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Progress in Histochemistry and... 1989(1) alpha-HAOX has a broad substrate specificity. In rat kidney, the enzyme reacts with aliphatic and aromatic alpha-hydroxy acids, in rat liver, however, only with... (Review)
Review
(1) alpha-HAOX has a broad substrate specificity. In rat kidney, the enzyme reacts with aliphatic and aromatic alpha-hydroxy acids, in rat liver, however, only with aliphatic ones. (2) The best substrate for the demonstration of alpha-HAOX activity in rat and human liver is glycolate. (3) alpha-hydroxy butyric acid is the best substrate in the luminometric assay for the demonstration of alpha-HAOX activity in the rat kidney, whereas glycolate is not catalysed by the enzyme. (4) In the proximal tubulus epithelial cells of the rat kidney alpha-HAOX is concentrated in the peripheral matrix of the peroxisomes.
Topics: Alcohol Oxidoreductases; Animals; D-Amino-Acid Oxidase; Histocytochemistry; Humans; Lipid Metabolism; Microbodies; Microscopy, Electron; Oxidoreductases; Urate Oxidase; Xanthine Oxidase
PubMed: 2574900
DOI: 10.1016/s0079-6336(89)80008-7 -
Developmental Neuroscience 1987The peroxisome is a subcellular organelle with important functions in plants and protozoa, which during the last decade has also been shown to have a role in mammalian... (Review)
Review
The peroxisome is a subcellular organelle with important functions in plants and protozoa, which during the last decade has also been shown to have a role in mammalian lipid and amino acid metabolism. These functions include steps in the synthesis of ether lipids and bile acids and fatty acid beta-oxidation, particularly those of very long chain fatty acids. The proposition that the peroxisome carries out significant functions in man is highlighted by the fact that lack of this organelle is associated with severe abnormalities in many human organs. Human peroxisomal disorders are now grouped into three general categories. In the first group, peroxisomes are lacking or reduced in number. This group includes the Zellweger cerebro-hepato-renal syndrome, neonatal adrenoleukodystrophy, infantile Refsum's disease and hyperpipecolic acidemia. These patients lack the capacity to synthesize ether lipids and to oxidize very long chain fatty acids or phytanic acid, and they show abnormally high levels of pipecolic acid and bile acid intermediates. These patients rarely survive early childhood, have severe neurological deficits and multiple malformations. A second group includes the 'pseudo-Zellweger' syndrome and the rhizomelic form of chondrodysplasia punctata. Here the peroxisomal structure is intact, but there is deficient function of several peroxisomal enzymes. The third group includes X-linked adrenoleukodystrophy, acatalasemia and 'adult' Refsum's disease. The peroxisomal structure is intact, and the defect in each instance is thought to involve a mutation which affects a single peroxisomal enzyme. Peroxisomal disorders are of current interest because they occur more commonly than had been recognized and show phenotypic and genotypic heterogeneity. Their study provides the opportunity to learn more about the role of the peroxisome in normal brain function and development.
Topics: Animals; Catalase; Humans; Lipid Metabolism, Inborn Errors; Metabolism, Inborn Errors; Microbodies
PubMed: 3297624
DOI: 10.1159/000111604 -
The EMBO Journal Dec 1985To determine how microbody enzymes enter microbodies, we are studying the genes for cytosolic and glycosomal (microbody) isoenzymes in Trypanosoma brucei. We have found... (Comparative Study)
Comparative Study
To determine how microbody enzymes enter microbodies, we are studying the genes for cytosolic and glycosomal (microbody) isoenzymes in Trypanosoma brucei. We have found three genes (A, B and C) coding for phosphoglycerate kinase (PGK) in a tandem array in T. brucei. Gene B codes for the cytosolic and gene C for the glycosomal isoenzyme. Genes B and C are 95% homologous, and the predicted protein sequences share approximately 45% amino acid homology with other eukaryote PGKs. The microbody isoenzyme differs from the cytosolic form and other PGKs in two respects: a high positive charge and a carboxy-terminal extension of 20 amino acids. Our results show that few alterations are required to redirect a protein from cytosol to microbody. From a comparison of our results with the unpublished data for three other glycosomal glycolytic enzymes we infer that the high positive charge represents the major topogenic signal for uptake of proteins into glycosomes.
Topics: Amino Acid Sequence; Animals; Base Sequence; Cytosol; DNA Restriction Enzymes; Genes; Humans; Isoenzymes; Microbodies; Phosphoglycerate Kinase; Sequence Homology, Nucleic Acid; Species Specificity; Trypanosoma brucei brucei
PubMed: 3004970
DOI: 10.1002/j.1460-2075.1985.tb04152.x -
The Journal of Membrane Biology Jan 1992During the last few years much has been learned regarding signals that target proteins into peroxisomes. The emphasis in the near future will undoubtedly shift towards... (Review)
Review
During the last few years much has been learned regarding signals that target proteins into peroxisomes. The emphasis in the near future will undoubtedly shift towards the elucidation of the mechanism of import. The use of mammalian and yeast cells deficient in peroxisome assembly and/or import (Zoeller & Raetz, 1986; Erdmann et al., 1989; Cregg et al., 1990; Morand et al., 1990; Tsukamoto, Yokota & Fujiki, 1990) should provide a handle on the genes (Erdmann et al., 1991; Tsukamoto et al., 1991) involved in these processes. This will have to be coupled with further development of in vitro systems which will permit the dissection of the steps in the translocation of proteins into peroxisomes. Though some progress has been made in the development of such assays (Imanaka et al., 1987; Small et al., 1987, 1988; Miyazawa et al., 1989), the fragility of peroxisomes and the absence of biochemical hallmarks of import (such as protein modifications or proteolytic processing) have hindered progress. Since peroxisomes exist in the form of a reticulum in mammalian cells (Gorgas, 1984), all peroxisome purification schemes (from mammalian cells at least) must undoubtedly rupture the peroxisomes, which then reseal to form vesicular structures. Additionally, the reliance on the latency of catalase alone as a major criterion for the integrity of peroxisomes ignores the fact that many other matrix proteins leak out of peroxisomes at vastly different rates during purification of the organelles (Thompson & Krisans, 1990). In view of these problems, the development of peroxisomal transport assays with semi-intact cells would also constitute an important advance.(ABSTRACT TRUNCATED AT 250 WORDS)
Topics: Amino Acid Sequence; Animals; Humans; Membrane Proteins; Microbodies; Mitochondria; Molecular Sequence Data; Oligopeptides; Protein Sorting Signals; Proteins
PubMed: 1552566
DOI: 10.1007/BF00233350 -
The Journal of Cell Biology Sep 1991Peroxisomes, glyoxysomes, glycosomes, and hydrogenosomes have each been classified as microbodies, i.e., subcellular organelles with an electron-dense matrix that is... (Comparative Study)
Comparative Study
Peroxisomes, glyoxysomes, glycosomes, and hydrogenosomes have each been classified as microbodies, i.e., subcellular organelles with an electron-dense matrix that is bound by a single membrane. We investigated whether these organelles might share a common evolutionary origin by asking if targeting signals used for translocation of proteins into these microbodies are related. A peroxisomal targeting signal (PTS) consisting of the COOH-terminal tripeptide serine-lysine-leucine-COOH has been identified in a number of peroxisomal proteins (Gould, S.J., G.-A. Keller, N. Hosken, J. Wilkinson, and S. Subramani. 1989. J. Cell Biol. 108:1657-1664). Antibodies raised to a peptide ending in this sequence (SKL-COOH) recognize a number of peroxisomal proteins. Immunocryoelectron microscopy experiments using this anti-SKL antibody revealed the presence of proteins containing the PTS within glyoxysomes of cells from Pichia pastoris, germinating castor bean seeds, and Neurospora crassa, as well as within the glycosomes of Trypanosoma brucei. Western blot analysis of purified organelle fractions revealed the presence of many proteins containing this PTS in both glyoxysomes and glycosomes. These results indicate that at least one of the signals, and therefore the mechanism, for protein translocation into peroxisomes, glyoxysomes, and glycosomes has been conserved, lending support to a common evolutionary origin for these microbodies. Hydrogenosomes, the fourth type of microbody, did not contain proteins that cross-reacted with the anti-PTS antibody, suggesting that this organelle is unrelated to microbodies.
Topics: Amino Acid Sequence; Animals; Biological Evolution; Biological Transport; Blotting, Western; Cell Compartmentation; Microbodies; Microscopy, Electron; Molecular Sequence Data; Molecular Weight; Neurospora crassa; Organelles; Peptides; Plants, Toxic; Proteins; Ricinus; Trypanosoma brucei brucei; Yeasts
PubMed: 1831458
DOI: 10.1083/jcb.114.5.893 -
Gene Jun 1990In the primitive eukaryotic parasite, Trypanosoma brucei, most of the enzymes of glycolysis are located within microbody organelles called glycosomes. Proteins destined...
In the primitive eukaryotic parasite, Trypanosoma brucei, most of the enzymes of glycolysis are located within microbody organelles called glycosomes. Proteins destined for the glycosome are synthesized on free ribosomes and post-translationally translocated into the organelle. The gene, gPGK, encoding the glycosomal isozyme of phosphoglycerate kinase (gPGK), was cloned adjacent to a T7 promoter and cotransformed with a plasmid encoding T7 RNA polymerase into Escherichia coli Pgk-cells. Functional complementation occurred, but only after the creation of a ribosome-binding site by mutagenesis. This represents the first example of complementation of an E. coli mutant with a gene encoding a microbody protein. Enzymatically active recombinant gPGK was purified to near homogeneity by ion exchange chromatography from highly expressing E. coli. The recombinant protein will aid in studies of glycosomal biogenesis.
Topics: Animals; Base Sequence; Codon; Escherichia coli; Genetic Complementation Test; Isoenzymes; Microbodies; Molecular Sequence Data; Mutation; Phosphoglycerate Kinase; Recombination, Genetic; Trypanosoma brucei brucei
PubMed: 2205531
DOI: 10.1016/0378-1119(90)90182-q -
Cell Biochemistry and Function Sep 1992
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Molecular Microbiology Aug 2004Peroxisomes are membrane-bounded organelles that compartmentalize a variety of metabolic functions. Perhaps the most divergent peroxisomes known are the glycosomes of... (Review)
Review
Peroxisomes are membrane-bounded organelles that compartmentalize a variety of metabolic functions. Perhaps the most divergent peroxisomes known are the glycosomes of trypanosomes and their relatives. The glycolytic pathway of these organisms resides within the glycosome. The development of robust molecular genetic and proteomic approaches coupled with the completion of the genome sequence of the pathogens Trypanosoma brucei, Trypanosoma cruzi, and Leishmania major provides an opportunity to determine the complement of proteins within the glycosome and the function of compartmentation. Studies now suggest that regulation of glycolysis is a strong driving force for maintenance of the glycosome.
Topics: Animals; Glycolysis; Leishmania; Microbodies; Peroxisomes; Trypanosoma
PubMed: 15255886
DOI: 10.1111/j.1365-2958.2004.04203.x -
Annual Review of Cell Biology 1993
Review
Topics: Animals; CHO Cells; Cricetinae; Extracellular Matrix Proteins; Humans; In Vitro Techniques; Membrane Proteins; Microbodies; Mutation; Saccharomyces cerevisiae; Signal Transduction
PubMed: 8280468
DOI: 10.1146/annurev.cb.09.110193.002305 -
European Journal of Biochemistry Nov 1975Profuse appearance of microbodies was observed in the cells of methanol-utilizing yeasts in connection with the enhanced catalase activity. These microbodies were...
Profuse appearance of microbodies was observed in the cells of methanol-utilizing yeasts in connection with the enhanced catalase activity. These microbodies were isolated successfully by means of sucrose gradient centrifugation from the methanol-grown cells of Kloeckera sp. no. 2201. Localization of a flavin-dependent alcohol oxidase as well as characteristic microbody enzymes (catalase and D-amino acid oxidase) were ascertained in the isolated microbodies, whereas formaldehyde and formate dehydrogenases were detected in the cytoplasmic region. Localization of catalase in the isolated microbody was also demonstrated by the cytochemical technique with 3,3'-diaminobenzidine.
Topics: Alcohol Oxidoreductases; Catalase; Cytoplasm; Electron Transport Complex IV; Methanol; Microbodies; Microscopy, Electron; Mitosporic Fungi; Organoids
PubMed: 173538
DOI: 10.1111/j.1432-1033.1975.tb02482.x