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Biochemical Society Transactions Feb 1990
Review
Topics: Amino Acid Sequence; Animals; Microbodies; Molecular Sequence Data; Proteins; Rats; Saccharomyces cerevisiae
PubMed: 2185098
DOI: 10.1042/bst0180085 -
Molecular Membrane Biology 2005Peroxisomes, glyoxysomes and glycosomes are related organelles found in different organisms. The morphology and enzymic content of the different members of this... (Review)
Review
Peroxisomes, glyoxysomes and glycosomes are related organelles found in different organisms. The morphology and enzymic content of the different members of this organelle family differ considerably, and may also be highly dependent on the cell's environmental conditions or life cycle. However, all peroxisome-like organelles have in common a number of characteristic enzymes or enzyme systems, notably enzymes dealing with reactive oxygen species. All organelles of the family follow essentially the same route of biogenesis, but with species-specific differences. Sets of proteins called peroxins are involved in different aspects of the formation and proliferation of peroxisomes such as import of proteins in the organellar matrix, insertion of proteins in the membrane, etc. In different eukaryotic lineages these functions are carried out by often--but not always--homologous yet poorly conserved peroxins. The process of biogenesis and the nature of the proteins involved suggest that all members of the peroxisome family evolved from a single organelle in an ancestral eukaryotic cell. This original peroxisome was possibly derived from a cellular membrane system such as the endoplasmic reticulum. Most of the organism-specific functions of the extant organelles have been acquired later in evolution.
Topics: Animals; Evolution, Molecular; Glyoxysomes; Humans; Intracellular Membranes; Microbodies; Peroxisomes; Protein Transport; Proteins
PubMed: 16092531
DOI: 10.1080/09687860400024186 -
Microscopy Research and Technique Mar 1997Peroxisomes, cytoplasmic organelles limited by a single membrane and with a matrix of moderate electron density, are present in a great number of cells, namely in... (Review)
Review
Peroxisomes, cytoplasmic organelles limited by a single membrane and with a matrix of moderate electron density, are present in a great number of cells, namely in adrenal cortex and other steroid-secreting organs. Presently peroxisomes are considered to be involved in important metabolic processes. They intervene in: (1) the production and degradation of H2O2; (2) biosynthesis of ether-phospholipids, cholesterol, dolichol, and bile acids; (3) oxidation of very long chain fatty acids, purines, polyamines, and prostaglandins; (4) catabolism of pipecolic, phythanic and glyoxylic acids; and (5) gluconeogenesis. Recent studies demonstrated that the experimental alterations in the normal steroidogenesis, produce significant morphological and biochemical changes in peroxisomes. Besides this, the presence of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (the key enzyme in the de novo cholesterol synthesis from acetate) and of sterol carrier protein-2 (SCP2), which is involved in the cholesterol metabolism and steroid metabolic pathways, are located in peroxisomes of steroid-secreting cells. In addition, patients with peroxisome diseases present deficiency in steroidogenesis, as well as reduced levels of SCP2. These data pointed out the important role of peroxisomes in steroid biosynthesis.
Topics: Adrenal Cortex Hormones; Animals; Cell Respiration; Fatty Acids; Histocytochemistry; Humans; Microbodies; Peroxisomal Disorders; Steroids; Subcellular Fractions
PubMed: 9142695
DOI: 10.1002/(SICI)1097-0029(19970315)36:6<493::AID-JEMT6>3.0.CO;2-J -
The Journal of Eukaryotic Microbiology Nov 2022Kinetoplastea and Diplonemea possess peroxisome-related organelles that, uniquely, contain most of the enzymes of the glycolytic pathway and are hence called glycosomes.... (Review)
Review
Kinetoplastea and Diplonemea possess peroxisome-related organelles that, uniquely, contain most of the enzymes of the glycolytic pathway and are hence called glycosomes. Enzymes of several other core metabolic pathways have also been located in glycosomes, in addition to some characteristic peroxisomal systems such as pathways of lipid metabolism. A considerable amount of research has been performed on glycosomes of trypanosomes since their discovery four decades ago. Not only the role of the glycosomal enzyme systems in the overall cell metabolism appeared to be unique, but also the organelles display remarkable features regarding their biogenesis and structural properties. These features are similar to those of the well-studied peroxisomes of mammalian and plant cells and yeasts yet exhibit also differences reflecting the large evolutionary distance between these protists and the representatives of other major eukaryotic lineages. Despite all research performed, many questions remain about various properties and the biological roles of glycosomes and peroxisomes. Here, we review the current knowledge about glycosomes, often comparing it with information about peroxisomes. Furthermore, we highlight particularly many questions that remain about the biogenesis, and the heterogeneity in structure and content of these enigmatic organelles, and the properties of their boundary membrane.
Topics: Animals; Microbodies; Peroxisomes; Trypanosoma; Euglenozoa; Homeostasis; Mammals
PubMed: 35175680
DOI: 10.1111/jeu.12897 -
BioEssays : News and Reviews in... Jan 1997Peroxisomes are eukaryotic organelles that are the subcellular location of important metabolic reactions. In humans, defects in the organelle's function are often... (Review)
Review
Peroxisomes are eukaryotic organelles that are the subcellular location of important metabolic reactions. In humans, defects in the organelle's function are often lethal. Yet, relative to other organelles, little is known about how cells maintain and propagate peroxisomes or how they direct specific sets of newly synthesized proteins to these organelles (peroxisome biogenesis/assembly). In recent years, substantial progress has been made in elucidating aspects of peroxisome biogenesis and in identifying PEX genes whose products, peroxins, are essential for one or more of these processes. The most progress has been made in understanding the mechanism by which peroxisome matrix proteins are imported into the organelles. Signal sequences responsible for targeting proteins to the organelle have been defined. Potential signal receptor proteins, a receptor docking protein and other components of the import machinery have been identified, along with insights into how they operate. These studies indicate that multiple peroxisomal protein-import mechanisms exist and that these mechanisms are novel, not simply variations of those described for other organelles.
Topics: Biological Transport, Active; Carrier Proteins; Humans; Membrane Lipids; Membrane Proteins; Microbodies; Models, Biological; Proteins; Receptors, Cell Surface; Yeasts
PubMed: 9008417
DOI: 10.1002/bies.950190110 -
Molecular and Biochemical Parasitology Jun 2001Peroxisomes of higher eukaryotes, glycosomes of kinetoplastids, and glyoxysomes of plants are related microbody organelles that perform differing metabolic functions... (Review)
Review
Peroxisomes of higher eukaryotes, glycosomes of kinetoplastids, and glyoxysomes of plants are related microbody organelles that perform differing metabolic functions tailored to their cellular environments. The close evolutionary relationship of these organelles is most clearly evidenced by the conservation of proteins involved in matrix protein import and biogenesis. The glycosome can be viewed as an offshoot of the peroxisomal lineage with additional metabolic functions, specifically glycolysis and purine salvage. Within the parasitic protozoa, only kinetoplastids have been conclusively demonstrated to possess glycosomes or indeed any peroxisome-like organelle. The importance of glycosomal pathways and their compartmentation emphasizes the potential of the glycosome and glycosomal proteins as drug targets.
Topics: Animals; Leishmania; Microbodies; Peroxisomes; Protozoan Proteins; Trypanosoma
PubMed: 11377736
DOI: 10.1016/s0166-6851(01)00261-4 -
Hoppe-Seyler's Zeitschrift Fur... Feb 19761) Catalase from green leaves of Lens culinaris (lentils) was investigated with respect to isoenzyme patterns. In contrast to other plants, which have been reported to...
1) Catalase from green leaves of Lens culinaris (lentils) was investigated with respect to isoenzyme patterns. In contrast to other plants, which have been reported to contain multiple forms of catalase, only one form of this enzyme was revealed when crude extracts were subjected to starch gel electrophoresis or to polyacrylamide disc-gel electrophoresis. Furthermore, catalases from leaves, stems and cotyledons were electrophoretically identical. 2) The leaf enzyme has been purified by conventional methods to apparent homogeneity. It has a molecular weight of 225 000 (ultracentrifuge) and is composed of four identical subunits of molecular weight 54 000 (sodium dodecylsulphate gel electrophoresis). The ratio A280/A405 of the pure enzyme was found to be 1.5. The isoelectric point is at pH 5.5. The enzyme, very labile at pH-values below 7.0, is stable in Tris chloride and potassium phosphate buffers between pH 7.5 and 9.5. It is slowly inactivated by 1mM dithiothreitol and is rapidly inactivated by 1mM mercaptoethanol. 3) The catalase was shown to be the major protein component of the peroxisomal matrix. It could not be detected at the membranes of the leaf peroxisomes.
Topics: Catalase; Dithiothreitol; Hydrogen-Ion Concentration; Isoelectric Point; Isoenzymes; Microbodies; Molecular Weight; Plants
PubMed: 3464
DOI: 10.1515/bchm2.1976.357.1.163 -
Biology of the Cell 1993Peroxisomes are essential in cellular metabolism as their dysgenesis or defects in single enzymes or impairment of multiple peroxisomal enzymatic functions have been... (Comparative Study)
Comparative Study Review
Peroxisomes are essential in cellular metabolism as their dysgenesis or defects in single enzymes or impairment of multiple peroxisomal enzymatic functions have been found in several inherited metabolic diseases with serious clinical sequelae. The assembly and formation of these cytoplasmic organelles constitute a major and intriguing research topic. In the present study the biogenesis of peroxisomes and the developmental patterns of their enzymes have been reviewed during embryonic and/or post-embryonic ontogenesis of lower (amphibians) and higher (avians, mammals) vertebrates. In developing vertebrates, epithelial cell differentiation is accompanied by increases in frequency and size of peroxisomes. The tissue-specific expression of peroxisomal enzymes contributes substantially to the biochemical maturation of epithelial cells. The relationship between biogenesis of peroxisomes, expression of peroxisomal enzymes and structural and functional cellular phenotype has also been investigated in differentiating epithelial cells along the crypt-villus axis of the adult rat intestine. Cytochemical studies at the ultrastructural level have provided evidence that peroxisomes are already present in proliferating cells of the intestinal crypt region before they begin to differentiate. Migration and differentiation of intestinal epithelial cells from crypt to villus compartments are marked by significant increases in number and size of catalase-positive structures. Increasing activity gradients from crypt to surface areas are found for the peroxisomal oxidases examined (enzymes of the peroxisomal beta-oxidation system, D-amino acid oxidase and polyamine oxidase). Thus, peroxisomes are more and more involved in oxidative metabolic pathways as intestinal epithelial cells differentiate. Finally, we have analyzed the peroxisomal behaviour in human neoplastic epithelial cells. The presence of peroxisomes has been cytochemically revealed in human breast and colon carcinomas. Peroxisomal enzyme specific activities are significantly lower in human breast and colon carcinomas than in the adjacent healthy mucosa. Furthermore, a relationship is found between the specific activities of some peroxisomal enzymes and the histological tumour grades.
Topics: Amphibians; Animals; Cell Differentiation; Humans; Intestines; Metamorphosis, Biological; Microbodies; Neoplasms; Vertebrates
PubMed: 8518747
DOI: 10.1016/s0248-4900(05)80177-7 -
Toxicology and Applied Pharmacology Aug 1978
Topics: Animals; Body Weight; Carnitine Acyltransferases; Carnitine O-Acetyltransferase; Catalase; Liver; Male; Microbodies; Organ Size; Organoids; Plasticizers; Rabbits; Rats; Rats, Inbred F344
PubMed: 705785
DOI: 10.1016/0041-008x(78)90111-4 -
Neurochemical Research Apr 1999Peroxisomes are subcellular organelles catalyzing a number of indispensable functions in cellular metabolism. The importance of peroxisomes in man is stressed by the... (Review)
Review
Peroxisomes are subcellular organelles catalyzing a number of indispensable functions in cellular metabolism. The importance of peroxisomes in man is stressed by the existence of an expanding group of genetic diseases in which there is an impairment in one or more peroxisomal functions. Much has been learned in recent years about these functions and many of the enzymes involved have been characterized, purified and their cDNAs cloned. This has allowed resolution of the enzymatic and molecular basis of many of the single peroxisomal enzyme deficiencies. Similarly, the molecular basis of the peroxisome biogenesis disorders is also being resolved rapidly thanks to the successful use of CHO as well as yeast mutants. In this paper we will provide an overview of the peroxisomal disorders with particular emphasis on their clinical, biochemical and molecular characteristics.
Topics: Animals; Humans; Microbodies; Oxidation-Reduction; Peroxisomal Disorders
PubMed: 10227688
DOI: 10.1023/a:1022592014988