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Kalinger RS, Rowland O. Determinants of substrate specificity in a catalytically diverse family of acyl-ACP thioesterases from plants. BMC PLANT BIOLOGY 2023; 23:1. [PMID: 36588156 PMCID: PMC9806908 DOI: 10.1186/s12870-022-04003-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 12/13/2022] [Indexed: 05/05/2023]
Abstract
BACKGROUND ACYL-LIPID THIOESTERASES (ALTs) are a subclass of plastid-localized, fatty acyl-acyl carrier protein (ACP) thioesterase enzymes from plants. They belong to the single hot dog-fold protein family. ALT enzymes generate medium-chain (C6-C14) and C16 fatty acids, methylketone precursors (β-keto fatty acids), and 3-hydroxy fatty acids when expressed heterologously in E. coli. The diverse substrate chain-length and oxidation state preferences of ALTs set them apart from other plant acyl-ACP thioesterases, and ALTs show promise as metabolic engineering tools to produce high-value medium-chain fatty acids and methylketones in bacterial or plant systems. Here, we used a targeted motif-swapping approach to explore connections between ALT protein sequence and substrate specificity. Guided by comparative motif searches and computational modelling, we exchanged regions of amino acid sequence between ALT-type thioesterases from Arabidopsis thaliana, Medicago truncatula, and Zea mays to create chimeric ALT proteins. RESULTS Comparing the activity profiles of chimeric ALTs in E. coli to their wild-type counterparts led to the identification of interacting regions within the thioesterase domain that shape substrate specificity and enzyme activity. Notably, the presence of a 31-CQH[G/C]RH-36 motif on the central α-helix was shown to shift chain-length specificity towards 12-14 carbon chains, and to be a core determinant of substrate specificity in ALT-type thioesterases with preference for 12-14 carbon 3-hydroxyacyl- and β-ketoacyl-ACP substrates. For an ALT containing this motif to be functional, an additional 108-KXXA-111 motif and compatible sequence spanning aa77-93 of the surrounding β-sheet must also be present, demonstrating that interactions between residues in these regions of the catalytic domain are critical to thioesterase activity. The behaviour of chimeric enzymes in E. coli also indicated that aa77-93 play a significant role in dictating whether an ALT will prefer ≤10-carbon or ≥ 12-carbon acyl chain-lengths, and aa91-96 influence selectivity for substrates of fully or partially reduced oxidation states. Additionally, aa64-67 on the hot dog-fold β-sheet were shown to be important for enabling an ALT to act on 3-hydroxy fatty acyl-ACP substrates. CONCLUSIONS By revealing connections between thioesterase sequence and substrate specificity, this study is an advancement towards engineering recombinant ALTs with product profiles suited for specific applications.
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Affiliation(s)
- Rebecca S Kalinger
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada
| | - Owen Rowland
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada.
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Caswell BT, de Carvalho CC, Nguyen H, Roy M, Nguyen T, Cantu DC. Thioesterase enzyme families: Functions, structures, and mechanisms. Protein Sci 2022; 31:652-676. [PMID: 34921469 PMCID: PMC8862431 DOI: 10.1002/pro.4263] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 12/11/2021] [Accepted: 12/14/2021] [Indexed: 12/12/2022]
Abstract
Thioesterases are enzymes that hydrolyze thioester bonds in numerous biochemical pathways, for example in fatty acid synthesis. This work reports known functions, structures, and mechanisms of updated thioesterase enzyme families, which are classified into 35 families based on sequence similarity. Each thioesterase family is based on at least one experimentally characterized enzyme, and most families have enzymes that have been crystallized and their tertiary structure resolved. Classifying thioesterases into families allows to predict tertiary structures and infer catalytic residues and mechanisms of all sequences in a family, which is particularly useful because the majority of known protein sequence have no experimental characterization. Phylogenetic analysis of experimentally characterized thioesterases that have structures with the two main structural folds reveal convergent and divergent evolution. Based on tertiary structure superimposition, catalytic residues are predicted.
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Affiliation(s)
- Benjamin T. Caswell
- Department of Chemical and Materials EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - Caio C. de Carvalho
- Department of Chemical and Materials EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - Hung Nguyen
- Department of Computer Science and EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - Monikrishna Roy
- Department of Computer Science and EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - Tin Nguyen
- Department of Computer Science and EngineeringUniversity of Nevada, RenoRenoNevadaUSA
| | - David C. Cantu
- Department of Chemical and Materials EngineeringUniversity of Nevada, RenoRenoNevadaUSA
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Qi P, Pendergast TH, Johnson A, Bahri BA, Choi S, Missaoui A, Devos KM. Quantitative trait locus mapping combined with variant and transcriptome analyses identifies a cluster of gene candidates underlying the variation in leaf wax between upland and lowland switchgrass ecotypes. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2021; 134:1957-1975. [PMID: 33760937 PMCID: PMC8263549 DOI: 10.1007/s00122-021-03798-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 02/19/2021] [Indexed: 06/06/2023]
Abstract
Mapping combined with expression and variant analyses in switchgrass, a crop with complex genetics, identified a cluster of candidate genes for leaf wax in a fast-evolving region of chromosome 7K. Switchgrass (Panicum virgatum L.) is a promising warm-season candidate energy crop. It occurs in two ecotypes, upland and lowland, which vary in a number of phenotypic traits, including leaf glaucousness. To initiate trait mapping, two F2 mapping populations were developed by crossing two different F1 sibs derived from a cross between the tetraploid lowland genotype AP13 and the tetraploid upland genotype VS16, and high-density linkage maps were generated. Quantitative trait locus (QTL) analyses of visually scored leaf glaucousness and of hydrophobicity of the abaxial leaf surface measured using a drop shape analyzer identified highly significant colocalizing QTL on chromosome 7K (Chr07K). Using a multipronged approach, we identified a cluster of genes including Pavir.7KG077009, which encodes a Type III polyketide synthase-like protein, and Pavir.7KG013754 and Pavir.7KG030500, two highly similar genes that encode putative acyl-acyl carrier protein (ACP) thioesterases, as strong candidates underlying the QTL. The lack of homoeologs for any of the three genes on Chr07N, the relatively low level of identity with other switchgrass KCS proteins and thioesterases, as well as the organization of the surrounding region suggest that Pavir.7KG077009 and Pavir.7KG013754/Pavir.7KG030500 were duplicated into a fast-evolving chromosome region, which led to their neofunctionalization. Furthermore, sequence analyses showed all three genes to be absent in the two upland compared to the two lowland accessions analyzed. This study provides an example of and practical guide for trait mapping and candidate gene identification in a complex genetic system by combining QTL mapping, transcriptomics and variant analysis.
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Affiliation(s)
- Peng Qi
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
- Institute of Plant Breeding, Genetics and Genomics, and Department of Crop and Soil Sciences, University of Georgia, Athens, GA, 30602, USA
| | - Thomas H Pendergast
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
- Institute of Plant Breeding, Genetics and Genomics, and Department of Crop and Soil Sciences, University of Georgia, Athens, GA, 30602, USA
| | - Alex Johnson
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
| | - Bochra A Bahri
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
- Institute of Plant Breeding, Genetics and Genomics, and Department of Crop and Soil Sciences, University of Georgia, Athens, GA, 30602, USA
- Department of Plant Pathology, University of Georgia, Griffin, GA, 30223, USA
| | - Soyeon Choi
- Department of Genetics, University of Georgia, Athens, GA, 30602, USA
| | - Ali Missaoui
- Institute of Plant Breeding, Genetics and Genomics, and Department of Crop and Soil Sciences, University of Georgia, Athens, GA, 30602, USA
| | - Katrien M Devos
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA.
- Institute of Plant Breeding, Genetics and Genomics, and Department of Crop and Soil Sciences, University of Georgia, Athens, GA, 30602, USA.
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Kalinger RS, Williams D, Ahmadi Pirshahid A, Pulsifer IP, Rowland O. Production of C6-C14 Medium-Chain Fatty Acids in Seeds and Leaves via Overexpression of Single Hotdog-Fold Acyl-Lipid Thioesterases. Lipids 2021; 56:327-344. [PMID: 33547664 DOI: 10.1002/lipd.12299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/29/2020] [Accepted: 01/14/2021] [Indexed: 11/07/2022]
Abstract
ACYL-LIPID THIOESTERASES (ALT) are a type of plant acyl-acyl carrier protein thioesterase that generate a wide range of medium-chain fatty acids and methylketone (MK) precursors when expressed heterologously in Escherichia coli. While this makes ALT-type thioesterases attractive as metabolic engineering targets to increase production of high-value medium-chain fatty acids and MKs in plant systems, the behavior of ALT enzymes in planta was not well understood before this study. To profile the substrate specificities of ALT-type thioesterases in different plant tissue types, AtALT1-4 from Arabidopsis thaliana, which have widely varied chain length and oxidation state preferences in E. coli, were overexpressed in Arabidopsis seeds, Camelina sativa seeds, and Nicotiana benthamiana leaves. Seed-specific overexpression of ALT enzymes led to medium-chain fatty acid accumulation in Arabidopsis and Camelina seed triacylglycerols, and transient overexpression in N. benthamiana demonstrated that the substrate preferences of ALT-type thioesterases in planta generally agree with those previously determined in E. coli. AtALT1 and AtALT4 overexpression in leaves and seeds resulted in the accumulation of 12-14 carbon-length fatty acids and 6-8 carbon-length fatty acids, respectively. While it was difficult to completely profile the products of ALT-type thioesterases that generate MK precursors (i.e. β-keto fatty acids), our results nonetheless demonstrate that ALT enzymes are catalytically diverse in planta. The knowledge gained from this study is a significant step towards being able to use ALT-type thioesterases as metabolic engineering tools to modify the fatty acid profiles of oilseed crops, other plants, and microorganisms.
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Affiliation(s)
- Rebecca S Kalinger
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada
| | - Danielle Williams
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada
| | - Ali Ahmadi Pirshahid
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada
| | - Ian P Pulsifer
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada
| | - Owen Rowland
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada
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Kalinger RS, Pulsifer IP, Hepworth SR, Rowland O. Fatty Acyl Synthetases and Thioesterases in Plant Lipid Metabolism: Diverse Functions and Biotechnological Applications. Lipids 2020; 55:435-455. [PMID: 32074392 DOI: 10.1002/lipd.12226] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 01/29/2020] [Accepted: 01/30/2020] [Indexed: 11/09/2022]
Abstract
Plants use fatty acids to synthesize acyl lipids for many different cellular, physiological, and defensive roles. These roles include the synthesis of essential membrane, storage, or surface lipids, as well as the production of various fatty acid-derived metabolites used for signaling or defense. Fatty acids are activated for metabolic processing via a thioester linkage to either coenzyme A or acyl carrier protein. Acyl synthetases metabolically activate fatty acids to their thioester forms, and acyl thioesterases deactivate fatty acyl thioesters to free fatty acids by hydrolysis. These two enzyme classes therefore play critical roles in lipid metabolism. This review highlights the surprisingly complex and varying roles of fatty acyl synthetases in plant lipid metabolism, including roles in the intracellular trafficking of fatty acids. This review also surveys the many specialized fatty acyl thioesterases characterized to date in plants, which produce a great diversity of fatty acid products in a tissue-specific manner. While some acyl thioesterases produce fatty acids that clearly play roles in plant-insect or plant-microbial interactions, most plant acyl thioesterases have yet to be fully characterized both in terms of their substrate specificities and their functions. The biotechnological applications of plant acyl thioesterases and synthetases are also discussed, as there is significant interest in these enzymes as catalysts for the sustainable production of fatty acids and their derivatives for industrial uses.
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Affiliation(s)
- Rebecca S Kalinger
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Ian P Pulsifer
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Shelley R Hepworth
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
| | - Owen Rowland
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
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Identification and Functional Characterization of a Soybean ( Glycine max) Thioesterase that Acts on Intermediates of Fatty Acid Biosynthesis. PLANTS 2019; 8:plants8100397. [PMID: 31597241 PMCID: PMC6843456 DOI: 10.3390/plants8100397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 09/21/2019] [Accepted: 10/02/2019] [Indexed: 11/16/2022]
Abstract
(1) Background: Plants possess many acyl-acyl carrier protein (acyl-ACP) thioesterases (TEs) with unique specificity. One such TE is methylketone synthase 2 (MKS2), an enzyme with a single-hotdog-fold structure found in several tomato species that hydrolyzes 3-ketoacyl-ACPs to give free 3-ketoacids. (2) Methods: In this study, we identified and characterized a tomato MKS2 homolog gene, namely, GmMKS2, in the genome of soybean (Glycine max). (3) Results: GmMKS2 underwent alternative splicing to produce three alternative transcripts, but only one encodes a protein with thioesterase activity when recombinantly expressed in Escherichia coli. Heterologous expression of the main transcript of GmMKS2, GmMKS2-X2, in E. coli generated various types of fatty acids, including 3-ketoacids-with 3-ketotetradecenoic acid (14:1) being the most abundant-cis-Δ5-dodecanoic acid, and 3-hydroxyacids, suggesting that GmMKS2 acts as an acyl-ACP thioesterase. In plants, the GmMKS2-X2 transcript level was found to be higher in the roots compared to other examined organs. In silico analysis revealed that there is a substantial enrichment of putative cis-regulatory elements related to disease-resistance responses and abiotic stress responses in the promoter of this gene. (4) Conclusions: GmMKS2 showed broad substrate specificities toward a wide range of acyl-ACPs that varied in terms of chain length, oxidation state, and saturation degree. Our results suggest that GmMKS2 might have a stress-related physiological function in G. max.
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Characterization of Solanum melongena Thioesterases Related to Tomato Methylketone Synthase 2. Genes (Basel) 2019; 10:genes10070549. [PMID: 31323901 PMCID: PMC6678348 DOI: 10.3390/genes10070549] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Revised: 07/11/2019] [Accepted: 07/16/2019] [Indexed: 11/16/2022] Open
Abstract
2-Methylketones are involved in plant defense and fragrance and have industrial applications as flavor additives and for biofuel production. We isolated three genes from the crop plant Solanum melongena (eggplant) and investigated these as candidates for methylketone production. The wild tomato methylketone synthase 2 (ShMKS2), which hydrolyzes β-ketoacyl-acyl carrier proteins (ACP) to release β-ketoacids in the penultimate step of methylketone synthesis, was used as a query to identify three homologs from S. melongena: SmMKS2-1, SmMKS2-2, and SmMKS2-3. Expression and functional characterization of SmMKS2s in E. coli showed that SmMKS2-1 and SmMKS2-2 exhibited the thioesterase activity against different β-ketoacyl-ACP substrates to generate the corresponding saturated and unsaturated β-ketoacids, which can undergo decarboxylation to form their respective 2-methylketone products, whereas SmMKS2-3 showed no activity. SmMKS2-1 was expressed at high level in leaves, stems, roots, flowers, and fruits, whereas expression of SmMKS2-2 and SmMKS2-3 was mainly in flowers and fruits, respectively. Expression of SmMKS2-1 was induced in leaves by mechanical wounding, and by methyl jasmonate or methyl salicylate, but SmMKS2-2 and SmMKS2-3 genes were not induced. SmMKS2-1 is a candidate for methylketone-based defense in eggplant, and both SmMKS2-1 and SmMKS2-2 are novel MKS2 enzymes for biosynthesis of methylketones as feedstocks to biofuel production.
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Abstract
Chloroplasts contain high amounts of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) and low levels of the anionic lipids sulfoquinovosyldiacylglycerol (SQDG), phosphatidylglycerol (PG), and glucuronosyldiacylglycerol (GlcADG). The mostly extraplastidial lipid phosphatidylcholine is found only in the outer envelope. Chloroplasts are the major site for fatty acid synthesis. In Arabidopsis, a certain proportion of glycerolipids is entirely synthesized in the chloroplast (prokaryotic lipids). Fatty acids are also exported to the endoplasmic reticulum and incorporated into lipids that are redistributed to the chloroplast (eukaryotic lipids). MGDG, DGDG, SQDG, and PG establish the thylakoid membranes and are integral constituents of the photosynthetic complexes. Phosphate deprivation induces phospholipid degradation accompanied by the increase in DGDG, SQDG, and GlcADG. During freezing and drought stress, envelope membranes are stabilized by the conversion of MGDG into oligogalactolipids. Senescence and chlorotic stress lead to lipid and chlorophyll degradation and the deposition of acyl and phytyl moieties as fatty acid phytyl esters.
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Affiliation(s)
- Georg Hölzl
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, 53115 Bonn, Germany;
| | - Peter Dörmann
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, 53115 Bonn, Germany;
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Kalinger RS, Pulsifer IP, Rowland O. Elucidating the substrate specificities of acyl-lipid thioesterases from diverse plant taxa. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2018; 127:104-118. [PMID: 29571003 DOI: 10.1016/j.plaphy.2018.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/09/2018] [Accepted: 03/12/2018] [Indexed: 05/21/2023]
Abstract
Acyl-ACP thioesterase enzymes, which cleave fatty acyl thioester bonds to release free fatty acids, contribute to much of the fatty acid diversity in plants. In Arabidopsis thaliana, a family of four single hot-dog fold domain, plastid-localized acyl-lipid thioesterases (AtALT1-4) generate medium-chain (C6-C14) fatty and β-keto fatty acids as secondary metabolites. These volatile products may serve to attract insect pollinators or deter predatory insects. Homologs of AtALT1-4 are present in all plant taxa, but are nearly all uncharacterized. Despite high sequence identity, AtALT1-4 generate different lipid products, suggesting that ALT homologs in other plants also have highly varied activities. We investigated the catalytic diversity of ALT-like thioesterases by screening the substrate specificities of 15 ALT homologs from monocots, eudicots, a lycophyte, a green microalga, and the ancient gymnosperm Gingko biloba, via expression in Escherichia coli. Overall, these enzymes had highly varied substrate preferences compared to one another and to AtALT1-4, and could be classified into four catalytic groups comprising members from diverse taxa. Group 1 ALTs primarily generated 14:1 β-keto fatty acids, Group 2 ALTs produced 6-10 carbon fatty/β-keto fatty acids, Group 3 ALTs predominantly produced 12-14 carbon fatty acids, and Group 4 ALTs mainly generated 16 carbon fatty acids. Enzymes in each group differed significantly in the quantities of lipids and types of minor products they generated in E. coli. Medium-chain fatty acids are used to manufacture insecticides, pharmaceuticals, and biofuels, and ALT-like proteins are ideal candidates for metabolic engineering to produce specific fatty acids in significant quantities.
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Affiliation(s)
- Rebecca S Kalinger
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Ian P Pulsifer
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Owen Rowland
- Department of Biology and Institute of Biochemistry, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.
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von Wettstein-Knowles P. The Polyketide Components of Waxes and the Cer-cqu Gene Cluster Encoding a Novel Polyketide Synthase, the β-Diketone Synthase, DKS. PLANTS 2017; 6:plants6030028. [PMID: 28698520 PMCID: PMC5620584 DOI: 10.3390/plants6030028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 06/21/2017] [Accepted: 06/30/2017] [Indexed: 01/13/2023]
Abstract
The primary function of the outermost, lipophilic layer of plant aerial surfaces, called the cuticle, is preventing non-stomatal water loss. Its exterior surface is often decorated with wax crystals, imparting a blue–grey color. Identification of the barley Cer-c, -q and -u genes forming the 101 kb Cer-cqu gene cluster encoding a novel polyketide synthase—the β-diketone synthase (DKS), a lipase/carboxyl transferase, and a P450 hydroxylase, respectively, establishes a new, major pathway for the synthesis of plant waxes. The major product is a β-diketone (14,16-hentriacontane) aliphatic that forms long, thin crystalline tubes. A pathway branch leads to the formation of esterified alkan-2-ols.
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Affiliation(s)
- Penny von Wettstein-Knowles
- Section for Biomolecular Sciences, Department of Biology, University of Copenhagen, Ole Maaloees Vej 5, DK-2200 Copenhagen N, Denmark.
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Kelly AA, Feussner I. Oil is on the agenda: Lipid turnover in higher plants. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:1253-1268. [PMID: 27155216 DOI: 10.1016/j.bbalip.2016.04.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 04/23/2016] [Accepted: 04/25/2016] [Indexed: 12/13/2022]
Abstract
Lipases hydrolyze ester bonds within lipids. This process is called lipolysis. They are key players in lipid turnover and involved in numerous metabolic pathways, many of which are shared between organisms like the mobilization of neutral or storage lipids or lipase-mediated membrane lipid homeostasis. Some reactions though are predominantly present in certain organisms, such as the production of signaling molecules (endocannabinoids) by diacylglycerol (DAG) and monoacylglycerol (MAG) lipases in mammals and plants or the jasmonate production in flowering plants. This review aims at giving an overview of the different functional classes of lipases and respective well-known activities, with a focus on the most recent findings in plant biology for selected classes. Here we will put an emphasis on the physiological role and contribution of lipases to the turnover of neutral lipids found in seed oil and other vegetative tissue as candidates for increasing the economical values of crop plants. This article is part of a Special Issue entitled: Plant Lipid Biology edited by Kent D. Chapman and Ivo Feussner.
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Affiliation(s)
- Amélie A Kelly
- Georg-August-University, Albrecht-von-Haller-Institute for Plant Sciences, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
| | - Ivo Feussner
- Georg-August-University, Albrecht-von-Haller-Institute for Plant Sciences, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany; Georg-August-University, Göttingen Center for Molecular Biosciences (GZMB), Justus-von-Liebig Weg 11, 37077 Göttingen, Germany; Georg-August-University, International Center for Advanced Studies of Energy Conversion (ICASEC), Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
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