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Wang N, Peng H, Yang C, Guo W, Wang M, Li G, Liu D. Metabolic Engineering of Model Microorganisms for the Production of Xanthophyll. Microorganisms 2023; 11:1252. [PMID: 37317226 DOI: 10.3390/microorganisms11051252] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/19/2023] [Accepted: 05/06/2023] [Indexed: 06/16/2023] Open
Abstract
Xanthophyll is an oxidated version of carotenoid. It presents significant value to the pharmaceutical, food, and cosmetic industries due to its specific antioxidant activity and variety of colors. Chemical processing and conventional extraction from natural organisms are still the main sources of xanthophyll. However, the current industrial production model can no longer meet the demand for human health care, reducing petrochemical energy consumption and green sustainable development. With the swift development of genetic metabolic engineering, xanthophyll synthesis by the metabolic engineering of model microorganisms shows great application potential. At present, compared to carotenes such as lycopene and β-carotene, xanthophyll has a relatively low production in engineering microorganisms due to its stronger inherent antioxidation, relatively high polarity, and longer metabolic pathway. This review comprehensively summarized the progress in xanthophyll synthesis by the metabolic engineering of model microorganisms, described strategies to improve xanthophyll production in detail, and proposed the current challenges and future efforts needed to build commercialized xanthophyll-producing microorganisms.
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Affiliation(s)
- Nan Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Huakang Peng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Caifeng Yang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Wenfang Guo
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Mengqi Wang
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Gangqiang Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Dehu Liu
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China
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Schwarzhans JP, Luttermann T, Geier M, Kalinowski J, Friehs K. Towards systems metabolic engineering in Pichia pastoris. Biotechnol Adv 2017; 35:681-710. [DOI: 10.1016/j.biotechadv.2017.07.009] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 07/20/2017] [Accepted: 07/24/2017] [Indexed: 12/30/2022]
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Wangler MF, Chao YH, Bayat V, Giagtzoglou N, Shinde AB, Putluri N, Coarfa C, Donti T, Graham BH, Faust JE, McNew JA, Moser A, Sardiello M, Baes M, Bellen HJ. Peroxisomal biogenesis is genetically and biochemically linked to carbohydrate metabolism in Drosophila and mouse. PLoS Genet 2017; 13:e1006825. [PMID: 28640802 PMCID: PMC5480855 DOI: 10.1371/journal.pgen.1006825] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 05/16/2017] [Indexed: 01/07/2023] Open
Abstract
Peroxisome biogenesis disorders (PBD) are a group of multi-system human diseases due to mutations in the PEX genes that are responsible for peroxisome assembly and function. These disorders lead to global defects in peroxisomal function and result in severe brain, liver, bone and kidney disease. In order to study their pathogenesis we undertook a systematic genetic and biochemical study of Drosophila pex16 and pex2 mutants. These mutants are short-lived with defects in locomotion and activity. Moreover these mutants exhibit severe morphologic and functional peroxisomal defects. Using metabolomics we uncovered defects in multiple biochemical pathways including defects outside the canonical specialized lipid pathways performed by peroxisomal enzymes. These included unanticipated changes in metabolites in glycolysis, glycogen metabolism, and the pentose phosphate pathway, carbohydrate metabolic pathways that do not utilize known peroxisomal enzymes. In addition, mutant flies are starvation sensitive and are very sensitive to glucose deprivation exhibiting dramatic shortening of lifespan and hyperactivity on low-sugar food. We use bioinformatic transcriptional profiling to examine gene co-regulation between peroxisomal genes and other metabolic pathways and we observe that the expression of peroxisomal and carbohydrate pathway genes in flies and mouse are tightly correlated. Indeed key steps in carbohydrate metabolism were found to be strongly co-regulated with peroxisomal genes in flies and mice. Moreover mice lacking peroxisomes exhibit defective carbohydrate metabolism at the same key steps in carbohydrate breakdown. Our data indicate an unexpected link between these two metabolic processes and suggest metabolism of carbohydrates could be a new therapeutic target for patients with PBD.
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Affiliation(s)
- Michael F. Wangler
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, United States of America
- Texas Children’s Hospital, Houston TX, United States of America
- Program in Developmental Biology, BCM, Houston, TX, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital (TCH), Houston, TX, United States of America
| | - Yu-Hsin Chao
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, United States of America
| | - Vafa Bayat
- Program in Developmental Biology, BCM, Houston, TX, United States of America
| | - Nikolaos Giagtzoglou
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, United States of America
| | - Abhijit Babaji Shinde
- KU Leuven, Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, Leuven, Belgium
| | - Nagireddy Putluri
- Department of Molecular and Cellular Biology, BCM, Houston, TX, United States of America
| | - Cristian Coarfa
- Department of Molecular and Cellular Biology, BCM, Houston, TX, United States of America
| | - Taraka Donti
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, United States of America
| | - Brett H. Graham
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, United States of America
| | - Joseph E. Faust
- Department of BioSciences, Rice University, Houston TX, United States of America
| | - James A. McNew
- Department of BioSciences, Rice University, Houston TX, United States of America
| | - Ann Moser
- Kennedy Krieger Institute, Baltimore MD, United States of America
| | - Marco Sardiello
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, United States of America
- Program in Developmental Biology, BCM, Houston, TX, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital (TCH), Houston, TX, United States of America
| | - Myriam Baes
- KU Leuven, Laboratory of Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, Leuven, Belgium
| | - Hugo J. Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, United States of America
- Texas Children’s Hospital, Houston TX, United States of America
- Program in Developmental Biology, BCM, Houston, TX, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital (TCH), Houston, TX, United States of America
- Howard Hughes Medical Institute, Houston, TX, United States of America
- Department of Neuroscience, BCM, Houston, TX, United States of America
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Untethering the nuclear envelope and cytoskeleton: biologically distinct dystonias arising from a common cellular dysfunction. Int J Cell Biol 2012; 2012:634214. [PMID: 22611399 PMCID: PMC3352338 DOI: 10.1155/2012/634214] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 12/12/2011] [Accepted: 01/08/2012] [Indexed: 12/31/2022] Open
Abstract
Most cases of early onset DYT1 dystonia in humans are caused by a GAG deletion in the TOR1A gene leading to loss of a glutamic acid (ΔE) in the torsinA protein, which underlies a movement disorder associated with neuronal dysfunction without apparent neurodegeneration. Mutation/deletion of the gene (Dst) encoding dystonin in mice results in a dystonic movement disorder termed dystonia musculorum, which resembles aspects of dystonia in humans. While torsinA and dystonin proteins do not share modular domain architecture, they participate in a similar function by modulating a structural link between the nuclear envelope and the cytoskeleton in neuronal cells. We suggest that through a shared interaction with the nuclear envelope protein nesprin-3α, torsinA and the neuronal dystonin-a2 isoform comprise a bridge complex between the outer nuclear membrane and the cytoskeleton, which is critical for some aspects of neuronal development and function. Elucidation of the overlapping roles of torsinA and dystonin-a2 in nuclear/endoplasmic reticulum dynamics should provide insights into the cellular mechanisms underlying the dystonic phenotype.
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Optimization of the Trichoderma reesei endo-1,4-beta-xylanase production by recombinant Pichia pastoris. Biochem Eng J 2010. [DOI: 10.1016/j.bej.2010.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Sonnhammer EL, Wolfsberg TG. Identification of motifs in protein sequences. CURRENT PROTOCOLS IN CELL BIOLOGY 2008; Appendix 1:Appendix 1C. [PMID: 18228275 DOI: 10.1002/0471143030.cba01cs00] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This brief appendix serves as a guide for the analysis of functional motifs in proteins. Several database search engines that can be accessed via the World Wide Web are described. Such computerized searches have become the preferred method to scan large sequence and motif databases, as the searches are efficient and the databases are updated frequently. A short list of sorting signals is also included, since these motifs often cannot be predicted reliably by a computer search.
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Affiliation(s)
- E L Sonnhammer
- Center for Genomics Research, Karolinska Institutet, Stockholm, Sweden
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Abstract
Peroxisomes are essential organelles that may be involved in various functions, dependent on organism, cell type, developmental stage of the cell, and the environment. Until recently, peroxisomes were viewed as a class of static organelles that developed by growth and fission from pre-existing organelles. Recent observations have challenged this view by providing evidence that peroxisomes may be part of the endomembrane system and constitute a highly dynamic population of organelles that arises and is removed upon environmental demands. Additionally, evidence is now accumulating that peroxisomes may arise by alternative methods. This review summarizes relevant recent data on this subject. In addition, the progress in the understanding of the principles of the peroxisomal matrix protein import machinery is discussed.
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Affiliation(s)
- Marten Veenhuis
- Eukaryotic Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute (GBB), University of Groningen, NL-9750 AA Haren, The Netherlands.
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Chen C, Wang Q, Fang X, Xu Q, Chi C, Gu J. Roles of phytanoyl-CoA alpha-hydroxylase in mediating the expression of human coagulation factor VIII. J Biol Chem 2001; 276:46340-6. [PMID: 11574539 DOI: 10.1074/jbc.m106124200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The coagulation factor VIII (FVIII) is the coagulation factor deficient in the X-chromosome-linked bleeding disorder hemophilia A. Previous transfection studies demonstrated that factor VIII was 10-100-fold less efficiently expressed than the homologous coagulation factor, factor V. To investigate the regulatory mechanisms of FVIII synthesis and secretion, we used the yeast two-hybrid system as an approach to search for proteins that associated with FVIII. The A2 domain (337-740 amino acids) of factor VIII (FVIII-A2) was used as a bait and phytanoyl-CoA alpha-hydroxylase (PAHX) was identified as a binding protein of FVIII-A2. PAHX had potential to interact with the residues 373-508 within the A2 domain, but not with A1 and A3 (the homologous domains of A2). The interaction between the A2 domain and PAHX was independent of the type 2 peroxisomal targeting signal (PTS2) of PAHX. Overexpression of PAHX in FVIII-produced cells decreased the expression of FVIII by about 70%. The elevated expression of von Willebrand factor had no effect on the suppression of FVIII secretion by PAHX. Expression of the green fluorescent PAHX fusion protein in SMMC-7721 cells affected the intracellular trafficking of FVIII-A2. These results suggested that the interaction between PAHX and FVIII-A2 was in part responsible for the low-level expression of factor VIII.
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Affiliation(s)
- C Chen
- Gene Research Center, Medical Center of Fudan University, Shanghai 200032, China
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Abstract
Long-chain fatty acids are a vital metabolic energy source and are building blocks of membrane lipids. The yeast Saccharomyces cerevisiae is a valuable model system for elucidation of gene-function relationships in such eukaryotic processes as fatty acid metabolism. Yeast degrades fatty acids only in the peroxisome, and recently, genes encoding core and auxiliary enzymes of peroxisomal beta-oxidation have been identified. Mechanisms involved in fatty acid induction of gene expression have been described, and novel fatty acid-responsive genes have been discovered via yeast genome analysis. In addition, a number of genes essential for synthesis of the variety of fatty acids in yeast have been cloned. Advances in understanding such processes in S. cerevisiae will provide helpful insights to functional genomics approaches in more complex organisms.
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Affiliation(s)
- P J Trotter
- The Division of Nutritional Sciences and the Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, Texas 78712, USA.
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van Roermund CW, Drissen R, van Den Berg M, Ijlst L, Hettema EH, Tabak HF, Waterham HR, Wanders RJ. Identification of a peroxisomal ATP carrier required for medium-chain fatty acid beta-oxidation and normal peroxisome proliferation in Saccharomyces cerevisiae. Mol Cell Biol 2001; 21:4321-9. [PMID: 11390660 PMCID: PMC87092 DOI: 10.1128/mcb.21.13.4321-4329.2001] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2000] [Accepted: 04/04/2001] [Indexed: 11/20/2022] Open
Abstract
We have characterized the role of YPR128cp, the orthologue of human PMP34, in fatty acid metabolism and peroxisomal proliferation in Saccharomyces cerevisiae. YPR128cp belongs to the mitochondrial carrier family (MCF) of solute transporters and is localized in the peroxisomal membrane. Disruption of the YPR128c gene results in impaired growth of the yeast with the medium-chain fatty acid (MCFA) laurate as a single carbon source, whereas normal growth was observed with the long-chain fatty acid (LCFA) oleate. MCFA but not LCFA beta-oxidation activity was markedly reduced in intact ypr128cDelta mutant cells compared to intact wild-type cells, but comparable activities were found in the corresponding lysates. These results imply that a transport step specific for MCFA beta-oxidation is impaired in ypr128cDelta cells. Since MCFA beta-oxidation in peroxisomes requires both ATP and CoASH for activation of the MCFAs into their corresponding coenzyme A esters, we studied whether YPR128cp is an ATP carrier. For this purpose we have used firefly luciferase targeted to peroxisomes to measure ATP consumption inside peroxisomes. We show that peroxisomal luciferase activity was strongly reduced in intact ypr128cDelta mutant cells compared to wild-type cells but comparable in lysates of both cell strains. We conclude that YPR128cp most likely mediates the transport of ATP across the peroxisomal membrane.
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Affiliation(s)
- C W van Roermund
- University of Amsterdam, Academic Medical Centre, Department of Clinical Chemistry, Emma Children's Hospital, 1100 DE Amsterdam, The Netherlands
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11
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Johnson MA, Snyder WB, Cereghino JL, Veenhuis M, Subramani S, Cregg JM. Pichia pastoris Pex14p, a phosphorylated peroxisomal membrane protein, is part of a PTS-receptor docking complex and interacts with many peroxins. Yeast 2001; 18:621-41. [PMID: 11329173 DOI: 10.1002/yea.711] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The peroxisomal protein import machinery plays a central role in the assembly of this organelle in all eukaryotes. Genes encoding components of this machinery, termed peroxins or Pex proteins, have been isolated and characterized in several yeast species and in mammals, including humans. Here we report on one of these components, Pex14p, from the methylotrophic yeast Pichia pastoris. Work in other organisms has shown that Pex14p is located on the cytoplasmic surface of the peroxisomal membrane and binds peroxisomal targeting signal (PTS) receptors carrying proteins bound for the peroxisomal matrix, results that have led to the hypothesis that Pex14p is a receptor-docking protein. P. pastoris Pex14p (PpPex14p) behaves like an integral membrane protein, with its C-terminus exposed on the cytosolic side of the peroxisomal membrane. PpPex14p complexes with many peroxins, including Pex3p (Snyder et al., 1999b), Pex5p, Pex7p, Pex13p, Pex17p, itself, and a previously unreported peroxin, Pex8p. A portion of Pex14p is phosphorylated, but both phosphorylated and unphosphorylated forms of Pex14p interact with several peroxins. The interactions between Pex14p and other peroxins provide clues regarding the function of Pex14p in peroxisomal protein import.
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Affiliation(s)
- M A Johnson
- Department of Biochemistry and Molecular Biology, Oregon Graduate Institute of Science and Technology, 20000 N.W. Walker Road, Beaverton, OR 97006-8921, USA
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12
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Abstract
In yeast, peroxisomes are the site of specific catabolic pathways that characteristically include hydrogen peroxide producing oxidases and catalase. During the last 10 years, much progress has been made in unravelling the molecular mechanisms involved in the biogenesis of this organelle. At present, 23 different genes (PEX genes) have been identified that are involved in different aspects of peroxisome biogenesis (e.g., proliferation, formation of the peroxisomal membrane, import of matrix proteins). The principles of peroxisome degradation are still much less understood. Recently, the first yeast mutants affected in this process have become available and used to clone corresponding genes by functional complementation. In this paper, an overview is presented of the research on yeast peroxisomes, focusing on recent achievements in the molecular aspects of peroxisome development, function, and turnover.
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Affiliation(s)
- M Veenhuis
- Eukaryotic Microbiology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, P.O. Box 14, 9750 AA Haren, The Netherlands.
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Cancio I, Cajaraville MP. Cell biology of peroxisomes and their characteristics in aquatic organisms. INTERNATIONAL REVIEW OF CYTOLOGY 2000; 199:201-93. [PMID: 10874580 DOI: 10.1016/s0074-7696(00)99005-3] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
The general characteristics of peroxisomes in different organisms, including aquatic organisms such as fish, crustaceans, and mollusks, are reviewed, with special emphasis on different aspects of the organelle biogenesis and mechanistic aspects of peroxisome proliferation. Peroxisome proliferation and peroxisomal enzyme inductions elicited by xenobiotics or physiological conditions have become useful tools to study the mechanisms of peroxisome biogenesis. During peroxisome proliferation, the induction of peroxisomal proteins is heterogeneous, enzymes that show increased activity being involved in different aspects of lipid homeostasis. The process of peroxisome biogenesis is coordinately triggered by a whole array of structurally dissimilar compounds known as peroxisome proliferators, and investigating the effect of some of these compounds that commonly appear as pollutants in the environment on the peroxisomes of aquatic animals inhabiting marine and estuarine habitats seems interesting. It is also important to determine whether peroxisome proliferation in these animals is a phenomenon that might occur under normal physiological or season-related conditions and plays a metabolic or functional role. This would help set the basis for understanding the process of peroxisome biogenesis in aquatic animals.
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Affiliation(s)
- I Cancio
- Zoologia eta Animali Zelulen Dinamika Saila, Euskal Herriko Unibertsitatea, Bilbo/Basque Country, Spain
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Götte M, Lazar T, Yoo JS, Scheglmann D, Gallwitz D. The full complement of yeast Ypt/Rab-GTPases and their involvement in exo- and endocytic trafficking. Subcell Biochem 2000; 34:133-73. [PMID: 10808333 DOI: 10.1007/0-306-46824-7_4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- M Götte
- Department of Molecular Genetics, Max-Planck-Institute for Biophysical Chemistry, Göttingen, Germany
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Ghaedi K, Tamura S, Okumoto K, Matsuzono Y, Fujiki Y. The peroxin pex3p initiates membrane assembly in peroxisome biogenesis. Mol Biol Cell 2000; 11:2085-102. [PMID: 10848631 PMCID: PMC14905 DOI: 10.1091/mbc.11.6.2085] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Rat cDNA encoding a 372-amino-acid peroxin was isolated, primarily by functional complementation screening, using a peroxisome-deficient Chinese hamster ovary cell mutant, ZPG208, of complementation group 17. The deduced primary sequence showed approximately 25% amino acid identity with the yeast Pex3p, thereby we termed this cDNA rat PEX3 (RnPEX3). Human and Chinese hamster Pex3p showed 96 and 94% identity to rat Pex3p and had 373 amino acids. Pex3p was characterized as an integral membrane protein of peroxisomes, exposing its N- and C-terminal parts to the cytosol. A homozygous, inactivating missense mutation, G to A at position413, in a codon (GGA) for Gly(138) and resulting in a codon (GAA) for Glu was the genetic cause of peroxisome deficiency of complementation group 17 ZPG208. The peroxisome-restoring activity apparently required the full length of Pex3p, whereas its N-terminal part from residues 1 to 40 was sufficient to target a fusion protein to peroxisomes. We also demonstrated that Pex3p binds the farnesylated peroxisomal membrane protein Pex19p. Moreover, upon expression of PEX3 in ZPG208, peroxisomal membrane vesicles were assembled before the import of soluble proteins such as PTS2-tagged green fluorescent protein. Thus, Pex3p assembles membrane vesicles before the matrix proteins are translocated.
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Affiliation(s)
- K Ghaedi
- Department of Biology, Graduate School of Science, Kyushu University, Fukuoka 812-8581, Japan
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Musser SM, Theg SM. Characterization of the early steps of OE17 precursor transport by the thylakoid DeltapH/Tat machinery. EUROPEAN JOURNAL OF BIOCHEMISTRY 2000; 267:2588-98. [PMID: 10785379 DOI: 10.1046/j.1432-1327.2000.01269.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In order to probe the structure and protein translocation function of the thylakoid Tat machinery, a 25-residue C-terminal extension containing a 13-residue in vivo biotinylation tag and a 6x His tag was added to a mutant precursor of the 17-kDa subunit of the oxygen-evolving complex to form pOE17(C)-BioHis. When avidin was attached to biotinylated precursor in situ, the precursor-avidin complex was neither imported nor did it form a membrane-spanning translocation intermediate. It did, however, competitively inhibit the translocation of unbiotinylated precursor with an apparent KI unaffected by avidin. It is shown that the precursor protein achieves a stable folded structure upon dilution from urea, suggesting that the avidin-induced inhibition of transport results from a folding-induced proximity of N-terminal and C-terminal domains. It is further demonstrated that the majority of precursor rapidly binds to the thylakoid membrane, remaining import competent and yet undissociable by high salt or high pH treatment at ice temperature. The membrane binding event is unaffected by avidin. Import kinetics reveal that nonproton motive force-driven transport steps make up a major fraction of the transport time. These observations suggest that the N-terminal presequence on the avidin-bound precursor is available for membrane binding and initial recognition by the transport machinery, but the attached avidin signals the machinery that the precursor is an incorrectly configured substrate and thus import is aborted. Consequently, the DeltapH/Tat machinery's proofreading mechanism must operate after precursor recognition but before the committed step in transport.
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Affiliation(s)
- S M Musser
- Section of Plant Biology, University of California, Davis, USA
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17
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Smith RL, Johnson AD. A sequence resembling a peroxisomal targeting sequence directs the interaction between the tetratricopeptide repeats of Ssn6 and the homeodomain of alpha 2. Proc Natl Acad Sci U S A 2000; 97:3901-6. [PMID: 10759558 PMCID: PMC18114 DOI: 10.1073/pnas.070506797] [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: 11/18/2022] Open
Abstract
The tetratricopeptide repeat (TPR) is a 34-aa sequence motif, typically found in tandem clusters, that occurs in proteins of bacteria, archea, and eukaryotes. TPRs interact with other proteins, although few details on TPR-protein interactions are known. In this paper we show that a portion of a loop in the homeodomain of the DNA-binding protein alpha2 is required for its recognition by the TPRs of the corepressor Ssn6. The amino acid sequence of this loop is similar to the sequences recognized by the TPRs of an entirely different protein, Pex5, which directs peroxisomal import. We further show that alpha2 can be made to bind specifically in vitro to the TPRs of Pex5 and that a point mutation that disrupts the alpha2-Ssn6 interaction also disrupts the alpha2-Pex5 interaction. These results demonstrate that two different TPR proteins recognize their target by a similar mechanism, raising the possibility that other TPR-target interactions could occur through the same means.
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Affiliation(s)
- R L Smith
- Department of Biochemistry and Biophysics, University of California, Box 0414, San Francisco, CA 94143, USA
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Hutchins MU, Veenhuis M, Klionsky DJ. Peroxisome degradation in Saccharomyces cerevisiae is dependent on machinery of macroautophagy and the Cvt pathway. J Cell Sci 1999; 112 ( Pt 22):4079-87. [PMID: 10547367 DOI: 10.1242/jcs.112.22.4079] [Citation(s) in RCA: 149] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Organelle biogenesis and turnover are necessary to maintain biochemical processes that are appropriate to the needs of the eukaryotic cell. Specific degradation of organelles in response to changing environmental cues is one aspect of achieving proper metabolic function. For example, the yeast Saccharomyces cerevisiae adjusts the level of peroxisomes in response to differing nutritional sources. When cells are grown on oleic acid as the sole carbon source, peroxisome biogenesis is induced. Conversely, a subsequent shift to glucose-rich or nitrogen-limiting conditions results in peroxisome degradation. The degradation process, pexophagy, requires the activity of vacuolar hydrolases. In addition, peroxisome degradation is specific. Analyses of cellular marker proteins indicate that peroxisome degradation under these conditions occurs more rapidly and to a greater extent than mitochondrial, Golgi, or cytosolic protein delivery to the vacuole by the non-selective autophagy pathway. To elucidate the molecular mechanism of selective peroxisome degradation, we examined pexophagy in mutants that are defective in autophagy (apg) and the selective targeting of aminopeptidase I to the vacuole by the cytoplasm to vacuole targeting (Cvt) pathway. Inhibition of peroxisome degradation in cvt and apg mutants indicates that these pathways overlap and that peroxisomes are delivered to the vacuole by a mechanism that utilizes protein components of the Cvt/autophagy pathways.
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Affiliation(s)
- M U Hutchins
- University of California, Davis, Section of Microbiology, Davis, CA 95616, USA
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Gouveia AM, Reguenga C, Oliveira ME, Eckerskorn C, Sá-Miranda C, Azevedo JE. Alkaline density gradient floatation of membranes: polypeptide composition of the mammalian peroxisomal membrane. Anal Biochem 1999; 274:270-7. [PMID: 10527525 DOI: 10.1006/abio.1999.4281] [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: 11/22/2022]
Abstract
A method for purification of the peroxisomal membrane from rat liver is described. The procedure consists of floating the (contaminated) peroxisomal membranes through an alkaline sucrose density gradient. A good resolution between the peroxisomal membrane and other membrane systems is achieved. Using these floated peroxisomal membranes we have determined that only 7.8 +/- 0.9% of the total peroxisomal protein is alkali resistant. The polypeptide composition of these highly pure peroxisomal membranes was analyzed by SDS-PAGE. Bands corresponding to polypeptides with apparent molecular masses of 15, 18, 22, 24, 26, 29, 35, 36, 38, 40, 52, 55, 70, 74-77, and 88 kDa are detected upon Coomassie blue staining of polyacrylamide gels. The identity of several of these polypeptides was determined by N-terminal sequencing and Western blotting analysis.
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Affiliation(s)
- A M Gouveia
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
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20
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Abstract
Peroxisomes are organelles that confine an important set of enzymes within their single membrane boundaries. In man, a wide variety of genetic disorders is caused by loss of peroxisome function. In the most severe cases, the clinical phenotype indicates that abnormalities begin to appear during embryological development. In less severe cases, the quality of life of adults is affected. Research on yeast model systems has contributed to a better understanding of peroxisome formation and maintenance. This framework of knowledge has made it possible to understand the molecular basis of most of the peroxisome biogenesis disorders. Interestingly, most peroxisome biogenesis disorders are caused by a failure to target peroxisomal proteins to the organellar matrix or membrane, which classifies them as protein targeting diseases. Here we review recent fundamental research on peroxisomal protein targeting and discuss a few burning questions in the field concerning the origin of peroxisomes.
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Affiliation(s)
- E H Hettema
- Department of Biochemistry, Academic Medical Centre, Meibergdreef 15, 1105 AZ, Amsterdam, Netherlands
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21
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Soukupova M, Sprenger C, Gorgas K, Kunau WH, Dodt G. Identification and characterization of the human peroxin PEX3. Eur J Cell Biol 1999; 78:357-74. [PMID: 10430017 DOI: 10.1016/s0171-9335(99)80078-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
The biogenesis of peroxisomes requires the interaction of several peroxins, encoded by PEX genes and is well conserved between yeast and humans. We have cloned the human cDNA of PEX3 based on its homology to different yeast PEX3 genes. The deduced peroxin HsPEX3 is a peroxisomal membrane protein with a calculated molecular mass of 42.1 kDa. We created N- and C-terminal tagged PEX3 to assay its topology at the peroxisomal membrane by immunofluorescence microscopy. Our results and the one predicted transmembrane spanning region are in line with the assumption that H sPEX3 is an integral peroxisomal membrane protein with the N-terminus inside the peroxisome and the C-terminus facing the cytoplasm. The farnesylated peroxisomal membrane protein PEX19 interacts with HsPEX3 in a mammalian two-hybrid assay in human fibroblasts. The physical interaction could be confirmed by coimmunoprecipitation of the two in vitro transcribed and translated proteins. To address the targeting of PEX3 to the peroxisomal membrane, the expression of different N- and C-terminal PEX3 truncations fused to green fluorescent protein (GFP) was investigated in human fibroblasts. The N-terminal 33 amino acids of PEX3 were necessary and sufficient to direct the reporter protein GFP to peroxisomes and seemed to be integrated into the peroxisomal membrane. The expression of a 1-16 PEX3-GFP fusion protein did not result in a peroxisomal localization, but interestingly, this and several other truncated PEX3 fusion proteins were also localized to tubular and/or vesicular structures representing mitochondria.
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Affiliation(s)
- M Soukupova
- Institut für Physiologische Chemie, Systembiochemie, Ruhr-Universität Bochum, Germany
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22
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Trotter PJ, Hagerman RA, Voelker DR. A yeast strain defective in oleic acid utilization has a mutation in the RML2 gene. BIOCHIMICA ET BIOPHYSICA ACTA 1999; 1438:223-38. [PMID: 10320805 DOI: 10.1016/s1388-1981(99)00054-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The molecular mechanisms of cellular long-chain fatty acid assimilation and its regulation remain unclear. In an attempt to identify essential mediators of these processes, we have isolated mutant strains of the yeast Saccharomyces cerevisiae unable to utilize oleic acid as sole carbon source, while retaining the ability to utilize acetate. These strains are then subjected to several secondary screening assays to identify mutants of interest. Here we describe a mutant (denoted fat21) that, despite a temperature-sensitive inability to utilize oleic acid as sole carbon source, displays no general defect in oleic acid uptake or incorporation of oleic acid into glycerolipids. Oxidation of acetate after growth in acetate medium is increased similarly in the mutant and parent strains. Oleic acid beta-oxidation in acetate grown cells is also comparable between strains. Induction of oleic acid oxidation following exposure to oleic acid is, however, defective in the fat21 mutant. The fat21 mutant allele displays conditional synthetic lethality in combination with a null allele of the OLE1 gene, which encodes Delta9-desaturase and is required for proper mitochondrial segregation. Clones capable of complementing the fat21 defect contained the RML2 gene, encoding a yeast mitochondria ribosomal protein. Segregation analysis and gene replacement experiments demonstrate that RML2 is the gene defective in the fat21 mutant. These observations of a defect in a mitochondrial protein differentially affecting the adaptation to oleic acid and acetate as carbon sources suggest that the phenotype of fat21 is associated with a novel pathway of mitochondrial-nuclear-peroxisomal communication.
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Affiliation(s)
- P J Trotter
- Division of Nutritional Sciences and Institute for Cellular and Molecular Biology, A4800, MBB 2.148, The University of Texas at Austin, Austin, TX 78712, USA.
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23
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Ghaedi K, Itagaki A, Toyama R, Tamura S, Matsumura T, Kawai A, Shimozawa N, Suzuki Y, Kondo N, Fujiki Y. Newly identified Chinese hamster ovary cell mutants defective in peroxisome assembly represent complementation group A of human peroxisome biogenesis disorders and one novel group in mammals. Exp Cell Res 1999; 248:482-8. [PMID: 10222139 DOI: 10.1006/excr.1999.4412] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We isolated peroxisome biogenesis-defective mutants from rat PEX2-transformed Chinese hamster ovary (CHO) cells, using the 9-(1'-pyrene)nonanol/ultraviolet method. A total of 18 mutant cell clones showing cytosolic localization of catalase were isolated. By complementation group (CG) analysis by means of PEX cDNA transfection and cell fusion, cell mutants, ZP124 and ZP126, were found to belong to two novel CGs of CHO mutants. Mutants, ZP135 and ZP167, were also classified to the same CG as ZP124. Further cell fusion analysis using 12 CGs fibroblasts from patients with peroxisome deficiency disorders such as Zellweger syndrome revealed that ZP124 belonged to human CG-A, the same group as CG-VIII in the United States. ZP126 could not be classified to any of human and CHO CGs. These mutants also showed typical peroxisome assembly-defective phenotypes such as severe loss of catalase latency and impaired biogenesis of peroxisomal enzymes. Collectively, ZP124 represents CG-A, and ZP126 is in a newly identified CG distinct from the 14 mammalian CGs previously characterized.
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Affiliation(s)
- K Ghaedi
- Faculty of Science, Kyushu University, Fukuoka, 812-8581, Japan
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24
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Ghaedi K, Kawai A, Okumoto K, Tamura S, Shimozawa N, Suzuki Y, Kondo N, Fujiki Y. Isolation and characterization of novel peroxisome biogenesis-defective Chinese hamster ovary cell mutants using green fluorescent protein. Exp Cell Res 1999; 248:489-97. [PMID: 10222140 DOI: 10.1006/excr.1999.4413] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We developed an improved method for isolation of peroxisome biogenesis-defective somatic animal cell mutants, using a combination of green fluorescent protein (GFP) expression and the 9-(1'-pyrene)nonanol/ultraviolet (P9OH/UV) selection method. We used TKaG1 and TKaG2 cells, the wild-type Chinese hamster ovary (CHO) cells, CHO-K1, that had been stably transfected with cDNAs each encoding rat Pex2p as well as GFP tagged at the C-terminus with peroxisome targeting signal type 1 (PTS1) or N-terminally PTS2-tagged GFP. P9OH/UV-resistant cell colonies were examined for intracellular location of GFP on unfixed cells, by fluorescence microscopy. Seven each of the mutant cell clones isolated from TKaG1 and TKaG2 showed cytosolic GFP-PTS1 and PTS2-GFP, respectively, indicating the defect in peroxisome assembly. By transfection of PEX2, PEX5, PEX6, and PEX12 cDNAs and cell fusion analysis between the CHO cell mutants, five different complementation groups (CGs) were identified. Two mutant clones, ZPG207 and ZPG208, belonged to novel CGs. Further CG analysis using fibroblasts from patients with peroxisome biogenesis disorders, including rhizomelic chondrodysplasia punctata (RCDP), revealed that ZPG208 belonged to none of human CGs. ZPG207 was classified into the same CG as RCDP. Taken together, ZPG208 is in a newly identified, the 12th, CG in peroxisome-deficient CHO mutants reported to date and represents a novel mammalian CG.
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Affiliation(s)
- K Ghaedi
- Faculty of Science, Kyushu University, Fukuoka, 812-8581, Japan
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25
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Johnson MA, Waterham HR, Ksheminska GP, Fayura LR, Cereghino JL, Stasyk OV, Veenhuis M, Kulachkovsky AR, Sibirny AA, Cregg JM. Positive selection of novel peroxisome biogenesis-defective mutants of the yeast Pichia pastoris. Genetics 1999; 151:1379-91. [PMID: 10101164 PMCID: PMC1460572 DOI: 10.1093/genetics/151.4.1379] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have developed two novel schemes for the direct selection of peroxisome-biogenesis-defective (pex) mutants of the methylotrophic yeast Pichia pastoris. Both schemes take advantage of our observation that methanol-induced pex mutants contain little or no alcohol oxidase (AOX) activity. AOX is a peroxisomal matrix enzyme that catalyzes the first step in the methanol-utilization pathway. One scheme utilizes allyl alcohol, a compound that is not toxic to cells but is oxidized by AOX to acrolein, a compound that is toxic. Exposure of mutagenized populations of AOX-induced cells to allyl alcohol selectively kills AOX-containing cells. However, pex mutants without AOX are able to grow. The second scheme utilizes a P. pastoris strain that is defective in formaldehyde dehydrogenase (FLD), a methanol pathway enzyme required to metabolize formaldehyde, the product of AOX. AOX-induced cells of fld1 strains are sensitive to methanol because of the accumulation of formaldehyde. However, fld1 pex mutants, with little active AOX, do not efficiently oxidize methanol to formaldehyde and therefore are not sensitive to methanol. Using these selections, new pex mutant alleles in previously identified PEX genes have been isolated along with mutants in three previously unidentified PEX groups.
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Affiliation(s)
- M A Johnson
- Department of Biochemistry and Molecular Biology, Oregon Graduate Institute of Science and Technology, Portland, Oregon 97291-1000, USA
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26
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Chambraud B, Radanyi C, Camonis JH, Rajkowski K, Schumacher M, Baulieu EE. Immunophilins, Refsum disease, and lupus nephritis: the peroxisomal enzyme phytanoyl-COA alpha-hydroxylase is a new FKBP-associated protein. Proc Natl Acad Sci U S A 1999; 96:2104-9. [PMID: 10051602 PMCID: PMC26744 DOI: 10.1073/pnas.96.5.2104] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
FKBP52 (FKBP59, FKBP4) is a "macro" immunophilin that, although sharing high structural and functional homologies in its amino-terminal domain with FKBP12 (FKBP1), does not have immunosuppressant activity when complexed with FK506, unlike FKBP12. To investigate the physiological function of FKBP52, we used the yeast two-hybrid system as an approach to find its potential protein partners and, from that, its cellular role. This methodology, which already has allowed us to find the FK506-binding protein (FKBP)-associated protein FAP48, also led to the detection of another FKBP-associated protein. Determination of the sequence of this protein permitted its identification as phytanoyl-CoA alpha-hydroxylase (PAHX), a peroxisomal enzyme that so far was unknown as an FKBP-associated protein. Inactivation of this enzyme is responsible for Refsum disease in humans. The protein also corresponds to the mouse protein LN1, which could be involved in the progress of lupus nephritis. We show here that PAHX has the physical capacity to interact with the FKBP12-like domain of FKBP52, but not with FKBP12, suggesting that it is a particular and specific target of FKBP52. Whereas the binding of calcineurin to FKBP12 is potentiated by FK506, the specific association of PAHX and FKBP52 is maintained in the presence of FK506. This observation suggests that PAHX is a serious candidate for studying the cellular signaling pathway(s) involving FKBP52 in the presence of immunosuppressant drugs.
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Affiliation(s)
- B Chambraud
- Institut National de la Santé et de la Recherche Médicale (U488) and Collège de France, 80 rue du Général Leclerc, 94276 Bicêtre Cedex, France
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27
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Will GK, Soukupova M, Hong X, Erdmann KS, Kiel JA, Dodt G, Kunau WH, Erdmann R. Identification and characterization of the human orthologue of yeast Pex14p. Mol Cell Biol 1999; 19:2265-77. [PMID: 10022913 PMCID: PMC84019 DOI: 10.1128/mcb.19.3.2265] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/1998] [Accepted: 12/10/1998] [Indexed: 11/20/2022] Open
Abstract
Pex14p is a central component of the peroxisomal protein import machinery, which has been suggested to provide the point of convergence for PTS1- and PTS2-dependent protein import in yeast cells. Here we describe the identification of a human peroxisome-associated protein (HsPex14p) which shows significant similarity to the yeast Pex14p. HsPex14p is a carbonate-resistant peroxisomal membrane protein with its C terminus exposed to the cytosol. The N terminus of the protein is not accessible to exogenously added antibodies or protease and thus might protrude into the peroxisomal lumen. HsPex14p overexpression leads to the decoration of tubular structures and mislocalization of peroxisomal catalase to the cytosol. HsPex14p binds the cytosolic receptor for the peroxisomal targeting signal 1 (PTS1), a result consistent with a function as a membrane receptor in peroxisomal protein import. Homo-oligomerization of HsPex14p or interaction of the protein with the PTS2-receptor or HsPex13p was not observed. This distinguishes the human Pex14p from its counterpart in yeast cells and thus supports recent data suggesting that not all aspects of peroxisomal protein import are conserved between yeasts and humans. The role of HsPex14p in mammalian peroxisome biogenesis makes HsPEX14 a candidate PBD gene for being responsible for an unrecognized complementation group of human peroxisome biogenesis disorders.
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Affiliation(s)
- G K Will
- Institut für Physiologische Chemie, Ruhr-Universität Bochum, 44780 Bochum, Germany
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28
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Schliebs W, Saidowsky J, Agianian B, Dodt G, Herberg FW, Kunau WH. Recombinant human peroxisomal targeting signal receptor PEX5. Structural basis for interaction of PEX5 with PEX14. J Biol Chem 1999; 274:5666-73. [PMID: 10026185 DOI: 10.1074/jbc.274.9.5666] [Citation(s) in RCA: 147] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Import of matrix proteins into peroxisomes requires two targeting signal-specific import receptors, Pex5p and Pex7p, and their binding partners at the peroxisomal membrane, Pex13p and Pex14p. Several constructs of human PEX5 have been overexpressed and purified by affinity chromatography in order to determine functionally important interactions and provide initial structural information. Sizing chromatography and electron microscopy suggest that the two isoforms of the human PTS1 receptor, PEX5L and PEX5S, form homotetramers. Surface plasmon resonance analysis indicates that PEX5 binds to the N-terminal fragment of PEX14-(1-78) with a very high affinity in the low nanomolar range. Stable complexes between recombinant PEX14-(1-78) and both the full-length and truncated versions of PEX5 were formed in vitro. Analysis of these complexes revealed that PEX5 possesses multiple binding sites for PEX14, which appear to be distributed throughout its N-terminal half. Coincidentally, this part of the molecule is also responsible for oligomerization, whereas the C-terminal half with its seven tetratricopeptide repeats has been reported to bind PTS1-proteins. A pentapeptide motif that is reiterated seven times in PEX5 is proposed as a determinant for the interaction with PEX14.
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Affiliation(s)
- W Schliebs
- Institut für Physiologische Chemie, Ruhr-Universität Bochum, D-44780 Bochum, Germany
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29
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Neuwald AF, Aravind L, Spouge JL, Koonin EV. AAA+: A Class of Chaperone-Like ATPases Associated with the Assembly, Operation, and Disassembly of Protein Complexes. Genome Res 1999. [DOI: 10.1101/gr.9.1.27] [Citation(s) in RCA: 716] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Using a combination of computer methods for iterative database searches and multiple sequence alignment, we show that protein sequences related to the AAA family of ATPases are far more prevalent than reported previously. Among these are regulatory components of Lon and Clp proteases, proteins involved in DNA replication, recombination, and restriction (including subunits of the origin recognition complex, replication factor C proteins, MCM DNA-licensing factors and the bacterial DnaA, RuvB, and McrB proteins), prokaryotic NtrC-related transcription regulators, the Bacillus sporulation protein SpoVJ, Mg2+, and Co2+ chelatases, theHalobacterium GvpN gas vesicle synthesis protein, dynein motor proteins, TorsinA, and Rubisco activase. Alignment of these sequences, in light of the structures of the clamp loader δ′ subunit ofEscherichia coli DNA polymerase III and the hexamerization component of N-ethylmaleimide-sensitive fusion protein, provides structural and mechanistic insights into these proteins, collectively designated the AAA+ class. Whole-genome analysis indicates that this class is ancient and has undergone considerable functional divergence prior to the emergence of the major divisions of life. These proteins often perform chaperone-like functions that assist in the assembly, operation, or disassembly of protein complexes. The hexameric architecture often associated with this class can provide a hole through which DNA or RNA can be thread; this may be important for assembly or remodeling of DNA–protein complexes.
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30
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Flynn CR, Mullen RT, Trelease RN. Mutational analyses of a type 2 peroxisomal targeting signal that is capable of directing oligomeric protein import into tobacco BY-2 glyoxysomes. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1998; 16:709-20. [PMID: 10069077 DOI: 10.1046/j.1365-313x.1998.00344.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
In this study of the type 2 peroxisomal targeting signal (PTS2) pathway, we examined the apparent discontinuity and conservation of residues within the PTS2 nonapeptide and demonstrated that this topogenic signal is capable of directing heteromultimeric protein import in plant cells. Based on cumulative data showing that at least 26 unique, putative PTS2 nonapeptides occur within 12 diverse peroxisomal-destined proteins, the current (-R/K-L/V/I-X5-H/Q-L/A-) as well as the original (-R-L-X5-H/Q-L-) PTS2 motif appear to be oversimplified. To assess the functionality of residues within the motif, rat liver thiolase (rthio) and various chimeric chloramphenicol acetyltransferase (CAT) proteins were expressed transiently in suspension-cultured tobacco (Nicotiana tabaccum L.) cv Bright Yellow cells (BY-2), and their subcellular location was determined by immunofluoresence microscopy. Hemagglutinin (HA)-epitope-tagged-CAT subunits, lacking a PTS2 (CAT-HA), were 'piggybacked' into glyoxysomes by PTS2-bearing CAT subunits (rthio-CAT), whereas signal-depleted CAT-HA subunits that were modified to prevent oligomerization did not import into glyoxysomes. These results provided direct evidence that signal-depleted subunits imported into peroxisomes were targeted to the organelle as oligomers (heteromers) by a PTS2. Mutational analysis of residues within PTS2 nonapeptides revealed that a number of amino acid substitutions were capable of maintaining targeting function. Furthermore, functionality of residues within the PTS2 nonapeptide did not appear to require a context-specific environment conferred by adjacent residues. These results collectively suggest that the functional PTS2 is not solely defined as a sequence-specific motif, i.e. -R/K-X6-H/Q-A/L/F-, but defined also by its structural motif that is dependent upon the physiochemical properties of residues within the nonapeptide.
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Affiliation(s)
- C R Flynn
- Graduate Program in Molecular and Cellular Biology, Arizona State University, Tempe 85287-1601, USA
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31
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Vaz FM, van Gool S, Ofman R, Ijlst L, Wanders RJ. Carnitine biosynthesis: identification of the cDNA encoding human gamma-butyrobetaine hydroxylase. Biochem Biophys Res Commun 1998; 250:506-10. [PMID: 9753662 DOI: 10.1006/bbrc.1998.9343] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
gamma-Butyrobetaine hydroxylase (EC 1.14.11.1) is the last enzyme in the biosynthetic pathway of L-carnitine and catalyzes the formation of L-carnitine from gamma-butyrobetaine, a reaction dependent on alpha-ketoglutarate, Fe2+, and oxygen. We report the purification of the protein from rat liver to apparent homogeneity, which allowed N-terminal sequencing using Edman degradation. The obtained amino acid sequence was used to screen the expressed sequence tag database and led to the identification of a human cDNA containing an open reading frame of 1161 base pairs encoding a polypeptide of 387 amino acids with a predicted molecular weight of 44.7 kDa. Heterologous expression of the open reading frame in the yeast Saccharomyces cerevisiae confirmed that the cDNA encodes the human gamma-butyrobetaine hydroxylase. Northern blot analysis showed gamma-butyrobetaine hydroxylase expression in kidney (high), liver (moderate), and brain (very low), while no expression could be detected in the other investigated tissues.
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Affiliation(s)
- F M Vaz
- Department of Clinical Chemistry and Pediatrics, Academic Medical Center, University of Amsterdam, The Netherlands
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32
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Kinoshita N, Ghaedi K, Shimozawa N, Wanders RJ, Matsuzono Y, Imanaka T, Okumoto K, Suzuki Y, Kondo N, Fujiki Y. Newly identified Chinese hamster ovary cell mutants are defective in biogenesis of peroxisomal membrane vesicles (Peroxisomal ghosts), representing a novel complementation group in mammals. J Biol Chem 1998; 273:24122-30. [PMID: 9727033 DOI: 10.1074/jbc.273.37.24122] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We isolated peroxisome biogenesis-defective mutants from Chinese hamster ovary cells by the 9-(1'-pyrene)nonanol/ultraviolet (P9OH/UV) method. Seven cell mutants, ZP116, ZP119, ZP160, ZP161, ZP162, ZP164, and ZP165, of 11 P9OH/UV-resistant cell clones showed cytosolic localization of catalase, a peroxisomal matrix enzyme, apparently indicating a defect of peroxisome biogenesis. By transfection of PEX cDNAs and cell fusion analysis, mutants ZP119 and ZP165 were found to belong to a novel complementation group (CG), distinct from earlier mutants. CG analysis by cell fusion with fibroblasts from patients with peroxisome biogenesis disorders such as Zellweger syndrome indicated that ZP119 and ZP165 were in the same CG as the most recently identified human CG-J. The peroxisomal matrix proteins examined, including PTS1 proteins as well as a PTS2 protein, 3-ketoacyl-CoA thiolase, were also found in the cytosol in ZP119 and ZP165. Furthermore, these mutants showed typical peroxisome assembly-defective phenotype such as severe loss of resistance to 12-(1'-pyrene)dodecanoic acid/UV treatment. Most strikingly, peroxisomal reminiscent vesicular structures, so-called peroxisomal ghosts noted in all CGs of earlier Chinese hamster ovary cell mutants as well as in eight CGs of patients' fibroblasts, were not discernible in ZP119 and ZP165, despite normal synthesis of peroxisomal membrane proteins. Accordingly, ZP119 and ZP165 are the first cell mutants defective in import of both soluble and membrane proteins, representing the 14th peroxisome-deficient CG in mammals, including humans.
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Affiliation(s)
- N Kinoshita
- Department of Biology, Kyushu University Faculty of Science, Fukuoka 812-8581, Japan
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33
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Pignocchi C, Berardi E, Cox BS. Nitrate reduction and the isolation of Nit- mutants in Hansenula polymorpha. MICROBIOLOGY (READING, ENGLAND) 1998; 144 ( Pt 8):2323-2330. [PMID: 9720055 DOI: 10.1099/00221287-144-8-2323] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Hansenula polymorpha (syn. Pichia angusta) is able to grow on nitrate as sole nitrogen source. Nitrate reductase (NR) assays, optimized in crude extracts from nitrate-grown cells, revealed that NR preferentially used NADPH, but also used NADH, as electron donor and required FAD for maximum activity. NR activity was present in nitrate-grown and nitrite-grown cells, and was absent in cells grown in ammonium, glutamate and methylamine. Addition of reduced nitrogen compounds to nitrate-grown cells led to loss of NR activity, even if added with nitrate. Under nitrogen starvation, NR activity was not observed; however, following growth on nitrate, NR activity is maintained in the absence of nitrate. Increases but not decreases in NR activity were dependent on protein synthesis. Conditions for chlorate selection were optimized, and Nit- (nitrate-) mutants were isolated. Some of these mutants showed reduced or absent NR activity. Sixty-one NR- mutants revealed the monogenic recessive nature of their lesions and were grouped in 10 complementation classes. These mutants will be used in gene cloning experiments aimed at identifying structural and regulatory elements involved in the first step of nitrate reduction.
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Affiliation(s)
- Cristina Pignocchi
- Laboratorio di Genetica Microbica, Dipartimento di Biotecnologie Agrarie ed Ambientali, Universit degli Studi di AnconaVia Brecce Bianche, 1-60131 AnconaItaly
| | - Enrico Berardi
- Laboratorio di Genetica Microbica, Dipartimento di Biotecnologie Agrarie ed Ambientali, Universit degli Studi di AnconaVia Brecce Bianche, 1-60131 AnconaItaly
| | - Brian S Cox
- Laboratorio di Genetica Microbica, Dipartimento di Biotecnologie Agrarie ed Ambientali, Universit degli Studi di AnconaVia Brecce Bianche, 1-60131 AnconaItaly
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34
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Lorenz P, Maier AG, Baumgart E, Erdmann R, Clayton C. Elongation and clustering of glycosomes in Trypanosoma brucei overexpressing the glycosomal Pex11p. EMBO J 1998; 17:3542-55. [PMID: 9649425 PMCID: PMC1170691 DOI: 10.1093/emboj/17.13.3542] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Kinetoplastid protozoa confine large parts of glycolysis within glycosomes, which are microbodies related to peroxisomes. We cloned the gene encoding the second most abundant integral membrane protein of Trypanosoma brucei glycosomes. The 24 kDa protein is very basic and hydrophobic, with two predicted transmembrane domains. It is targeted to peroxisomes when expressed in mammalian cells and yeast. The protein is a functional homologue of Pex11p from Saccharomyces cerevisiae: pex11Delta mutants, which are defective in peroxisome proliferation, can be complemented by the trypanosome gene. Sequence conservation is significant in the N- and C-terminal domains of all putative Pex11p homologues known, from trypanosomes, yeasts and mammals. Several lines of evidence indicate that these domains are oriented towards the cytosol. TbPex11p can form homodimers, like its yeast counterpart. The TbPEX11 gene is essential in trypanosomes. Inducible overexpression of the protein in T.brucei bloodstream forms causes growth arrest, the globular glycosomes being transformed to clusters of long tubules filling significant proportions of the cytoplasm. Reduced expression results in trypanosomes with fewer, but larger, organelles.
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Affiliation(s)
- P Lorenz
- Zentrum für Molekulare Biologie, Universität Heidelberg, Im Neuenheimer Feld 282
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35
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Parpinello G, Berardi E, Strabbioli R. A regulatory mutant of Hansenula polymorpha exhibiting methanol utilization metabolism and peroxisome proliferation in glucose. J Bacteriol 1998; 180:2958-67. [PMID: 9603888 PMCID: PMC107265 DOI: 10.1128/jb.180.11.2958-2967.1998] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Mutant LGM-128 of Hansenula polymorpha harbors the recessive mutation glr2-1 which confers a complex pleiotropic phenotype, the major feature of which is the metabolically unnecessary induction of methanol utilization metabolism (C1 metabolism) during growth on glucose, whether or not methanol is in the medium. Therefore, in this mutant, peroxisomes are formed and proliferate upon cultivation in glucose-containing media. In these media, LGM-128 shows induction levels of C1 metabolism that are similar to those observed in methanol-containing media. This indicates that GLR2 controls the repression-derepression process stimulated by glucose and that the induction process triggered by methanol plays only a minor role in activating C1 metabolism. Cultivating LGM-128 in methanol and then transferring it to glucose media revealed that active degradative processes occur, leading to the disappearance of C1 metabolism. This observation suggests that, although stimulated by glucose, the two processes are controlled by elements which are, at least in part, distinct. Finally, glr2-1 does not affect ethanol repression, suggesting that in H. polymorpha the two repressing circuits are separated.
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Affiliation(s)
- G Parpinello
- Laboratorio di Genetica Microbica, Dipartimento di Biotecnologie, Università degli Studi di Ancona, Ancona, Italy
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36
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Menéndez J, Delgado J, Gancedo C. Isolation of the Pichia pastoris PYC1 gene encoding pyruvate carboxylase and identification of a suppressor of the pyc phenotype. Yeast 1998; 14:647-54. [PMID: 9639311 DOI: 10.1002/(sici)1097-0061(199805)14:7<647::aid-yea269>3.0.co;2-l] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We have cloned and characterized a gene encoding pyruvate carboxylase from the methylotrophic yeast Pichia pastoris. Disruption of this gene produced inability to grow in minimal medium with glucose as carbon source and ammonium as nitrogen source. Growth was possible with aspartate or glutamate as nitrogen source. The gene PpPYC1 expressed from its own promoter was able to rescue the phenotype of Saccharomyces cerevisiae mutants devoid of pyruvate carboxylase. In a P. pastoris strain carrying a disrupted PpPYC1 gene we have isolated spontaneous mutants able to grow in non-permissive conditions. In a mutant strain grown in glucose several enzymes sensitive to catabolite repression were derepressed. The strain also had elevated levels of glutamate dehydrogenase (NAD) both in repressed and derepressed conditions.
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Affiliation(s)
- J Menéndez
- Centro de Ingeniería Genética y Biotecnología, Havana, Cuba
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37
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Abstract
A major current issue in studies of peroxisome biogenesis is how proteins are imported into the organelle or inserted into its membrane. Recent studies indicate that these two processes use independent pathways. Both appear to have unexpected properties. Matrix proteins can be imported in an oligomeric form which might be facilitated by cycling receptors, whereas insertion of at least some peroxisomal membrane proteins seems to involve the endoplasmic reticulum.
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Affiliation(s)
- W H Kunau
- Abteilung für Zellbiochemie, Medizinische Fakultät der Ruhr-Universität Bochum, 44780 Bochum, Germany.
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38
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Jansen GA, Mihalik SJ, Watkins PA, Jakobs C, Moser HW, Wanders RJ. Characterization of phytanoyl-Coenzyme A hydroxylase in human liver and activity measurements in patients with peroxisomal disorders. Clin Chim Acta 1998; 271:203-11. [PMID: 9565335 DOI: 10.1016/s0009-8981(97)00259-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Phytanoyl-Coenzyme A hydroxylase is a newly recognized peroxisomal enzyme which catalyses the first step in the alpha-oxidation of phytanoyl-Coenzyme A. Since measurement of this enzyme activity in human liver homogenate is of great importance especially in relation to inherited diseases in which this enzyme activity is deficient, we have studied its characteristics in human liver. The results described in this paper show that optimal activity measurements require preformed phytanoyl-Coenzyme A plus 2-oxoglutarate, Fe2+ and ascorbate. The conditions developed can be used to determine phytanoyl-Coenzyme A hydroxylase activity in human liver homogenates which is of utmost importance not only for the diagnosis of patients, but also for the purification of the enzyme from various sources.
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Affiliation(s)
- G A Jansen
- Academic Medical Center, University of Amsterdam, Department of Clinical Biochemistry, The Netherlands
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Waterham HR, Russell KA, Vries Y, Cregg JM. Peroxisomal targeting, import, and assembly of alcohol oxidase in Pichia pastoris. J Biophys Biochem Cytol 1997; 139:1419-31. [PMID: 9396748 PMCID: PMC2132610 DOI: 10.1083/jcb.139.6.1419] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Alcohol oxidase (AOX), the first enzyme in the yeast methanol utilization pathway is a homooctameric peroxisomal matrix protein. In peroxisome biogenesis-defective (pex) mutants of the yeast Pichia pastoris, AOX fails to assemble into active octamers and instead forms inactive cytoplasmic aggregates. The apparent inability of AOX to assemble in the cytoplasm contrasts with other peroxisomal proteins that are able to oligomerize before import. To further investigate the import of AOX, we first identified its peroxisomal targeting signal (PTS). We found that sequences essential for targeting AOX are primarily located within the four COOH-terminal amino acids of the protein leucine-alanine-arginine-phenylalanine COOH (LARF). To examine whether AOX can oligomerize before import, we coexpressed AOX without its PTS along with wild-type AOX and determined whether the mutant AOX could be coimported into peroxisomes. To identify the mutant form of AOX, the COOH-terminal LARF sequence of the protein was replaced with a hemagglutinin epitope tag (AOX-HA). Coexpression of AOX-HA with wild-type AOX (AOX-WT) did not result in an increase in the proportion of AOX-HA present in octameric active AOX, suggesting that newly synthesized AOX-HA cannot oligomerize with AOX-WT in the cytoplasm. Thus, AOX cannot initiate oligomerization in the cytoplasm, but must first be targeted to the organelle before assembly begins.
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Affiliation(s)
- H R Waterham
- Department of Biochemistry and Molecular Biology, Oregon Graduate Institute of Science and Technology, Portland, Oregon 97291-1000, USA
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Jansen GA, Ofman R, Ferdinandusse S, Ijlst L, Muijsers AO, Skjeldal OH, Stokke O, Jakobs C, Besley GT, Wraith JE, Wanders RJ. Refsum disease is caused by mutations in the phytanoyl-CoA hydroxylase gene. Nat Genet 1997; 17:190-3. [PMID: 9326940 DOI: 10.1038/ng1097-190] [Citation(s) in RCA: 223] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Refsum disease is an autosomal-recessively inherited disorder characterized clinically by a tetrad of abnormalities: retinitis pigmentosa, peripheral neuropathy, cerebellar ataxia and elevated protein levels in the cerebrospinal fluid (CSF) without an increase in the number of cells in the CSF. All patients exhibit accumulation of an unusual branched-chain fatty acid, phytanic acid (3,7,11,15-tetramethylhexadecanoic acid), in blood and tissues. Biochemically, the disease is caused by the deficiency of phytanoyl-CoA hydroxylase (PhyH), a peroxisomal protein catalyzing the first step in the alpha-oxidation of phytanic acid. We have purified PhyH from rat-liver peroxisomes and determined the N-terminal amino-acid sequence, as well as an additional internal amino-acid sequence obtained after Lys-C digestion of the purified protein. A search of the EST database with these partial amino-acid sequences led to the identification of the full-length human cDNA sequence encoding PhyH: the open reading frame encodes a 41.2-kD protein of 338 amino acids, which contains a cleavable peroxisomal targeting signal type 2 (PTS2). Sequence analysis of PHYH fibroblast cDNA from five patients with Refsum disease revealed distinct mutations, including a one-nucleotide deletion, a 111-nucleotide deletion and a point mutation. This analysis confirms our finding that Refsum disease is caused by a deficiency of PhyH.
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Affiliation(s)
- G A Jansen
- Department of Clinical Biochemistry, University of Amsterdam, The Netherlands
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41
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Abstract
Recent years have seen remarkable progress in our understanding of the function of peroxisomes in higher and lower eukaryotes. Combined genetic and biochemical approaches have led to the identification of many genes required for the biogenesis of this organelle. This review summarizes recent, rather surprising, results and discusses how they can be incorporated into the current view of peroxisome biogenesis.
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Waterham HR, Digan ME, Koutz PJ, Lair SV, Cregg JM. Isolation of the Pichia pastoris glyceraldehyde-3-phosphate dehydrogenase gene and regulation and use of its promoter. Gene X 1997; 186:37-44. [PMID: 9047342 DOI: 10.1016/s0378-1119(96)00675-0] [Citation(s) in RCA: 321] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We report the cloning and sequence of the glyceraldehyde-3-phosphate dehydrogenase gene (GAP) from the yeast Pichia pastoris. The gene is predicted to encode a 35.4-kDa protein with significant sequence similarity to glyceraldehyde-3-phosphate dehydrogenases from other organisms. Promoter studies in P. pastoris using bacterial beta-lactamase as a reporter showed that the GAP promoter (P(GAP)) is constitutively expressed, although its strength varies depending on the carbon source used for cell growth. Expression of beta-lactamase under control of P(GAP) in glucose-grown cells was significantly higher than under control of the commonly employed alcohol oxidase 1 promoter (P(AOX1)) in methanol-grown cells. As an example of the use of P(GAP), we showed that beta-lactamase synthesized under transcriptional control of P(GAP) is correctly targeted to peroxisomes by addition of either a carboxy-terminal or an amino-terminal peroxisomal targeting signal. P(GAP) has been successfully utilized for synthesis of heterologous proteins from bacterial, yeast, insect and mammalian origins, and therefore is an attractive alternative to P(AOX1) in P. pastoris.
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Affiliation(s)
- H R Waterham
- Department of Chemistry, Biochemistry, and Molecular Biology, Oregon Graduate Institute of Science and Technology, Portland 97291-1000, USA
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