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Gutbrod P, Yang W, Grujicic GV, Peisker H, Gutbrod K, Du LF, Dörmann P. Phytol derived from chlorophyll hydrolysis in plants is metabolized via phytenal. J Biol Chem 2021; 296:100530. [PMID: 33713704 PMCID: PMC8054155 DOI: 10.1016/j.jbc.2021.100530] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 03/01/2021] [Accepted: 03/09/2021] [Indexed: 12/30/2022] Open
Abstract
Phytol is the isoprenoid alcohol bound in ester linkage to chlorophyll, the most abundant photosynthetic pigment in plants. During leaf senescence, large amounts of phytol are released by chlorophyll degradation. However, the pathway of phytol catabolism in plants is unknown. We hypothesized that phytol degradation in plants might involve its oxidation into the long-chain aldehyde phytenal. Using GC-MS for aldehyde quantification after derivatization with methylhydroxylamine, phytenal was identified in leaves, whereas other long-chain aldehydes (phytanal and pristanal) were barely detectable. We found that phytenal accumulates during chlorotic stresses, for example, salt stress, dark-induced senescence, and nitrogen deprivation. The increase in the phytenal content is mediated at least in part independently of enzyme activities, and it is independent of light. Characterization of phytenal accumulation in the pao1 mutant affected in chlorophyll degradation revealed that phytenal is an authentic phytol metabolite derived from chlorophyll breakdown. The increase in phytenal was even stronger in mutants affected in the production of other phytol metabolites including vte5-2 (tocopherol deficient) and pes1 pes2 (fatty acid phytyl ester deficient). Therefore, phytenal accumulation is controlled by competing, alternative pathways of phosphorylation (leading to tocopherol production) or esterification (fatty acid phytyl ester production). As a consequence, the content of phytenal is maintained at low levels, presumably to minimize its toxic effects caused by its highly reactive aldehyde group that can form covalent bonds with and inactivate the amino groups of proteins.
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Affiliation(s)
- Philipp Gutbrod
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Bonn, Germany
| | - Wentao Yang
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Bonn, Germany; Key Laboratory of Bio-Resources and Eco-Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China
| | - Goran Vuk Grujicic
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Bonn, Germany
| | - Helga Peisker
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Bonn, Germany
| | - Katharina Gutbrod
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Bonn, Germany
| | - Lin Fang Du
- Key Laboratory of Bio-Resources and Eco-Environment of the Ministry of Education, College of Life Sciences, Sichuan University, Chengdu, China.
| | - Peter Dörmann
- Institute of Molecular Physiology and Biotechnology of Plants (IMBIO), University of Bonn, Bonn, Germany.
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Phytol in a pharma-medico-stance. Chem Biol Interact 2015; 240:60-73. [DOI: 10.1016/j.cbi.2015.07.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Revised: 07/01/2015] [Accepted: 07/24/2015] [Indexed: 01/02/2023]
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Lagoutte R, Šebesta P, Jiroš P, Kalinová B, Jirošová A, Straka J, Černá K, Šobotník J, Cvačka J, Jahn U. Total synthesis, proof of absolute configuration, and biosynthetic origin of stylopsal, the first isolated sex pheromone of strepsiptera. Chemistry 2013; 19:8515-24. [PMID: 23630024 DOI: 10.1002/chem.201204196] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 03/15/2013] [Indexed: 11/10/2022]
Abstract
The asymmetric total synthesis of the diastereomers of stylopsal establishes the absolute configuration of the first reported sex pheromone of the twisted-wing parasite Stylops muelleri as (3R,5R,9R)-trimethyldodecanal. The key steps for the diastereo- and enantiodivergent introduction of the methyl groups are two different types of asymmetric conjugate addition reactions of organocopper reagents to α,β-unsaturated esters, whereas the dodecanal skeleton is assembled by Wittig reactions. The structure of the natural product was confirmed by chiral gas chromatography (GC) techniques, GC/MS and GC/electroantennography (EAD) as well as field tests. An investigation into the biosynthesis of the pheromone revealed that it is likely to be produced by decarboxylation of a 4,6,10-trimethyltridecanoic acid derivative, which was found in substantial amounts in the fat body of the female, but not in the host bee Andrena vaga. This triple-branched fatty acid precursor thus seems to be biosynthesized de novo through a polyketide pathway with two consecutive propionate-propionate-acetate assemblies to form the complete skeleton. The simplified, motionless and fully host-dependent female exploits a remarkable strategy to maximize its reproductive success by employing a relatively complex and potent sex pheromone.
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Affiliation(s)
- Roman Lagoutte
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
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The role of 2-hydroxyacyl-CoA lyase, a thiamin pyrophosphate-dependent enzyme, in the peroxisomal metabolism of 3-methyl-branched fatty acids and 2-hydroxy straight-chain fatty acids. Biochem Soc Trans 2008; 35:876-80. [PMID: 17956236 DOI: 10.1042/bst0350876] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
2-Hydroxyphytanoyl-CoA lyase (abbreviated as 2-HPCL), renamed to 2-hydroxyacyl-CoA lyase (abbreviated as HACL1), is the first peroxisomal enzyme in mammals that has been found to be dependent on TPP (thiamin pyrophosphate). It was discovered in 1999, when studying alpha-oxidation of phytanic acid. HACL1 has an important role in at least two pathways: (i) the degradation of 3-methyl-branched fatty acids like phytanic acid and (ii) the shortening of 2-hydroxy long-chain fatty acids. In both cases, HACL1 catalyses the cleavage step, which involves the splitting of a carbon-carbon bond between the first and second carbon atom in a 2-hydroxyacyl-CoA intermediate leading to the production of an (n-1) aldehyde and formyl-CoA. The latter is rapidly converted into formate and subsequently to CO(2). HACL1 is a homotetramer and has a PTS (peroxisomal targeting signal) at the C-terminal side (PTS1). No deficiency of HACL1 has been described yet in human, but thiamin deficiency might affect its activity.
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Jansen GA, Wanders RJA. Alpha-Oxidation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1763:1403-12. [PMID: 16934890 DOI: 10.1016/j.bbamcr.2006.07.012] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Accepted: 07/24/2006] [Indexed: 11/15/2022]
Abstract
Phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) is a branched chain fatty acid, which is a constituent of the human diet. The presence of the 3-methyl group of phytanic acid prevents degradation by beta-oxidation. Instead, the terminal carboxyl group is first removed by alpha-oxidation. The mechanism of the alpha-oxidation pathway and the enzymes involved are described in this review.
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Affiliation(s)
- Gerbert A Jansen
- Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academic Medical Centre, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.
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Jansen GA, Waterham HR, Wanders RJA. Molecular basis of Refsum disease: sequence variations in phytanoyl-CoA hydroxylase (PHYH) and the PTS2 receptor (PEX7). Hum Mutat 2004; 23:209-18. [PMID: 14974078 DOI: 10.1002/humu.10315] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Refsum disease has long been known to be an inherited disorder of lipid metabolism characterized by the accumulation of phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) caused by an alpha-oxidation deficiency of this branched chain fatty acid in peroxisomes. The mechanism of phytanic acid alpha-oxidation and the enzymes involved had long remained mysterious, but they have been resolved in recent years. This has led to the resolution of the molecular basis of Refsum disease. Interestingly, Refsum disease is genetically heterogeneous; two genes, PHYH (also named PAHX) and PEX7, have been identified to cause Refsum disease, as reviewed in this work.
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Affiliation(s)
- Gerbert A Jansen
- Laboratory of Genetic Metabolic Diseases, Department of Clinical Chemistry, Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands
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Foulon V, Asselberghs S, Geens W, Mannaerts GP, Casteels M, Van Veldhoven PP. Further studies on the substrate spectrum of phytanoyl-CoA hydroxylase: implications for Refsum disease? J Lipid Res 2003; 44:2349-55. [PMID: 12923223 DOI: 10.1194/jlr.m300230-jlr200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Refsum disease is a peroxisomal disorder characterized by adult-onset retinitis pigmentosa, anosmia, sensory neuropathy, ataxia, and an accumulation of phytanic acid in plasma and tissues. Approximately 45% of cases are caused by mutations in phytanoyl-CoA hydroxylase (PAHX), the enzyme catalyzing the second step in the peroxisomal alpha-oxidation of 3-methyl-branched fatty acids. To study the substrate specificity of human PAHX, different 3-alkyl-branched substrates were synthesized and incubated with a recombinant polyhistidine-tagged protein. The enzyme showed activity not only toward racemic phytanoyl-CoA and the isomers of 3-methylhexadecanoyl-CoA, but also toward a variety of other mono-branched 3-methylacyl-CoA esters with a chain length down to seven carbon atoms. Furthermore, PAHX hydroxylated a 3-ethylacyl-CoA quite well, whereas a 3-propylacyl-CoA was a poor substrate. Hydroxylation of neither 2- or 4-methyl-branched acyl-CoA esters, nor long or very long straight-chain acyl-CoA esters could be detected. The results presented in this paper show that the substrate specificity of PAHX, with regard to the length of both the acyl-chain and the branch at position 3, is broader than expected. Hence, Refsum disease might be characterized by an accumulation of not only phytanic acid but also other 3-alkyl-branched fatty acids.
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Affiliation(s)
- Veerle Foulon
- Departement Moleculaire Celbiologie, Afdeling Farmacologie, Katholieke Universiteit Leuven, Campus Gasthuisberg, Herestraat 49, B-3000 Leuven, Belgium
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Mukherji M, Schofield CJ, Wierzbicki AS, Jansen GA, Wanders RJA, Lloyd MD. The chemical biology of branched-chain lipid metabolism. Prog Lipid Res 2003; 42:359-76. [PMID: 12814641 DOI: 10.1016/s0163-7827(03)00016-x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mammalian metabolism of some lipids including 3-methyl and 2-methyl branched-chain fatty acids occurs within peroxisomes. Such lipids, including phytanic and pristanic acids, are commonly found within the human diet and may be derived from chlorophyll in plant extracts. Due to the presence of a methyl group at its beta-carbon, the well-characterised beta-oxidation pathway cannot degrade phytanic acid. Instead its alpha-methylene group is oxidatively excised to give pristanic acid, which can be metabolised by the beta-oxidation pathway. Many defects in the alpha-oxidation pathway result in an accumulation of phytanic acid, leading to neurological distress, deterioration of vision, deafness, loss of coordination and eventual death. Details of the alpha-oxidation pathway have only recently been elucidated, and considerable progress has been made in understanding the detailed enzymology of one of the oxidative steps within this pathway. This review summarises these recent advances and considers the roles and likely mechanisms of the enzymes within the alpha-oxidation pathway.
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Affiliation(s)
- Mridul Mukherji
- The Oxford Centre for Molecular Sciences & The Dyson Perrins Laboratory, South Parks Road, Oxford OX1 3QY, UK
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Casteels M, Foulon V, Mannaerts GP, Van Veldhoven PP. Alpha-oxidation of 3-methyl-substituted fatty acids and its thiamine dependence. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:1619-27. [PMID: 12694175 DOI: 10.1046/j.1432-1033.2003.03534.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
3-Methyl-branched fatty acids, as phytanic acid, undergo peroxisomal alpha-oxidation in which they are shortened by 1 carbon atom. This process includes four steps: activation, 2-hydroxylation, thiamine pyrophosphate dependent cleavage and aldehyde dehydrogenation. The thiamine pyrophosphate dependence of the third step is unique in peroxisomal mammalian enzymology. Human pathology due to a deficient alpha-oxidation is mostly linked to mutations in the gene coding for the second enzyme of the sequence, phytanoyl-CoA hydroxylase.
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Affiliation(s)
- Minne Casteels
- Afdeling Farmacologie, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Belgium.
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Wanders RJA, Jansen GA, Lloyd MD. Phytanic acid alpha-oxidation, new insights into an old problem: a review. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1631:119-35. [PMID: 12633678 DOI: 10.1016/s1388-1981(03)00003-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Phytanic acid (3,7,10,14-tetramethylhexadecanoic acid) is a branched-chain fatty acid which is known to accumulate in a number of different genetic diseases including Refsum disease. Due to the presence of a methyl-group at the 3-position, phytanic acid and other 3-methyl fatty acids can not undergo beta-oxidation but are first subjected to fatty acid alpha-oxidation in which the terminal carboxyl-group is released as CO(2). The mechanism of alpha-oxidation has long remained obscure but has been resolved in recent years. Furthermore, peroxisomes have been found to play an indispensable role in fatty acid alpha-oxidation, and the complete alpha-oxidation machinery is probably localized in peroxisomes. This Review describes the current state of knowledge about fatty acid alpha-oxidation in mammals with particular emphasis on the mechanism involved and the enzymology of the pathway.
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Affiliation(s)
- Ronald J A Wanders
- Laboratory Genetic Metabolic Diseases, Department of Pediatrics/Emma Children's Hospital and Clinical Chemistry, Academic Medical Centre, University Hospital Amsterdam, Room F0-224, P.O. Box 22700, 1100 DE Amsterdam, The Netherlands.
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Mukherji M, Kershaw NJ, Schofield CJ, Wierzbicki AS, Lloyd MD. Utilization of sterol carrier protein-2 by phytanoyl-CoA 2-hydroxylase in the peroxisomal alpha oxidation of phytanic acid. CHEMISTRY & BIOLOGY 2002; 9:597-605. [PMID: 12031666 DOI: 10.1016/s1074-5521(02)00139-4] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Since it possesses a 3-methyl group, phytanic acid is degraded by a peroxisomal alpha-oxidation pathway, the first step of which is catalyzed by phytanoyl-CoA 2-hydroxylase (PAHX). Mutations in human PAHX cause phytanic acid accumulations leading to Adult Refsum's Disease (ARD), which is also observed in a sterol carrier protein 2 (SCP-2)-deficient mouse model. Phytanoyl-CoA is efficiently 2-hydroxylated by PAHX in vitro in the presence of mature SCP-2. Other straight-chain fatty acyl-CoA esters were also 2-hydroxylated and the products isolated and characterized. Use of SCP-2 increases discrimination between straight-chain (e.g., hexadecanoyl-CoA) and branched-chain (e.g., phytanoyl-CoA) substrates by PAHX. The results explain the phytanic acid accumulation in the SCP-2-deficient mouse model and suggest that some of the common symptoms of ARD and other peroxisomal diseases may arise in part due to defects in SCP-2 function caused by increased phytanic acid levels.
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Affiliation(s)
- Mridul Mukherji
- The Oxford Centre for Molecular Science, The Dyson Perrins Laboratory, South Parks Road, OX1 3QY, Oxford, United Kingdom
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12
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Abstract
Phytanic acid is a methyl-branched fatty acid present in the human diet. Due to its structure, degradation by beta-oxidation is impossible. Instead, phytanic acid is oxidized by alpha-oxidation, yielding pristanic acid. Despite many efforts to elucidate the alpha-oxidation pathway, it remained unknown for more than 30 years. In recent years, the mechanism of alpha-oxidation as well as the enzymes involved in the process have been elucidated. The process was found to involve activation, followed by hydroxylase, lyase and dehydrogenase reactions. Part, if not all of the reactions were found to take place in peroxisomes. The final product of phytanic acid alpha-oxidation is pristanic acid. This fatty acid is degraded by peroxisomal beta-oxidation. After 3 steps of beta-oxidation in the peroxisome, the product is esterified to carnitine and shuttled to the mitochondrion for further oxidation. Several inborn errors with one or more deficiencies in the phytanic acid and pristanic degradation have been described. The clinical expressions of these disorders are heterogeneous, and vary between severe neonatal and often fatal symptoms and milder syndromes with late onset. Biochemically, these disorders are characterized by accumulation of phytanic and/or pristanic acid in tissues and body fluids. Several of the inborn errors involving phytanic acid and/or pristanic acid metabolism have been characterized on the molecular level.
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Affiliation(s)
- N M Verhoeven
- Department of Clinical Chemistry, Metabolic Unit, VU Medical Center, PO Box 7057, 1007 MB, Amsterdam, The Netherlands.
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Wanders RJ, Jansen GA, Skjeldal OH. Refsum disease, peroxisomes and phytanic acid oxidation: a review. J Neuropathol Exp Neurol 2001; 60:1021-31. [PMID: 11706932 DOI: 10.1093/jnen/60.11.1021] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Refsum disease was first recognized as a distinct disease entity by Sigvald Refsum in the 1940s. The discovery of markedly elevated levels of the branched-chain fatty acid phytanic acid in certain patients marked Refsum disease as a disorder of lipid metabolism. Although it was immediately recognized that the accumulation of phytanic acid is due to its deficient breakdown in Refsum disease patients, the true enzymatic defect remained mysterious until recently. A major breakthrough in this respect was the resolution of the mechanism of phytanic acid alpha-oxidation in humans. In this review we describe the many aspects of Refsum disease from the clinical signs and symptoms to the enzyme and molecular defect plus the recent identification of genetic heterogeneity in Refsum disease.
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Affiliation(s)
- R J Wanders
- Academic Medical Centre, University of Amsterdam, Department of Pediatrics, The Netherlands
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Kershaw NJ, Mukherji M, MacKinnon CH, Claridge TD, Odell B, Wierzbicki AS, Lloyd MD, Schofield CJ. Studies on phytanoyl-CoA 2-hydroxylase and synthesis of phytanoyl-coenzyme A. Bioorg Med Chem Lett 2001; 11:2545-8. [PMID: 11549466 DOI: 10.1016/s0960-894x(01)00494-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Phytanoyl-CoA 2-hydroxylase (PAHX), an iron(II) and 2-oxoglutarate-dependent oxygenase, catalyses an essential step in the mammalian metabolism of beta-methylated fatty acids. Phytanoyl-CoA was synthesised and used to develop in vitro assays for PAHX. The product of the reaction was confirmed as 2-hydroxyphytanoyl-CoA by NMR and mass spectrometric analyses. In accord with in vivo analyses, hydroxylation of both 3R and 3S epimers of the substrate was catalysed by PAHX. Both pro- and mature- forms of PAHX were fully active.
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Affiliation(s)
- N J Kershaw
- The Oxford Centre for Molecular Sciences and The Dyson Perrins Laboratory, South Parks Road, OX1 3QY, Oxford, UK
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Jansen GA, van den Brink DM, Ofman R, Draghici O, Dacremont G, Wanders RJ. Identification of pristanal dehydrogenase activity in peroxisomes: conclusive evidence that the complete phytanic acid alpha-oxidation pathway is localized in peroxisomes. Biochem Biophys Res Commun 2001; 283:674-9. [PMID: 11341778 DOI: 10.1006/bbrc.2001.4835] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phytanic acid (3,7,11,15-tetramethylhexadecanoic acid) is a branched-chain fatty acid which, due to the methyl-group at the 3-position, can not undergo beta-oxidation unless the terminal carboxyl-group is removed by alpha-oxidation. The structure of the phytanic acid alpha-oxidation machinery in terms of the reactions involved, has been resolved in recent years and includes a series of four reactions: (1) activation of phytanic acid to phytanoyl-CoA, (2) hydroxylation of phytanoyl-CoA to 2-hydroxyphytanoyl-CoA, (3) cleavage of 2-hydroxyphytanoyl-CoA to pristanal and formyl-CoA, and (4) oxidation of pristanal to pristanic acid. The subcellular localization of the enzymes involved has remained enigmatic, with the exception of phytanoyl-CoA hydroxylase and 2-hydroxyphytanoyl-CoA lyase which are both localized in peroxisomes. The oxidation of pristanal to pristanic acid has been claimed to be catalysed by the microsomal aldehyde dehydrogenase FALDH encoded by the ALDH10-gene. Making use of mutant fibroblasts deficient in FALDH activity, we show that phytanic acid alpha-oxidation is completely normal in these cells. Furthermore, we show that pristanal dehydrogenase activity is not fully deficient in FALDH-deficient cells, implying the existence of one or more additional aldehyde dehydrogenases reacting with pristanal. Using subcellular localization studies, we now show that peroxisomes contain pristanal dehydrogenase activity which leads us to conclude that the complete phytanic acid alpha-oxidation pathway is localized in peroxisomes.
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Affiliation(s)
- G A Jansen
- Department of Clinical Chemistry, Department of Pediatrics, University of Amsterdam, Academic Medical Centre, Emma Children's Hospital, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands
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Jansen GA, Denis S, Verhoeven NM, Jakobs C, Wanders RJ. Phytanic acid alpha-oxidation in man: identification of 2-hydroxyphytanoyl-CoA lyase, a peroxisomal enzyme with normal activity in Zellweger syndrome. J Inherit Metab Dis 2000; 23:421-4. [PMID: 10896309 DOI: 10.1023/a:1005672406773] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- G A Jansen
- University of Amsterdam, Academic Medical Centre, Department of Clinical Chemistry, Emma Children's Hospital, The Netherlands
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Jones JM, Morrell JC, Gould SJ. Identification and characterization of HAOX1, HAOX2, and HAOX3, three human peroxisomal 2-hydroxy acid oxidases. J Biol Chem 2000; 275:12590-7. [PMID: 10777549 DOI: 10.1074/jbc.275.17.12590] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Computer-based approaches identified three distinct human 2-hydroxy acid oxidase genes, HAOX1, HAOX2, and HAOX3, that encode proteins with significant sequence similarity to plant glycolate oxidase, a prototypical 2-hydroxy acid oxidase. The products of these genes are targeted to peroxisomes and have 2-hydroxy acid oxidase activities. Each gene displays a distinct tissue-specific pattern of expression, and each enzyme exhibits distinct substrate preferences. HAOX1 is expressed primarily in liver and pancreas and is most active on the two-carbon substrate, glycolate, but is also active on 2-hydroxy fatty acids. HAOX2 is expressed predominantly in liver and kidney and displays highest activity toward 2-hydroxypalmitate. HAOX3 expression was detected only in pancreas, and this enzyme displayed a preference for the medium chain substrate 2-hydroxyoctanoate. These results indicate that all three human 2-hydroxy acid oxidases are involved in the oxidation of 2-hydroxy fatty acids and may also contribute to the general pathway of fatty acid alpha-oxidation. Primary hyperoxaluria type 1 (PH1) is caused by defects in peroxisomal alanine-glyoxylate aminotransferase, the enzyme that normally eliminates intraperoxisomal glyoxylate. The presence of HAOX1 in liver and kidney peroxisomes and the ability of HAOX1 to oxidize glyoxylate to oxalate implicate HAOX1 as a mediator of PH1 pathophysiology.
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Affiliation(s)
- J M Jones
- Department of Biological Chemistry, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
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Van Veldhoven PP, Mannaerts GP, Casteels M, Croes K. Hepatic alpha-oxidation of phytanic acid. A revised pathway. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2000; 466:273-81. [PMID: 10709654 DOI: 10.1007/0-306-46818-2_32] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Synthetic 3-methyl-branched chain fatty acids were used to decipher the breakdown of phytanic acid. Based on results obtained in intact or permeabilized rat hepatocytes, rat liver homogenates or subcellular fractions, a revised alpha-oxidation pathway is proposed which appears to be functioning in man as well. In a first step, the 3-methyl-branched chain fatty acid is activated by an acyl-CoA synthetase. This reaction requires CoA, ATP and Mg2+. Subsequently, the acyl-CoA ester is hydroxylated at position 2 by a peroxisomal dioxygenase. This step is dependent on alpha-oxoglutarate, ascorbate (or glutathione), Fe2+ and O2. The 2-hydroxy-3-methylacyl-CoA intermediate is cleaved by a peroxisomal lyase to formyl-CoA and a 2-methyl-branched fatty aldehyde. Formyl-CoA is (partly enzymically) hydrolyzed to formate, which is then converted, most likely in the cytosol, to CO2. In the presence of NAD+, the aldehyde is dehydrogenated to a 2-methyl-branched fatty acid, presumably by a peroxisomal aldehyde dehydrogenase. This acid can--after activation--be degraded via a D-specific peroxisomal beta-oxidation system.
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Affiliation(s)
- P P Van Veldhoven
- Katholieke Universiteit Leuven, Afdeling Farmakologie Herestraat, Belgium.
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Wanders RJ. Functions and dysfunctions of peroxisomes in fatty acid alpha- and beta-oxidation. New insights. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2000; 466:283-99. [PMID: 10709655 DOI: 10.1007/0-306-46818-2_33] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Affiliation(s)
- R J Wanders
- University of Amsterdam, Depts. Pediatrics, Emma Children's Hospital and Clinical Chemistry, The Netherlands
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Hiltunen JK, Qin Y. beta-oxidation - strategies for the metabolism of a wide variety of acyl-CoA esters. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1484:117-28. [PMID: 10760462 DOI: 10.1016/s1388-1981(00)00013-5] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Living organisms are exposed to a number of different fatty acids and their various derivatives arising either via endogenous synthesis or from exogenous sources. These hydrophobic compounds can play specific metabolic, structural or endocrinic functions in the organisms before their elimination, which can be metabolism to CO(2) or to more polar lipid metabolites allowing their excretion. Quantitatively, one of the major pathways metabolizing fatty acids is beta-oxidation, which consists of a set of four reactions operating at the carbons 2 or 3 of acyl-CoA esters and shortening of the acyl-chain. To allow the beta-oxidation of acyl groups with various steric variants to proceed, different strategies have been developed. These strategies include evolution of beta-oxidation enzymes as paralogues showing specificity with respect to either chain-length or modified acyl-chain, metabolic compartmentalization in eukaryotic cells, controlling of substrate transport across membranes, development of auxiliary enzyme systems, acquisition of enzymes with adaptive active sites and recruiting and optimizing enzymes from non-homologous sources allowing them to catalyze a parallel set of reactions with different substrate specificities.
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Affiliation(s)
- J K Hiltunen
- Biocenter Oulu and Department of Biochemistry, University of Oulu, P. O. FIN-90014, Oulun yliopisto, Finland.
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21
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Phytanoyl-CoA hydroxylase: recognition of 3-methyl-branched acyl-CoAs and requirement for GTP or ATP and Mg2+ in addition to its known hydroxylation cofactors. J Lipid Res 2000. [DOI: 10.1016/s0022-2275(20)32411-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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22
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Jansen GA, Ofman R, Denis S, Ferdinandusse S, Hogenhout EM, Jakobs C, Wanders RJ. Phytanoyl-CoA hydroxylase from rat liver: protein purification and cDNA cloning with implications for the subcellular localization of phytanic acid α-oxidation. J Lipid Res 1999. [DOI: 10.1016/s0022-2275(20)32099-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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23
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Jansen GA, Verhoeven NM, Denis S, Romeijn G, Jakobs C, ten Brink HJ, Wanders RJ. Phytanic acid alpha-oxidation: identification of 2-hydroxyphytanoyl-CoA lyase in rat liver and its localisation in peroxisomes. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1440:176-82. [PMID: 10521701 DOI: 10.1016/s1388-1981(99)00126-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Phytanic acid is broken down by alpha-oxidation in three steps finally yielding pristanic acid. The first step occurs in peroxisomes and is catalysed by phytanoyl-CoA hydroxylase. We have studied the second step in the alpha-oxidation pathway, which involves conversion of 2-hydroxyphytanoyl-CoA to pristanal catalysed by 2-hydroxyphytanoyl-CoA lyase. To this end, we have developed a stable isotope dilution gas chromatography-mass spectrometry assay allowing activity measurements in rat liver homogenates. Cell fractionation studies demonstrate that in rat liver 2-hydroxyphytanoyl-CoA lyase is localised in peroxisomes. This finding may have important implications for inherited diseases in man characterised by impaired phytanic acid alpha-oxidation.
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Affiliation(s)
- G A Jansen
- University of Amsterdam, Academic Medical Centre, Department of Pediatrics, Emma Children's Hospital, Laboratory for Genetic Metabolic Diseases (Room F0-224), P.O. Box 22700, 1100 DE, Amsterdam, Netherlands
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24
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Foulon V, Antonenkov VD, Croes K, Waelkens E, Mannaerts GP, Van Veldhoven PP, Casteels M. Purification, molecular cloning, and expression of 2-hydroxyphytanoyl-CoA lyase, a peroxisomal thiamine pyrophosphate-dependent enzyme that catalyzes the carbon-carbon bond cleavage during alpha-oxidation of 3-methyl-branched fatty acids. Proc Natl Acad Sci U S A 1999; 96:10039-44. [PMID: 10468558 PMCID: PMC17838 DOI: 10.1073/pnas.96.18.10039] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In the third step of the alpha-oxidation of 3-methyl-branched fatty acids such as phytanic acid, a 2-hydroxy-3-methylacyl-CoA is cleaved into formyl-CoA and a 2-methyl-branched fatty aldehyde. The cleavage enzyme was purified from the matrix protein fraction of rat liver peroxisomes and identified as a protein made up of four identical subunits of 63 kDa. Its activity proved to depend on Mg(2+) and thiamine pyrophosphate, a hitherto unrecognized cofactor of alpha-oxidation. Formyl-CoA and 2-methylpentadecanal were identified as reaction products when the purified enzyme was incubated with 2-hydroxy-3-methylhexadecanoyl-CoA as the substrate. Hence the enzyme catalyzes a carbon-carbon cleavage, and we propose calling it 2-hydroxyphytanoyl-CoA lyase. Sequences derived from tryptic peptides of the purified rat protein were used as queries to recover human expressed sequence tags from the databases. The composite cDNA sequence of the human lyase contained an ORF of 1,734 bases that encodes a polypeptide with a calculated molecular mass of 63,732 Da. Recombinant human protein, expressed in mammalian cells, exhibited lyase activity. The lyase displayed homology to a putative Caenorhabditis elegans protein that resembles bacterial oxalyl-CoA decarboxylases. Similarly to the decarboxylases, a thiamine pyrophosphate-binding consensus domain was present in the C-terminal part of the lyase. Although no peroxisome targeting signal, neither 1 nor 2, was apparent, transfection experiments with constructs encoding green fluorescent protein fused to the full-length lyase or its C-terminal pentapeptide indicated that the C terminus of the lyase represents a peroxisome targeting signal 1 variant.
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Affiliation(s)
- V Foulon
- Division of Pharmacology, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Campus Gasthuisberg B-3000 Leuven, Belgium
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25
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Borge GI, Vogt G, Nilsson A. Intermediates and products formed during fatty acid alpha-oxidation in cucumber (Cucumis sativus). Lipids 1999; 34:661-73. [PMID: 10478923 DOI: 10.1007/s11745-999-0411-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Fatty acid alpha-oxidation is an essential metabolic pathway both in plants and in mammals which is still not completely understood. We previously described and purified an alpha-oxidation enzyme in cucumber which has been used in the present investigation of the alpha-oxidation reaction mechanism. Free fatty acids, and not the CoA thioesters, were found to undergo alpha-oxidation in cucumber. 2-Hydroxy- and 2-oxopalmitic acids were identified as palmitic acid alpha-oxidation intermediates by high-performance liquid chromatography and gas chromatography-mass spectrometry analysis in cucumber subcellular 150,000 x g(max) pellets obtained by differential centrifugation. Incubation of purified alpha-oxidation enzyme with [1-14C]palmitic acid resulted in the formation of both the above-described intermediates and the Cn-1 product, pentadecanal, and 14CO2. Besides 14CO2, 14C-formate was identified as an alpha-oxidation product from [1-14C]palmitic acid in cucumber subcellular fractions. Fe2+ stimulated the 14CO2 and 14C-formate production, and the addition of ascorbate and 2-oxoglutarate together with Fe2+ resulted in optimal alpha-oxidation activities, suggesting a dioxygenase reaction mechanism, as previously shown in mammals. NADPH and, to a lesser extent, NADH stimulated the total 14C-formate plus 14CO2 production but had only slight or no effects on 14CO2 production. H2O2 showed concentration-dependent inhibitory effects, while FAD had neither effect on 14CO2 nor 14CO2 plus 14C-formate production. The results in the present study demonstrate that an alpha-oxidation enzyme in cucumber is capable of oxidizing palmitic acid via 2-hydroxy- and 2-oxo-palmitic acid to produce pentadecanal and CO2. In contrast to the subcellular 150,000 x g(max) fraction, the purified alpha-oxidation enzyme could neither produce formate nor convert 14C-formate into 14C02, indicating two possible alpha-oxidation routes in cucumber.
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Affiliation(s)
- G I Borge
- MATFORSK, Norwegian Food Research Institute, As.
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27
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Abstract
Peroxisomes are subcellular organelles catalyzing a number of indispensable functions in cellular metabolism. The importance of peroxisomes in man is stressed by the existence of an expanding group of genetic diseases in which there is an impairment in one or more peroxisomal functions. Much has been learned in recent years about these functions and many of the enzymes involved have been characterized, purified and their cDNAs cloned. This has allowed resolution of the enzymatic and molecular basis of many of the single peroxisomal enzyme deficiencies. Similarly, the molecular basis of the peroxisome biogenesis disorders is also being resolved rapidly thanks to the successful use of CHO as well as yeast mutants. In this paper we will provide an overview of the peroxisomal disorders with particular emphasis on their clinical, biochemical and molecular characteristics.
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Affiliation(s)
- R J Wanders
- University of Amsterdam, Academic Medical Centre, Dept. Pediatrics, Emma Children's Hospital and Clinical Biochemistry, The Netherlands.
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28
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Wierzbicki AS, Sankaralingam A, Lumb PJ, Hardman TC, Sidey MC, Gibberd FB. Transport of phytanic acid on lipoproteins in Refsum disease. J Inherit Metab Dis 1999; 22:29-36. [PMID: 10070615 DOI: 10.1023/a:1005486913371] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Patients with Refsum disease accumulate significant quantities of phytanic acid in adipose and neural tissue. The accumulation can be reversed by following a diet low in phytanic acid, yet the mechanism of transport of this fatty acid is obscure. We investigated the distribution of phytanic acid in different lipoprotein subfractions in 11 patients with Refsum disease and 9 unaffected siblings. Plasma phytanic acid was distributed on VLDL (16.2% +/- 12.2%), IDL (1.77% +/- 1.64%), LDL (34.8% +/- 12.6%) and HDL (14.3% +/- 7.87%). No correlations with any parameter were seen with total phytanic acid content. Weak nonsignificant correlations were found with the fractional distribution of phytanic acid and VLDL triglyceride (r = 0.35; p = 0.12) and plasma HDL-cholesterol (r = 0.32; p = 0.16) and with LDL:HDL cholesterol ratio (r = 0.33; p = 0.14). Significant correlation of the fractional distribution of phytanic acid on lipoprotein particles was noted with the ratio of apolipoprotein B: apolipoprotein A1-containing particles (r = 0.46; p = 0.03) and apolipoprotein B: apolipoprotein A1 in HDL2 (r = 0.53; p = 0.01). This suggests that the import-export balance for phytanic acid in plasma is related to forward and reverse cholesterol transport on lipoprotein particles, and only weakly to plasma cholesterol and triglycerides. These ratios of apolipoprotein particles may play a significant role in determining the rate of phytanic acid elimination in patients with Refsum disease.
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Affiliation(s)
- A S Wierzbicki
- Department of Chemical Pathology, St Thomas' Hospital, London, UK.
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29
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Wanders RJ, Denis S, Ruiter JP, IJlst L, Dacremont G. 2,6-Dimethylheptanoyl-CoA is a specific substrate for long-chain acyl-CoA dehydrogenase (LCAD): evidence for a major role of LCAD in branched-chain fatty acid oxidation. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1393:35-40. [PMID: 9714723 DOI: 10.1016/s0005-2760(98)00053-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Oxidation of straight-chain fatty acids in mitochondria involves the complicated interaction between a large variety of different enzymes. So far four different mitochondrial straight-chain acyl-CoA dehydrogenases have been identified. The physiological function of three of the four acyl-CoA dehydrogenases has been resolved in recent years especially from studies on patients suffering from certain inborn errors of mitochondrial fatty acid beta-oxidation. The physiological role of long-chain acyl-CoA dehydrogenase (LCAD) has remained obscure, however. The results described in this paper provide strong evidence suggesting that LCAD plays a central role in branched-chain fatty acid metabolism since it turns out to be the major acyl-CoA dehydrogenase reacting with 2,6-dimethylheptanoyl-CoA, a metabolite of pristanic acid, which itself is the alpha-oxidation product of phytanic acid.
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Affiliation(s)
- R J Wanders
- Department of Clinical Chemistry, Emma Children's Hospital, Academic Medical Centre, University of Amsterdam, P.O. Box 22700, 1100 DE Amsterdam, The Netherlands.
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30
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Verhoeven NM, Jakobs C, Carney G, Somers MP, Wanders RJ, Rizzo WB. Involvement of microsomal fatty aldehyde dehydrogenase in the alpha-oxidation of phytanic acid. FEBS Lett 1998; 429:225-8. [PMID: 9662422 DOI: 10.1016/s0014-5793(98)00574-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We investigated the role of microsomal fatty aldehyde dehydrogenase (FALDH) in the conversion of pristanal into pristanic acid. Cultured skin fibroblasts from controls and patients with Sjögren-Larsson syndrome (SLS) who are genetically deficient in FALDH activity were incubated with [2,3-(3)H]phytanic acid. The release of aqueous-soluble radioactivity by the SLS cells was decreased to 25% of normal, consistent with an intact formation of pristanal but a deficiency of further oxidation. SLS cells also accumulated four-fold more radioactivity in N-alkyl-phosphatidyl ethanolamine, which arises from incorporation of free aldehyde into phosphatidyl ethanolamine. Recombinant human FALDH expressed in Chinese hamster ovary cells readily oxidized pristanal and cultured fibroblasts from SLS patients showed a severe deficiency in FALDH activity (13% of normal) when pristanal was used as substrate. Nevertheless, SLS patients did not accumulate phytanic acid in their plasma. We conclude that FALDH is involved in the oxidation of pristanal to pristanic acid and that this reaction is deficient in patients with SLS.
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Affiliation(s)
- N M Verhoeven
- Department of Clinical Chemistry, Free University Hospital Amsterdam, The Netherlands
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31
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Chahal A, Khan M, Pai SG, Barbosa E, Singh I. Restoration of phytanic acid oxidation in Refsum disease fibroblasts from patients with mutations in the phytanoyl-CoA hydroxylase gene. FEBS Lett 1998; 429:119-22. [PMID: 9657395 DOI: 10.1016/s0014-5793(98)00575-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Refsum disease (RD) is biochemically characterized by the excessive accumulation of phytanic acid in tissues and body fluids due to deficiency of phytanoyl-CoA hydroxylase (PAHX). In this study, we screened three RD patients and identified a novel deletion (88 amino acids), and a missense mutation (Arg275Trp) in the previously reported PAHX cDNA (Jansen et al., 1997; Mihalik et al., 1997). Moreover, transfection of skin fibroblasts from two RD patients with wild-type PAHX gene restored the activity for alpha-oxidation of phytanic acid. Southern analysis on a somatic cell hybrid panel detected the PAHX gene on chromosome 10, corroborating radiation hybrid and homozygosity mapping data (Mihalik et al., 1997; Nadal et al., 1995).
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Affiliation(s)
- A Chahal
- Department of Pediatrics, Medical University of South Carolina, Charleston 29425, USA
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32
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Abstract
Peroxisomes were long believed to play only a minor role in cellular metabolism but it is now clear that they catalyze a number of important functions. The importance of peroxisomes in humans is stressed by the existence of a group of genetic diseases in man in which one or more peroxisomal functions are impaired. Most of the functions known to take place in peroxisomes have to do with lipids. Indeed, peroxisomes are capable of 1. fatty acid beta-oxidation 2. fatty acid alpha-oxidation 3. synthesis of cholesterol and other isoprenoids 4. ether-phospholipid synthesis and 5. biosynthesis of polyunsaturated fatty acids. In Chapters 2-6 we will discuss the functional organization and enzymology of these pathways in detail. Furthermore, attention is paid to the permeability properties of peroxisomes with special emphasis on recent studies which suggest that peroxisomes are closed structures containing specific membrane proteins for transport of metabolites. Finally, the disorders of peroxisomal lipid metabolism will be discussed.
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Affiliation(s)
- R J Wanders
- Department of Clinical Chemistry, University of Amsterdam, The Netherlands
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Verhoeven NM, Roe DS, Kok RM, Wanders RJ, Jakobs C, Roe CR. Phytanic acid and pristanic acid are oxidized by sequential peroxisomal and mitochondrial reactions in cultured fibroblasts. J Lipid Res 1998. [DOI: 10.1016/s0022-2275(20)34204-8] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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