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  • 1
    Electronic Resource
    Electronic Resource
    Microbodies in methanol-assimilating yeasts (1975)
    Springer
    Archives of microbiology 102 (1975), S. 41-44 
    Details
    ISSN: 1432-072X
    Keywords: Yeasts ; Methanol ; Microbodies
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cells of 3 yeast species capable of assimilating methanol have been examined by electron microscopy. When grown on methanol as the sole source of carbon and energy they contained many microbodies. Cells grown on glucose or ethanol either did not contain such bodies at all, or only to a limited extent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00428343
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  • 2
    Electronic Resource
    Electronic Resource
    Cytochemical localization of catalase activity in methanol-grown Hansenula polymorpha (1975)
    Springer
    Archives of microbiology 105 (1975), S. 261-267 
    Details
    ISSN: 1432-072X
    Keywords: Methanol ; Yeasts ; Microbodies ; Diaminobenzidine ; Catalase ; Methanol oxidase ; Hanseula polymorpha
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The localization of peroxidase activity in methanol-grown cells of the yeast Hansenula polymorpha has been studied by a method based on cytochemical staining with diaminobenzidine (DAB). The oxidation product of DAB occurred in microbodies, which characteristically develop during growth on methanol, and in the intracristate space of the mitochondria. The staining of microbodies was H2O2 dependent, appeared to be optimal at pH 10.5, diminished below pH 10 and was inhibited by 20 mM 3-amino 1,2,4 triazole (AT). In contrast to these observations, the reaction in the mitochondria was not H2O2 dependent and not notably affected by differences in pH in the range of 8.5 to 10.5. Microbodies and mitochondria were also stained when H2O2 was replaced by methanol. Appropriate control experiments indicated that in this case methanol oxidase generated the H2O2 for the peroxidative conversion of DAB by catalase. These results suggest that catalase is located in the microbodies of methanol-grown yeasts. A model for a possible physiological function of the microbodies during growth on methanol is put forward.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00447145
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  • 3
    Electronic Resource
    Electronic Resource
    Physiological role of microbodies in the yeast Trichosporon cutaneum during growth on ethylamine as the source of energy, carbon and nitrogen (1986)
    Springer
    Archives of microbiology 145 (1986), S. 39-50 
    Details
    ISSN: 1432-072X
    Keywords: Amine metabolism ; Microbodies ; Amine oxidase ; Cytochemistry ; Cell fractionation ; Trichosporon cutaneum
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Compartmentation of the metabolism of ethylamine in Trichosporon cutaneum X4 was studied in cells, grown on this compound as the sole source of energy, carbon, and nitrogen. Transfer experiments indicated that an amine oxidase is involved in the early metabolism of ethylamine. The synthesis of this enzyme was induced by primary amines and was subject to partial carbon catabolite repression. Repression by ammonium ions was not observed. Adaptation of glucose-grown cells to growth on ethylamine was associated with the development of many microbodies, which developed from already existing organelles present in the inoculum cells and multiplied by division. Cytochemical experiments indicated that the organelles contained amine oxidase and catalase. Therefore, they were considered to play a key role in the metabolism of ethylamine. The physiological significance of the microbodies was investigated by fractionation studies of homogenized protoplasts from ethylamine-grown cells by differential- and sucrose-gradient centrifugation of subcellular organelles. Intact microbodies were only obtained when the isolation procedure was performed at pH 5.8 in the absence of Mg2+-ions. Analysis of the different fractions indicated that the key enzymes of the glyoxylate cycle, namely isocitrate lyase and malate synthase, cosedimented together with catalase and amine oxidase. In addition, activities of malate dehydrogenase, glutamate:oxaloacetate aminotransferase (GOT) and (NAD-dependent) glutamate dehydrogenase were detected in these fractions. Electron microscopy revealed that they mainly contained microbodies. Cytochemical experiments indicated that the above enzymes were all present in the same organelle. These findings suggest that microbodies of ethylamine-grown T. cutaneum X4 produce aspartate, so allowing NADH generated in the oxidation of malate by malate dehydrogenase to be quantitatively reoxidized inside the organelles in a series of reactions involving GOT and glutamate dehydrogenase. Aspartase and fumarase were not detected in the microbodies; activities of these two enzymes were present in the cytoplasm.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00413025
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  • 4
    Electronic Resource
    Electronic Resource
    A proton-translocating adenosine triphosphatase is associated with the peroxisomal membrane of yeasts (1987)
    Springer
    Archives of microbiology 147 (1987), S. 42-47 
    Details
    ISSN: 1432-072X
    Keywords: Hansenula polymorpha ; Yeast ; Peroxisomes ; Proton-translocating ATPase ; Cell fractionation ; Fluorescence quenching studies ; Cytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The association of an ATPase with the yeast peroxisomal membrane was established by both biochemical and cytochemical procedures. Peroxisomes were purified from protoplast homogenates of the methanol-grown yeast Hansenula polymorpha by differential and sucrose gradient centrifugation. Biochemical analysis revealed that ATPase activity was associated with the peroxisomal peak fractions which were identified on the basis of alcohol oxidase and catalase activity. The properties of this ATPase closely resembled those of the mitochondrial ATPase of this yeast. The enzyme was Mg2+-dependent, had a pH optimum of approximately 8.5 and was sensitive to N,N′-dicyclohexylcarbodiimide (DCCD), oligomycin and azide, but not to vanadate. A major difference was the apparent K m for ATP which was 4–6 mM for the peroxisomal ATPase compared to 0.6–0.9 mM for the mitochondrial enzyme. Cytochemical experiments indicated that the peroxisomal ATPase was associated with the membranes surrounding these organelles. After incubations with CeCl3 and ATP specific reaction products were localized on the peroxisomal membrane, both when unfixed isolated peroxisomes or formaldehyde-fixed protoplasts were used. This staining was strictly ATP-dependent; in controls performed i) in the absence of substrate, ii) in the presence of glycerol 2-phosphate instead of ATP, or iii) in the presence of DCCD, staining was invariably absent. Similar staining patterns were observed in subcellular fractions and protoplasts of Candida utilis and Trichosporon cutaneum X4, grown in the presence of ethanol/ethylamine or ethylamine, respectively.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00492903
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  • 5
    Electronic Resource
    Electronic Resource
    Biogenesis and turnover of peroxisomes involved in the concurrent oxidation of methanol and methylamine in Hansenula polymorpha (1981)
    Springer
    Archives of microbiology 129 (1981), S. 35-41 
    Details
    ISSN: 1432-072X
    Keywords: Peroxisome ; Methanol ; Methylamine ; Yeast ; Hansenula polymorpha ; Alcohol oxidase ; Amino oxidase ; Catalase ; Catabolite inactivation ; Turnover ; Cytochemical localization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Growth of Hansenula polymorpha in shake flasks and chemostat cultures in the presence of methanol as the sole source of carbon and methylamine as the sole source of nitrogen was associated with the development of peroxisomes in the cells. The organelles were involved in the concurrent oxidation of these two compounds, since they contained both alcohol oxidase and amine oxidase, which are key enzymes in methanol and methylamine metabolism, respectively. In addition catalase was present. Peroxisomes with a completely crystalline substructure were observed in methanol-limited chemostat-grown cells. Amine oxidase probably formed an integral part of these crystalloids, whereas catalase was present in a freely diffusable form. Transfer of cells, grown in a methanol-limited chemostat in the presence of methylamine into glucose/ammonium sulphate media resulted in the loss of both alcohol oxidase and amine oxidase activity from the cells. This process was associated with degradation of the crystalline peroxisomes. However, when cells were transferred into glucose/methylamine media, amine oxidase activity only declined during 2 h after the transfer and thereafter increased again. This subsequent rise in amine oxidase activity was associated with the development of new peroxisomes in the cells in which degradation of the crystalline peroxisomes, originally present, continued. These newly formed organelles probably originated from peroxisomes which had not been affected by degradation. When in the methanollimited chemostat methylamine was replaced by ammonium sulphate, repression of the synthesis of amine oxidase was observed. However, inactivation of this enzyme or degradation of peroxisomes was not detected. The decrease of amine oxidase activity in the culture was accounted for by dilution of enzyme as a result of growth and washout.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00417176
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  • 6
    Electronic Resource
    Electronic Resource
    Characterization of glyoxysomes in yeasts and their transformation into peroxisomes in response to changes in environmental conditions (1983)
    Springer
    Archives of microbiology 136 (1983), S. 28-38 
    Details
    ISSN: 1432-072X
    Keywords: Yeasts ; Candida utilis ; Hansenula polymorpha ; Microbodies ; Peroxisomes ; Glyoxysomes ; Cell fractionation ; Cytochemistry ; Catalase ; Glyoxylate cycle ; Oxidase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract During growth of the yeasts Candida utilis and Hansenula polymorpha in mineral media containing ethanol as a carbon source and ammonium sulphate as a nitrogen source, the specific activities of isocitrate lyase and malate synthase were significantly increased when compared to glucose/ammonium sulphate-grown cells. In addition to the enhanced levels of these glyoxylate cycle enzymes, an increase in the specific activities of d-amino acid oxidase, amine oxidase or urate oxidase was observed when ammonium sulphate in the ethanol medium was replaced by d-alanine, methyl- or ethylamine, or uric acid. The subcellular localization of these enzymes was investigated by cell fractionation studies involving homogenization of protoplasts followed by differential and sucrose gradient centrifugation. In ethanol/ammonium sulphate-grown cells, isocitrate lyase and malate synthase cosedimented in a fraction together with catalase and part of the malate dehydrogenase. Electron microscopy revealed that this fraction consisted of microbodies which must be regarded as glyoxysomes. Two other glyoxylate cycle enzymes, citrate synthase and aconitase together with the other part of malate dehydrogenase, cosedimented with cytochrome c oxidase, a mitochondrial marker enzyme. In ethanol/d-alanine-, ethanol/methylamine- or ethanol/ethylamine-grown C. utilis and ethanol/uric acid-grown H. polymorpha, a peroxisomal enzyme, i.e. d-amino acid oxidase, amine oxidase or uric acid oxidase cosedimented with the glyoxysomal key enzymes. Cytochemical staining experiments demonstrated that in these variously-grown cells the activities of the oxidases were confined to the microbodymatrix; this also contained malate synthase activity. Transfer of C. utilis cells from glucose/ammonium sulphate- into ethanol/ammonium sulphate-containing media resulted in an increase in the original size and volume fraction of the microbodies. A further increase was observed when ammonium sulphate was replaced by methylamine. Essentially similar results were obtained with H. polymorpha cells. In neither of the two organisms indications of de novo synthesis of microbodies was obtained during transfer experiments. Invariably the microbodies developing in cells placed in the new environment originated from organelles already present in the inoculum cells by import of the substratespecific enzyme protein(s). The combined results of biochemical, cytochemical and electron microscopical experiments showed that in the yeasts studied under appropriate conditions glyoxysomal and peroxisomal enzyme activities were localized in one and the same microbody, rather than in separate organelles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00415606
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  • 7
    Electronic Resource
    Electronic Resource
    Characterization of peroxisomes in glucose-grown Hansenula polymorpha and their development after the transfer of cells into methanol-containing media (1979)
    Springer
    Archives of microbiology 120 (1979), S. 167-175 
    Details
    ISSN: 1432-072X
    Keywords: Peroxisome ; Biogenesis ; Yeast ; Hansenula polymorpha ; Cytochemical staining ; Methanol
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Cells of Hansenula polymorpha growing exponentially on glucose generally contained a single peroxisome of small dimension, irregular in shape and located in close proximity to the cell wall. Crystalline inclusions in the peroxisomal matrix were not observed. Associations of the organelles with one or more strands of endoplasmic reticulum were evident. In stationary phase cells the size of the peroxisomes had increased considerably. They were more cubical in form and showed a partly or completely crystalline matrix. After the transfer of cells growing exponentially on glucose into media containing methanol, large peroxisomes with a partly crystalline matrix developed in the cells within 6 h. These organelles originated from the small peroxisomes in the glucose-grown cells. De novo synthesis of peroxisomes was not observed. Prolonged cultivation in the presence of methanol resulted in a gradual increase in the number of peroxisomes by means of separation of small peroxisomes from mature organelles. During growth of peroxisomes associations with the endoplasmic reticulum remained evident. The increase in volume density of peroxisomes in stationary phase cells grown on glucose and in methanol-grown cells was accompanied by the synthesis of the peroxisomal enzymes alcohol oxidase and catalase. Cytochemical staining techniques revealed that alcohol oxidase activity was only detected when the peroxisomes contained a crystalloid inclusion. Since in peroxisomes of an alcohol oxidase-negative mutant of Hansenula polymorpha crystalline inclusions were never detected, it is concluded that the development of crystalloids inside peroxisomes is due to the accumulation of alcohol oxidase in these organelles.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00409104
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  • 8
    Electronic Resource
    Electronic Resource
    Development of crystalline peroxisomes in methanol-grown cells of the yeast Hansenula polymorpha and its relation to environmental conditions (1978)
    Springer
    Archives of microbiology 117 (1978), S. 153-163 
    Details
    ISSN: 1432-072X
    Keywords: Peroxisome ; Methanol ; Cytochemical staining ; Yeast ; Hansenula polymorpha
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The development of peroxisomes has been studied in cells of the yeast Hansenula polymorpha during growth on methanol in batch and chemostat cultures. During bud formation, new peroxisomes were generated by the separation of small peroxisomes from mature organelles in the mother cells. The number of peroxisomes migrating to the buds was dependent upon environmental conditions. Aging of cells was accompanied by an increase in size of the peroxisomes and a subsequent increase in their numbers per cell. Their ultimate shape and substructure as well as their number per cell was dependent upon the physiological state of the culture. The change in number and volume density of peroxisomes was related to the level of alcohol oxidase in the cells. Development of peroxisomes in cells of batch cultures was accompanied by an increase in size of the crystalline inclusions in the organelles; they had become completely crystalline when the cells were in the stationary phase. Peroxisomes in cells from methanol-limited chemostat cultures were completely crystalline, irrespective of growth rate. Results of biochemical and cytochemical experiments suggested that alcohol oxidase is a major component of the crystalline inclusions in the peroxisomes of methanol-grown Hansenula polymorpha. Possible mechanisms involved in the ultrastructural changes in peroxisomes during their development have been discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00402303
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  • 9
    Electronic Resource
    Electronic Resource
    Peroxisomes in intestinal and gallbladder epithelial cells of the stickleback, Gasterosteus aculeatus L. (Teleostei) (1988)
    Springer
    Cell & tissue research 251 (1988), S. 685-689 
    Details
    ISSN: 1432-0878
    Keywords: Peroxisomes ; D-amino acid oxidase ; Catalase ; Cytochemistry ; Intestinal epithelium ; Gallbladder epithelium ; Gasterosteus aculeatus (Teleostei)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary The occurrence of microbodies in the epithelial cells of the intestine and gallbladder of the stickleback, Gasterosteus aculeatus L., is described. In the intestine the organelles are predominantly located in the apical and perinuclear zone of the cells and may contain small crystalline cores. In gallbladder epithelial cells the microbodies are distributed randomly. The latter organelles are characterized by the presence of large crystalloids. Cytochemical and biochemical experiments show that catalase and D-amino acid oxidase are main matrix components of the microbodies in both the intestinal and gallbladder epithelia. These organelles therefore are considered peroxisomes. In addition, in intestinal mucosa but not in gallbladder epithelium a low activity of palmitoyl CoA oxidase was detected biochemically. Urate oxidase and L-α hydroxy acid oxidase activities could not be demonstrated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00214018
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