, is relatively well understood in plants, but poorly known in algae. It is generally accepted that the basic pathways of fatty acid and TAG biosynthesis in algae are analogous to those of higher plants. However, unlike higher plants where individual classes of lipids may be synthesized and localized in a specific cell, tissue or organ, the complete pathway, from carbon dioxide fixation to TAG synthesis and sequestration, takes place within a single algal cell. Another distinguishing feature of some algae is the large amounts of very long-chain polyunsaturated fatty acids (VLC- PUFAs) as major fatty acid components. Nowadays, the focus of attention in biotechnology is the isolation of novel fatty acid metabolizing genes, especially elongases and desaturases that are responsible for PUFAs synthesis, from different species of algae, and its transfer to plants. The aim is to boost the seed oil content and to generate desirable fatty acids in oilseed crops through genetic engineering approaches. This paper presents the current knowledge of the neutral storage lipids in plants and algae from fatty acid biosynthesis to TAG accumulation.
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Li R, Yu K, Hatanaka T, Hildebrand DF. Vernonia DGATs increase accumulation of epoxy fatty acids in oil. PLANT BIOTECHNOLOGY JOURNAL 2010; 8:184-95. [PMID: 20078841 DOI: 10.1111/j.1467-7652.2009.00476.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Vernolic acid (cis-12-epoxy-octadeca-cis-9-enoic acid) is valuable as a renewable chemical feedstock. This fatty acid can accumulate to high levels in the seed oil of some plant species such as Vernonia galamensis and Stokesia laevis which are unsuitable for large-scale production. A cost-effective alternative for production of epoxy fatty acids is to genetically engineer its biosynthesis in commercial oilseeds. An epoxygenase cDNA (SlEPX) responsible for vernolic acid synthesis and two acyl-CoA : diacylglycerol acyltransferase cDNAs (VgDGAT1 and VgDGAT2) catalysing triacylglycerol (TAG) formation were cloned from developing seeds of S. laevis and V. galamensis. Co-expression of SlEPX and VgDGAT1 or VgDGAT2 greatly increases accumulation of vernolic acid both in petunia leaves and soybean somatic embryos. Seed-specific expression of VgDGAT1 and VgDGAT2 in SlEPX mature soybean seeds results in vernolic acid levels of approximately 15% and 26%. Both DGAT1 and DGAT2 increase epoxy fatty acid accumulation with DGAT2 having much greater impact.
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Affiliation(s)
- Runzhi Li
- Department of Plant and Soil Science, University of Kentucky, Lexington, KY, USA
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14
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Li R, Yu K, Hildebrand DF. DGAT1, DGAT2 and PDAT expression in seeds and other tissues of epoxy and hydroxy fatty acid accumulating plants. Lipids 2010; 45:145-57. [PMID: 20101470 DOI: 10.1007/s11745-010-3385-4] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Accepted: 01/01/2010] [Indexed: 10/19/2022]
Abstract
Triacylglycerol (TAG) is the main storage lipid in plants. Acyl-CoA: diacylglycerol acyltransferase (DGAT1 and DGAT2) and phospholipid: diacylglycerol acyltransferase (PDAT) can catalyze TAG synthesis. It is unclear how these three independent genes are regulated in developing seeds, and particularly if they have specific functions in the high accumulation of unusual fatty acids in seed oil. The expression patterns of DGAT1, DGAT2 and a PDAT in relation to the accumulation of oil and epoxy and hydroxy fatty acids in developing seeds of the plant species Vernonia galamensis, Euphorbia lagascae, Stokesia laevis and castor that accumulate high levels of these fatty acids in comparison with soybean and Arabidopsis were investigated. The expression patterns of DGAT1, DGAT2 and the PDAT are consistent with all three enzymes playing a role in the high epoxy or hydroxy fatty acid accumulation in developing seeds of these plants. PDAT and DGAT2 transcript levels are present at much higher levels in developing seeds of epoxy and hydroxy fatty acid accumulating plants than in soybeans or Arabidopsis. Moreover, PDAT, DGAT1 and DGAT2 are found to be expressed in many different plant tissues, suggesting that these enzymes may have other roles in addition to seed oil accumulation. DGAT1 appears to be a major enzyme for seed oil accumulation at least in Arabidopsis and soybeans. For the epoxy and hydroxy fatty acid accumulating plants, DGAT2 and PDAT also show expression patterns consistent with a role in the selective accumulation of these unusual fatty acids in seed oil.
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Affiliation(s)
- Runzhi Li
- Department of Plant and Soil Science, University of Kentucky, Lexington, KY 40546, USA
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15
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Compagnon V, Diehl P, Benveniste I, Meyer D, Schaller H, Schreiber L, Franke R, Pinot F. CYP86B1 is required for very long chain omega-hydroxyacid and alpha, omega -dicarboxylic acid synthesis in root and seed suberin polyester. PLANT PHYSIOLOGY 2009; 150:1831-43. [PMID: 19525321 PMCID: PMC2719127 DOI: 10.1104/pp.109.141408] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Accepted: 05/27/2009] [Indexed: 05/18/2023]
Abstract
Suberin composition of various plants including Arabidopsis (Arabidopsis thaliana) has shown the presence of very long chain fatty acid derivatives C20 in addition to the C16 and C18 series. Phylogenetic studies and plant genome mining have led to the identification of putative aliphatic hydroxylases belonging to the CYP86B subfamily of cytochrome P450 monooxygenases. In Arabidopsis, this subfamily is represented by CYP86B1 and CYP86B2, which share about 45% identity with CYP86A1, a fatty acid omega-hydroxylase implicated in root suberin monomer synthesis. Here, we show that CYP86B1 is located to the endoplasmic reticulum and is highly expressed in roots. Indeed, CYP86B1 promoter-driven beta-glucuronidase expression indicated strong reporter activities at known sites of suberin production such as the endodermis. These observations, together with the fact that proteins of the CYP86B type are widespread among plant species, suggested a role of CYP86B1 in suberin biogenesis. To investigate the involvement of CYP86B1 in suberin biogenesis, we characterized an allelic series of cyp86B1 mutants of which two strong alleles were knockouts and two weak ones were RNA interference-silenced lines. These root aliphatic plant hydroxylase lines had a root and a seed coat aliphatic polyester composition in which C22- and C24-hydroxyacids and alpha,omega-dicarboxylic acids were strongly reduced. However, these changes did not affect seed coat permeability and ion content in leaves. The presumed precursors, C22 and C24 fatty acids, accumulated in the suberin polyester. These results demonstrate that CYP86B1 is a very long chain fatty acid hydroxylase specifically involved in polyester monomer biosynthesis during the course of plant development.
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Affiliation(s)
- Vincent Compagnon
- Institut de Biologie Moléculaire des Plantes, CNRS-Université Louis Pasteur Unité Propre de Recherche 2357, Département Réseaux Métaboliques Végétaux, F-67083 Strasbourg cedex, France
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16
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The biosynthesis of cutin and suberin as an alternative source of enzymes for the production of bio-based chemicals and materials. Biochimie 2009; 91:685-91. [DOI: 10.1016/j.biochi.2009.03.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2009] [Accepted: 03/25/2009] [Indexed: 11/18/2022]
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17
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Matos AR, Pham-Thi AT. Lipid deacylating enzymes in plants: old activities, new genes. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2009; 47:491-503. [PMID: 19324564 DOI: 10.1016/j.plaphy.2009.02.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2008] [Revised: 02/18/2009] [Accepted: 02/20/2009] [Indexed: 05/01/2023]
Abstract
Because lipids are major components of cellular membranes, their degradation under stress conditions compromises compartmentalization. However, in addition to having structural roles, membrane lipids are also implicated in signalling processes involving the activity of lipolytic enzymes. Phospholipases D and C, acting on the polar heads of phospholipids, have been relatively well characterized in plants. In contrast, knowledge of lipid deacylating enzymes remains limited. Lipid acyl hydrolases (LAH) are able to hydrolyse both fatty acid moieties of polar lipids. They differ from phospholipases A(1) or A(2) (PLA) acting on sn-1 or sn-2 positions of phospholipids, respectively, as well as from lipases which de-esterify triacylglycerols. The free polyunsaturated fatty acids generated by deacylating enzymes can be used in the biosynthesis of oxylipins and the lysophospholipids, provided by PLAs, are also bioactive molecules. In the four decades that have passed since the first description of LAH activities in plants some enzymes have been purified. In recent years, the widespread use of molecular approaches together with the attention paid to lipid signalling has contributed to a renewed interest in LAH and has led to the identification of different gene families and the characterization of new enzymes. Additionally, several proteins with putative lipase/esterase signatures have been identified. In the present paper we review currently available data on LAHs, PLAs, triacylglycerol lipases and other putative deacylating enzymes. The roles of lipid deacylating enzymes in plant growth, development and stress responses are discussed in the context of their involvement in membrane deterioration, lipid turnover and cellular signalling.
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Affiliation(s)
- Ana Rita Matos
- Centro de Engenharia Biológica, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, Lisboa, Portugal.
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18
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Hatanaka T, Yu K, Li R, Hildebrand D. Accumulation of Epoxy Fatty Acids in Plant Oils. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2009. [DOI: 10.1201/9781420077070.ch3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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19
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Sauveplane V, Kandel S, Kastner PE, Ehlting J, Compagnon V, Werck-Reichhart D, Pinot F. Arabidopsis thaliana CYP77A4 is the first cytochrome P450 able to catalyze the epoxidation of free fatty acids in plants. FEBS J 2008; 276:719-35. [PMID: 19120447 DOI: 10.1111/j.1742-4658.2008.06819.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An approach based on an in silico analysis predicted that CYP77A4, a cytochrome P450 that so far has no identified function, might be a fatty acid-metabolizing enzyme. CYP77A4 was heterologously expressed in a Saccharomyces cerevisiae strain (WAT11) engineered for cytochrome P450 expression. Lauric acid (C(12:0)) was converted into a mixture of hydroxylauric acids when incubated with microsomes from yeast expressing CYP77A4. A variety of physiological C(18) fatty acids were tested as potential substrates. Oleic acid (cis-Delta(9)C(18:1)) was converted into a mixture of omega-4- to omega-7-hydroxyoleic acids (75%) and 9,10-epoxystearic acid (25%). Linoleic acid (cis,cis-Delta(9),Delta(12)C(18:2)) was exclusively converted into 12,13-epoxyoctadeca-9-enoic acid, which was then converted into diepoxide after epoxidation of the Delta(9) unsaturation. Chiral analysis showed that 9,10-epoxystearic acid was a mixture of 9S/10R and 9R/10S in the ratio 33 : 77, whereas 12,13-epoxyoctadeca-9-enoic acid presented a strong enantiomeric excess in favor of 12S/13R, which represented 90% of the epoxide. Neither stearic acid (C(18:0)) nor linolelaidic acid (trans,trans-Delta(9),Delta(12)C(18:2)) was metabolized, showing that CYP77A4 requires a double bond, in the cis configuration, to metabolize C(18) fatty acids. CYP77A4 was also able to catalyze the in vitro formation of the three mono-epoxides of alpha-linolenic acid (cis,cis,cis-Delta(9),Delta(12),Delta(15)C(18:3)), previously described as antifungal compounds. Epoxides generated by CYP77A4 are further metabolized to the corresponding diols by epoxide hydrolases located in microsomal and cytosolic subcellular fractions from Arabidopsis thaliana. The concerted action of CYP77A4 with epoxide hydrolases and hydroxylases allows the production of compounds involved in plant-pathogen interactions, suggesting a possible role for CYP77A4 in plant defense.
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Affiliation(s)
- Vincent Sauveplane
- Institut de Biologie Moléculaire des Plantes, University of Strasbourg, France
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20
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Lesot P, Baillif V, Billault I. Combined Analysis of C-18 Unsaturated Fatty Acids Using Natural Abundance Deuterium 2D NMR Spectroscopy in Chiral Oriented Solvents. Anal Chem 2008; 80:2963-72. [DOI: 10.1021/ac702443b] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Philippe Lesot
- Université de Paris-Sud (XI), ICMMO, UMR CNRS 8182, Laboratoire de Chimie Structurale Organique, Equipe de RMN en Milieu Orienté, UFR des sciences d'Orsay, Bât. 410, 91405 Orsay Cedex, France, and Université de Nantes, CEISAM, Chimie Et Interdisciplinarité, Synthèse, Analyse, Modélisation, UMR CNRS 6230, UFR des Sciences et des Techniques, 2, rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France
| | - Vincent Baillif
- Université de Paris-Sud (XI), ICMMO, UMR CNRS 8182, Laboratoire de Chimie Structurale Organique, Equipe de RMN en Milieu Orienté, UFR des sciences d'Orsay, Bât. 410, 91405 Orsay Cedex, France, and Université de Nantes, CEISAM, Chimie Et Interdisciplinarité, Synthèse, Analyse, Modélisation, UMR CNRS 6230, UFR des Sciences et des Techniques, 2, rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France
| | - Isabelle Billault
- Université de Paris-Sud (XI), ICMMO, UMR CNRS 8182, Laboratoire de Chimie Structurale Organique, Equipe de RMN en Milieu Orienté, UFR des sciences d'Orsay, Bât. 410, 91405 Orsay Cedex, France, and Université de Nantes, CEISAM, Chimie Et Interdisciplinarité, Synthèse, Analyse, Modélisation, UMR CNRS 6230, UFR des Sciences et des Techniques, 2, rue de la Houssinière, BP 92208, 44322 Nantes Cedex 3, France
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21
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Yu K, Li R, Hatanaka T, Hildebrand D. Cloning and functional analysis of two type 1 diacylglycerol acyltransferases from Vernonia galamensis. PHYTOCHEMISTRY 2008; 69:1119-27. [PMID: 18179805 DOI: 10.1016/j.phytochem.2007.11.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Revised: 11/17/2007] [Accepted: 11/26/2007] [Indexed: 05/12/2023]
Abstract
Vernonia galamensis accumulates vernolic acid (cis-12-epoxyoctadeca-cis-9-enoic acid) as the major fatty acid in its seed oil. Such epoxy fatty acids are useful in a number of industrial applications. Successful genetic engineering of commercial oilseed crops to produce high levels of vernolic acid depends on a better understanding of the source plant enzymes for vernolic acid accumulation. Developing V. galamensis seed microsome assays demonstrate that diacylglycerol acyltransferase (DGAT), an enzyme for the final step of triacylglycerol synthesis, has a strong substrate preference for vernolic acid bearing substrates including acyl-CoA and diacylglycerol. There are two classes of DGATs known as DGAT1 and DGAT2. Here we report on the isolation, characterization, and functional analysis of two DGAT1 cDNAs from V. galamensis (VgDGAT1a and VgDGAT1b). VgDGAT1a and VgDGAT1b are expressed in all plant tissues examined with highest expression in developing seeds. Enzymatic assays using isolated microsomes from transformed yeast show that VgDGAT1a and VgDGAT1b have the same DGAT activity levels and substrate specificities. Oleoyl-CoA and sn-1,2-dioleoylglycerol are preferred substrates over vernoloyl-CoA and sn-1,2-divernoloylglycerol. This data indicates that the two VgDGAT1s are functional, but not likely to be responsible for the selective accumulation of vernolic acid in V. galamensis seed oil.
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Affiliation(s)
- Keshun Yu
- Department of Plant and Soil Science, University of Kentucky, 1405 Veterans Drive, Lexington, KY 40546-0091, USA
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22
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Duarte N, Kayser O, Abreu P, Ferreira MJU. Antileishmanial activity of piceatannol isolated fromEuphorbia lagascae seeds. Phytother Res 2008; 22:455-7. [DOI: 10.1002/ptr.2334] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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23
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Salas JJ, Moreno-Pérez AJ, Martínez-Force E, Garcés R. Characterization of the glycerolipid composition of a high-palmitoleic acid sunflower mutant. EUR J LIPID SCI TECH 2007. [DOI: 10.1002/ejlt.200600285] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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24
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Yu K, McCracken CT, Li R, Hildebrand DF. Diacylglycerol acyltransferases from Vernonia and Stokesia prefer substrates with vernolic acid. Lipids 2006; 41:557-66. [PMID: 16981434 DOI: 10.1007/s11745-006-5005-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Genetic engineering of common oil crops for industrially valuable epoxy FA production by expressing epoxygenase genes alone had limited success. Identifying other key genes responsible for the selective incorporation of epoxy FA into seed oil in natural high accumulators appears to be an important next step. We investigated the substrate preferences of acyl CoA:diacylglycerol acyltransferases (DGAT) of two natural high accumulators of vernolic acid, Vernonia galamensis and Stokesia laevis, as compared with a common oilseed crop soybean. Developing seed microsomes were fed with either [14C]oleoyl CoA or [14C] vernoloyl CoA in combinations with no exogenous DAG or with 1,2-dioleoyl-sn-glycerol, 1-palmitoyl-2-vernoloyl-sn-glycerol, 1,2-divernoloyl-sn-glycerol, 1,2-dioleoyl-rac-glycerol, or 1,2-divernoloyl-rac-glycerol to determine their relative incorporation into TAG. The results showed that in using sn-1,2-DAG, the highest DGAT activity was from the substrate combination of vernoloyl CoA with 1,2-divernoloyl-sn-glycerol, and the lowest was from vernoloyl CoA or oleoyl CoA with 1,2-dioleoyl-sn-glycerol in both V. galamensis and S. laevis. Soybean DGAT was more active with oleoyl CoA than vernoloyl CoA, and more active with 1,2-dioleoyl-sn-glycerol when oleoyl CoA was fed. DGAT assays without exogenous DAG, or with exogenous sn-1,2-DAG fed individually or simultaneously showed consistent results. In combinations with either oleoyl CoA or vernoloyl CoA, DGAT had much higher activity with rac-1,2-DAG than with their corresponding sn-1,2-DAG, and the substrate selectivity was diminished when rac-1,2-DAG were used instead of sn-1,2-DAG. These studies suggest that DGAT action might be an important step for selective incorporation of vernolic acid into TAG in V. galamensis and S. laevis.
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Affiliation(s)
- Keshun Yu
- Department of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky 40546, USA
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25
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Cahoon EB, Kinney AJ. The production of vegetable oils with novel properties: Using genomic tools to probe and manipulate plant fatty acid metabolism. EUR J LIPID SCI TECH 2005. [DOI: 10.1002/ejlt.200590020] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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26
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Billault I, Duan JR, Guiet S, Robins RJ. Quantitative deuterium isotopic profiling at natural abundance indicates mechanistic differences for delta 12-epoxidase and delta 12-desaturase in Vernonia galamensis. J Biol Chem 2005; 280:17645-51. [PMID: 15722338 DOI: 10.1074/jbc.m500909200] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Quantitative (2)H NMR spectroscopy can determine the natural abundance ((2)H/(1)H) ratio at each site of a molecule. In natural products, variation in these values is related to the reaction mechanisms in the pertinent biosynthetic pathway. For the first time, this novel approach has been exploited to probe for mechanistic differences in the introduction of different functionalities into a long-chain fatty acid. Vernolic acid, a major component of the seed oil of Vernonia galamensis, contains both an epoxide and a desaturation. The site-specific isotopic distribution ((2)H/(1)H)(i) has been determined for both vernolic acid and linoleic acid isolated from the same V. galamensis oil. It is found that the ((2)H/(1)H) ratio of vernolic acid shows a pattern along the entire length of the chain, consistent with linoleic acid being its immediate precursor. Notably, the C13 relates to the C13 of linoleic acid but not to the C13 of oleic acid. Furthermore, the C12 and C13 positions in vernolic acid are less depleted, consistent with a change in hybridization state from sp(2) to sp(3). However, the C11 position shows a marked relative enrichment in the vernolic acid, implying that it plays a role in the epoxidase but not the desaturase mechanism. Thus, although it can be concluded that the catalytic mechanisms for the epoxidase and desaturase activities are similar, marked differences in the residual ((2)H/(1)H) patterns indicate that the reaction mechanisms are not identical.
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Affiliation(s)
- Isabelle Billault
- Groupe de Fractionnement Isotopique de Métabolismes, Laboratoire d'Analyse Isotopique et Electrochimique de Métabolismes, CNRS UMR6006, Université de Nantes, BP 99208, F-44322 Nantes, France.
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27
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Newman JW, Morisseau C, Hammock BD. Epoxide hydrolases: their roles and interactions with lipid metabolism. Prog Lipid Res 2005; 44:1-51. [PMID: 15748653 DOI: 10.1016/j.plipres.2004.10.001] [Citation(s) in RCA: 320] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The epoxide hydrolases (EHs) are enzymes present in all living organisms, which transform epoxide containing lipids by the addition of water. In plants and animals, many of these lipid substrates have potent biologically activities, such as host defenses, control of development, regulation of inflammation and blood pressure. Thus the EHs have important and diverse biological roles with profound effects on the physiological state of the host organisms. Currently, seven distinct epoxide hydrolase sub-types are recognized in higher organisms. These include the plant soluble EHs, the mammalian soluble epoxide hydrolase, the hepoxilin hydrolase, leukotriene A4 hydrolase, the microsomal epoxide hydrolase, and the insect juvenile hormone epoxide hydrolase. While our understanding of these enzymes has progressed at different rates, here we discuss the current state of knowledge for each of these enzymes, along with a distillation of our current understanding of their endogenous roles. By reviewing the entire enzyme class together, both commonalities and discrepancies in our understanding are highlighted and important directions for future research pertaining to these enzymes are indicated.
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Affiliation(s)
- John W Newman
- Department of Entomology, UCDavis Cancer Center, University of California, One Shields Avenue, Davis, CA 95616, USA
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28
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Cahoon EB, Ripp KG, Hall SE, McGonigle B. Transgenic production of epoxy fatty acids by expression of a cytochrome P450 enzyme from Euphorbia lagascae seed. PLANT PHYSIOLOGY 2002; 128:615-24. [PMID: 11842164 PMCID: PMC148923 DOI: 10.1104/pp.010768] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2001] [Revised: 10/24/2001] [Accepted: 10/31/2001] [Indexed: 05/18/2023]
Abstract
Seed oils of a number of Asteraceae and Euphorbiaceae species are enriched in 12-epoxyoctadeca-cis-9-enoic acid (vernolic acid), an unusual 18-carbon Delta(12)-epoxy fatty acid with potential industrial value. It has been previously demonstrated that the epoxy group of vernolic acid is synthesized by the activity of a Delta(12)-oleic acid desaturase-like enzyme in seeds of the Asteraceae Crepis palaestina and Vernonia galamensis. In contrast, results from metabolic studies have suggested the involvement of a cytochrome P450 enzyme in vernolic acid synthesis in seeds of the Euphorbiaceae species Euphorbia lagascae. To clarify the biosynthetic origin of vernolic acid in E. lagascae seed, an expressed sequence tag analysis was conducted. Among 1,006 randomly sequenced cDNAs from developing E. lagascae seeds, two identical expressed sequence tags were identified that encode a cytochrome P450 enzyme classified as CYP726A1. Consistent with the seed-specific occurrence of vernolic acid in E. lagascae, mRNA corresponding to the CYP726A1 gene was abundant in developing seeds, but was not detected in leaves. In addition, expression of the E. lagascae CYP726A1 cDNA in Saccharomyces cerevisiae was accompanied by production of vernolic acid in cultures supplied with linoleic acid and an epoxy fatty acid tentatively identified as 12-epoxyoctadeca-9,15-dienoic acid (12-epoxy-18:2Delta(9,15)) in cultures supplied with alpha-linolenic acid. Consistent with this, expression of CYP726A1 in transgenic tobacco (Nicotiana tabacum) callus or somatic soybean (Glycine max) embryos resulted in the accumulation of vernolic acid and 12-epoxy-18:2Delta(9,15). Overall, these results conclusively demonstrate that Asteraceae species and the Euphorbiaceae E. lagascae have evolved structurally unrelated enzymes to generate the Delta(12)-epoxy group of vernolic acid.
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Affiliation(s)
- Edgar B Cahoon
- DuPont Crop Genetics, Experimental Station, Wilmington, DE 19880-0402, USA.
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29
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Voelker T, Kinney AJ. VARIATIONS IN THE BIOSYNTHESIS OF SEED-STORAGE LIPIDS. ANNUAL REVIEW OF PLANT PHYSIOLOGY AND PLANT MOLECULAR BIOLOGY 2001; 52:335-361. [PMID: 11337402 DOI: 10.1146/annurev.arplant.52.1.335] [Citation(s) in RCA: 164] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In many plants lipids represent up to 80% of dry weight of storage tissues. In seeds, lipids accumulate as triacylglycerols (TAGs), which are formed by an extension of the membrane-lipid biosynthetic pathway common to all plant tissues. In contrast to the conserved fatty acid (FA) composition of membrane lipids, the observed divergence in seed oil acyl chains among different species is very high. The acyl groups of seed TAGs can vary in their chain length (from 8 to 24) as well as in their degree of unsaturation. In addition to methylene-interrupted double bonds, many seeds contain TAGs that have unusual functional groups in their FAs, such as hydroxyl, oxirane, or acetylene groups. All of the major steps in the biosynthetic pathway to TAG are now known and sequence information for genes encoding most of the enzymes involved is available. Here we present the current knowledge of the metabolic mechanisms involved in the divergence from the membrane-lipid biosynthetic pathway during storage lipid formation.
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Affiliation(s)
- Toni Voelker
- Monsanto Corporation, Calgene Campus, 1920 Fifth Street, Davis, California 95691; e-mail: , Dupont Nutrition and Health, Experimental Station, P. O. Box 80402, Wilmington, Delaware 19880-0402; e-mail:
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30
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Greene JF, Williamson KC, Newman JW, Morisseau C, Hammock BD. Metabolism of monoepoxides of methyl linoleate: bioactivation and detoxification. Arch Biochem Biophys 2000; 376:420-32. [PMID: 10775430 DOI: 10.1006/abbi.2000.1753] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Leukotoxin (ltx) and isoleukotoxin (iltx) methyl esters, are metabolites of methyl linoleic acid, an essential fatty acid. They have been associated with acute respiratory distress syndrome. The observed toxicity of ltx and iltx is, in fact, due to the metabolism of the epoxides to their corresponding diols by soluble epoxide hydrolase (sEH). Herein, we demonstrate that ltx/iltx are toxic in a time-dependent manner to human sEH expressing cells with a LT(50) of 10.6 +/- 0.8 h and that ltx and iltx have K(M) of 6.15 +/- 1.0 and 5. 17 +/- 0.56 microM, respectively, and V(max) of 2.67 +/- 0.04 and 1. 86 +/- 0.06 micromol/min/mg, respectively, which can be inhibited by sEH inhibitors. We show that four major metabolites of ltx/iltx are formed in our system, including ltx/iltx free acid, ltxd/iltxd, free acid, and phosphotidylcholine and phosphotidylethanolamine containing the carboxylic acid forms of both ltx/iltx and ltxd/iltxd, but that the only metabolite associated with toxicity is the carboxylic acid form of ltxd/iltxd, suggesting the involvement of cellular esterases. We demonstrate that a serine esterase inhibitor provides some protection from the toxicity of epoxy fatty esters to sEH expressing cells as do intercellular free sulfhydryls, but that this protection is not due to glutathione conjugation. With these data, we have proposed an extension of the metabolic pathway for ltx/iltx in eukaryotic cells.
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Affiliation(s)
- J F Greene
- Department of Entomology, University of California at Davis, Davis, California 95616, USA
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31
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Liu L, Hammond EG, Nikolau BJ. In vivo studies of the biosynthesis of vernolic acid in the seed of Vernonia galamensis. Lipids 1998; 33:1217-21. [PMID: 9930408 DOI: 10.1007/s11745-998-0326-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In vivo radiotracer experiments using [1-(14C)]acetate as the precursor were conducted to investigate the biosynthesis of vernolic acid (12, 13-epoxy-cis-9-octadecenoic acid) in the seeds of Vernonia galamensis. The acetate precursor radioactively labeled vernolate in phosphatidylcholine (PC), diacylglycerol, and triacylglycerol. Time-course kinetics of the incorporation of the radioactive tracer indicated that vernolate is synthesized while the acyl moiety is esterified to PC. Pulse-chase experiments provided additional supporting evidence that vernolate is synthesized while esterified to PC. These results are consistent with the hypothesis that linoleoyl PC is the precursor of vernoleoyl-PC. Subsequently, vernolate is quickly moved from the PC pool to the triacylglycerol pool, where it accumulates.
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Affiliation(s)
- L Liu
- Department of Food Science and Human Nutrition, Iowa State University, Ames 50011, USA
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32
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Affiliation(s)
- A Grechkin
- Institute of Biology, Russian Academy of Sciences, Kazan, Russia
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33
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Abstract
Desaturation of a fatty acid first involves the enzymatic removal of a hydrogen from a methylene group in an acyl chain, a highly energy-demanding step that requires an activated oxygen intermediate. Two types of desaturases have been identified, one soluble and the other membrane-bound, that have different consensus motifs. Database searching for these motifs reveals that these enzymes belong to two distinct multifunctional classes, each of which includes desaturases, hydroxylases, and epoxidases that act on fatty acids or other substrates. The soluble class has a consensus motif consisting of carboxylates and histidines that coordinate an active site diiron cluster. The integral membrane class contains a different consensus motif composed of histidines. Biochemical and structural similarities between the integral membrane enzymes suggest that this class also uses a diiron cluster for catalysis. Soluble and membrane enzymes have been successfully re-engineered for substrate specificity and reaction outcome. It is anticipated that rational design of these enzymes will result in new and desired activities that may form the basis for improved oil crops.
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Affiliation(s)
- John Shanklin
- Department of Biology, Brookhaven National Laboratory, Upton, New York 11973; e-mail:
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34
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Tijet N, Helvig C, Pinot F, Le Bouquin R, Lesot A, Durst F, Salaün JP, Benveniste I. Functional expression in yeast and characterization of a clofibrate-inducible plant cytochrome P-450 (CYP94A1) involved in cutin monomers synthesis. Biochem J 1998; 332 ( Pt 2):583-9. [PMID: 9601090 PMCID: PMC1219516 DOI: 10.1042/bj3320583] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The chemical tagging of a cytochrome P-450-dependent lauric acid omega-hydroxylase from clofibrate-treated Vicia sativa seedlings with [1-14C]11-dodecynoic acid allowed the isolation of a full-length cDNA designated CYP94A1. We describe here the functional expression of this novel P-450 in two Saccharomyces cerevisiae strains overproducing their own NADPH-cytochrome P-450 reductase or a reductase from Arabidopsis thaliana. The results show a much higher efficiency of the yeast strain overproducing the plant reductase compared with the yeast strain overproducing its own reductase for expressing CYP94A1. The methyl end of saturated (from C-10 to C-16) and unsaturated (C18:1, C18:2 and C18:3) fatty acids was mainly oxidized by CYP94A1. Both E/Z and Z/E configurations of 9, 12-octadecadienoic acids were omega-hydroxylated. Lauric, myristic and linolenic acids were oxidized with the highest turnover rate (24 min-1). The strong regioselectivity of CYP94A1 was clearly shifted with sulphur-containing substrates, since both 9- and 11-thia laurate analogues were sulphoxidized. Similar to animal omega-hydroxylases, this plant enzyme was strongly induced by clofibrate treatment. Rapid CYP94A1 transcript accumulation was detected less than 20 min after exposure of seedlings to the hypolipidaemic drug. The involvement of CYP94A1 in the synthesis of cutin monomers and fatty acid detoxification is discussed.
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Affiliation(s)
- N Tijet
- Institut de Biologie Moléculaire des Plantes-CNRS, Département d'Enzymologie Cellulaire et Moléculaire, 28 rue Goethe, F-67083 Strasbourg Cedex, France
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35
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Lee M, Lenman M, Banaś A, Bafor M, Singh S, Schweizer M, Nilsson R, Liljenberg C, Dahlqvist A, Gummeson PO, Sjödahl S, Green A, Stymne S. Identification of non-heme diiron proteins that catalyze triple bond and epoxy group formation. Science 1998; 280:915-8. [PMID: 9572738 DOI: 10.1126/science.280.5365.915] [Citation(s) in RCA: 207] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Acetylenic bonds are present in more than 600 naturally occurring compounds. Plant enzymes that catalyze the formation of the Delta12 acetylenic bond in 9-octadecen-12-ynoic acid and the Delta12 epoxy group in 12,13-epoxy-9-octadecenoic acid were characterized, and two genes, similar in sequence, were cloned. When these complementary DNAs were expressed in Arabidopsis thaliana, the content of acetylenic or epoxidated fatty acids in the seeds increased from 0 to 25 or 15 percent, respectively. Both enzymes have characteristics similar to the membrane proteins containing non-heme iron that have histidine-rich motifs.
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Affiliation(s)
- M Lee
- Svalöv-Weibull AB, S-268 81 Svalöv, Sweden
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36
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Ståhl U, Ek B, Stymne S. Purification and characterization of a low-molecular-weight phospholipase A2 from developing seeds of elm. PLANT PHYSIOLOGY 1998; 117:197-205. [PMID: 9576789 PMCID: PMC35004 DOI: 10.1104/pp.117.1.197] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/1997] [Accepted: 02/06/1998] [Indexed: 05/22/2023]
Abstract
Phospholipase A2 (PLA2) was purified about 180,000 times compared with the starting soluble-protein extract from developing elm (Ulmus glabra) seeds. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis the purified fraction showed a single protein band with a mobility that corresponded to 15 kD, from which activity could be recovered. When analyzed by matrix-assisted laser-desorption ionization-time-of-flight mass spectrometry, the enzyme had a deduced mass of 13,900 D. A 53-amino acid-long N-terminal sequence was determined and aligned with other sequences, giving 62% identity to the deduced amino acid sequence of some rice (Oryza sativa) expressed sequence tag clones. The purified enzyme had an alkaline pH optimum and required Ca2+ for activity. It was unusually stable with regard to heat, acidity, and organic solvents but was sensitive to disulfide bond-reducing agents. The enzyme is a true PLA2, neither hydrolyzing the sn-1 position of phosphatidylcholine nor having any activity toward lysophosphatidylcholine or diacylglycerol. The biochemical data and amino acid sequence alignments indicate that the enzyme is related to the well-characterized family of animal secretory PLA2s and, to our knowledge, is the first plant enzyme of this type to be described.
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Affiliation(s)
- U Ståhl
- Department of Plant Biology, P.O. Box 7080, Swedish University of Agricultural Sciences, S-750 07 Uppsala, Sweden.
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37
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Benveniste I, Tijet N, Adas F, Philipps G, Salaün JP, Durst F. CYP86A1 from Arabidopsis thaliana encodes a cytochrome P450-dependent fatty acid omega-hydroxylase. Biochem Biophys Res Commun 1998; 243:688-93. [PMID: 9500987 DOI: 10.1006/bbrc.1998.8156] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The A. thaliana EST database was screened using consensus motifs derived from P450 families CYP52 and CYP4 catalyzing the omega-hydroxylation of fatty acids and alkanes in Candida and in mammals. One EST cDNA fragment was detected in this way and the corresponding full-length cDNA was cloned from a cDNA library of A. thaliana. This cDNA coded the first member of a new plant P450 family and was termed CYP86A1. The deduced peptide sequence showed highest homology with P450s from families 4 and 52. To confirm the catalytic function, CYP86A1 was expressed in a yeast overexpressing its own NADPH-P450 reductase. Efficient expression was evidenced by spectrophotometry, SDS-PAGE and catalytic activity. CYP86A1 was found to catalyze the omega-hydroxylation of saturated and unsaturated fatty acids with chain lengths from C12 to C18 but not of hexadecane. Genomic organization analyzed by Southern blot suggested a single gene encoding CYP86A1 in A. thaliana.
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Affiliation(s)
- I Benveniste
- Institut de Biologie Moléculaire des Plantes-CNRS, Département d'Enzymologie Cellulaire et Moléculaire, Strasbourg, France.
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38
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Abstract
Jasmonic acid and its derivatives can modulate aspects of fruit ripening, production of viable pollen, root growth, tendril coiling, and plant resistance to insects and pathogens. Jasmonate activates genes involved in pathogen and insect resistance, and genes encoding vegetative storage proteins, but represses genes encoding proteins involved in photosynthesis. Jasmonic acid is derived from linolenic acid, and most of the enzymes in the biosynthetic pathway have been extensively characterized. Modulation of lipoxygenase and allene oxide synthase gene expression in transgenic plants raises new questions about the compartmentation of the biosynthetic pathway and its regulation. The activation of jasmonic acid biosynthesis by cell wall elicitors, the peptide systemin, and other compounds will be related to the function of jasmonates in plants. Jasmonate modulates gene expression at the level of translation, RNA processing, and transcription. Promoter elements that mediate responses to jasmonate have been isolated. This review covers recent advances in our understanding of how jasmonate biosynthesis is regulated and relates this information to knowledge of jasmonate modulated gene expression.
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Affiliation(s)
- Robert A. Creelman
- Department of Biochemistry and Biophysics, Crop Biotechnology Center, Texas A&M University, College Station, Texas 77843
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39
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Abstract
This review discusses fatty acid modification of oilseeds with additional emphasis on production of oxygenated derivatives. In a relatively short period, less than a decade, our understanding of the enzymes involved in plant fatty acid synthesis has increased to the point where we understand how they might be used in oilseed modification. Further, through modern molecular biological techniques, the actual genes for many of these important enzymes have been cloned. Use of genetic transformation systems has allowed us to fundamentally alter the normal biosynthetic pathways in highly specific ways, in manners that would be either difficult or impossible using traditional breeding techniques. Alteration of plant lipid biosynthesis is not restricted to using genes from the plants themselves, but interspecies transfer is possible, either from completely unrelated plant species (often of no commercial value but possessing unusual biochemical properties) or from animals, fungi, and prokaryotic organisms. In this way "designer" plants possessing altered metabolism, tailored to the interests or needs of certain industries, nutritionists, and the consumer can be created.
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Affiliation(s)
- G J Budziszewski
- Department of Agronomy, University of Kentucky, Lexington 40546, USA
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40
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Salaün JP, Helvig C. Cytochrome P450-dependent oxidation of fatty acids. DRUG METABOLISM AND DRUG INTERACTIONS 1995; 12:261-83. [PMID: 8820856 DOI: 10.1515/dmdi.1995.12.3-4.261] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Cytochrome P450-dependent monooxygenases from plants catalyse in-chain and omega hydroxylation as well as epoxidation of medium- and long-chain fatty acids. Recent research efforts have clarified that there are multiple forms of cytochrome P450 involved in these reactions, each of which possesses distinguishable substrate specificity. The biological roles of these distinct P450 forms are poorly understood. However, evidence suggests that some may play an important role in the biosynthesis of plant cuticles. We review current knowledge on the induction and inhibition of activities as well as the regio- and stereo-specificity of the distinct forms so far characterised.
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Affiliation(s)
- J P Salaün
- Département d'Enzymologie Cellulaire et Moléculaire, Institut de Biologie Moléculaire des Plantes, CNRS-UPR 406, Strasbourg, France
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41
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Abstract
The present status of plant cytochrome P450 research is reviewed. A comparison of the properties of this group of cytochrome proteins with those of other microsomal b-type haem proteins is made. The range of reactions catalysed by P450s is discussed as well as recent progress in improving purification and reconstitution. Molecular cloning approaches that have overcome the earlier block to accessing this gene superfamily are discussed and future prospects highlighted. Expression of the gene family is discussed in relation to regulation in response to environmental and developmental cues and tissue and subcellular localization. The biotechnological importance of this gene family is stressed.
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Affiliation(s)
- G P Bolwell
- Department of Biochemistry, Royal Holloway and Bedford New College, University of London, Egham, Surrey, U.K
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