Toxicity of Hyperbaric Oxygen to Yeasts Displaying Periodic Enzyme Synthesis

Gifford, G. D.; Pritchard, G. G.

doi:10.1099/00221287-56-2-143

Cited by 7 publications

(5 citation statements)

References 4 publications

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“…Catalase activity showed relatively little variation through the cell-cycle and it is difficult to distinguish between the possible occurrence of two or three maxima. Similar changes in catalase activity have been observed in glucose-grown S. cerevisiae (Gifford & Pritchard, 1969). The two maxima observed for acid p-nitrophenylphosphatase contrast with the continuous synthesis of this enzyme previously demonstrated in the cell-cycle of S. pombe strain 132 grown under similar conditions (Mitchison & Creanor, 1969).…”

Section: Discussionsupporting

confidence: 78%

Oscillations of enzyme activities during the cell-cycle of a glucose-repressed fission-yeast Schizosaccharomyces pombe 972h

Poole¹,

Lloyd²

1973

Biochemical Journal

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1. Increased specific activities of cytochrome c oxidase, catalase, succinate dehydrogenase, succinate-cytochrome c oxidoreductase, NADH-cytochrome c oxidoreductase and malate dehydrogenase were observed during glucose de-repression of Schizosaccharomyces pombe. 2. The cell-cycle of this organism was analysed by three different methods: (a) harvesting of cells at intervals from a synchronous culture, (b) separation of cells by rate-zonal centrifugation into different size classes and (c) separation of cells by isopycnic-zonal centrifugation into different density classes. 3. Measurement of enzyme activities during the cell-cycle showed that all the enzymes assayed [cytochrome c oxidase, catalase, acid p-nitrophenylphosphatase, NADH-dehydrogenase, NADH-cytochrome c oxidoreductase, NADPH-cytochrome c oxidoreductase, succinate dehydrogenase, malate dehydrogenase, isocitrate dehydrogenase (NADP) and fumarate hydratase] show periodic expression as ;peaks'. 4. Cytochrome c oxidase shows a single maximum at 0.67 of a cycle, whereas succinate dehydrogenase exhibits two maxima separated by 0.5 of a cell-cycle. 5. All other enzymes assayed showed two distinct maxima per cell-cycle; for catalase, malate dehydrogenase and NADPH-cytochrome c oxidoreductase there is the possibility of multiple fluctuations. 6. The single maximum of cytochrome c oxidase appears at a similar time in the cycle to one maximum of each of the other enzymes studied, except for NADH dehydrogenase. 7. These results are discussed with reference to previous observations on the expression of enzyme activities during the cell-cycle of yeasts.

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Section: Discussionsupporting

confidence: 78%

Oscillations of enzyme activities during the cell-cycle of a glucose-repressed fission-yeast Schizosaccharomyces pombe 972h

Poole¹,

Lloyd²

1973

Biochemical Journal

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“…11,1977 They believe that the increased catalase activity points to a possible protective mechanism that is related to the ability of the cells to survive long periods oftreatment under oxygen at high pressure. Gifford and Pritchard (17) demonstrate further that when oxygen under high pressure is put into the culture in a "catalase-rich" phase ofthe cells, the cells are able to survive the exposure. In view of the pronounced and specific effect of miconazole on the oxidative and peroxidative enzymes, as compared with the effect on hydrolases, we attach great importance to this observation, which might point to a possible mechanism of action of the drug.…”

Section: Discussionmentioning

confidence: 99%

Cytochemical and Biochemical Studies of Yeasts After In Vitro Exposure to Miconazole

Nollin

Belle

Goossens

et al. 1977

Antimicrob Agents Chemother

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Yeast cells exposed to different doses of the antimycotic agent miconazole revealed important cytochemical changes in the topographic distribution of the phosphatases. A strong effect was observed on the behavior of oxidative and peroxidative enzymes. Decreased cytochrome c oxidase and peroxidase activity and increased catalase activity were seen after treatment with a fungistatic dose ofmiconazole, whereas a complete disappearance ofthese enzymes was observed after treatment with a minimal fungicidal dose of miconazole. This was in complete agreement with the quantitative biochemical data. A hypothesis is advanced concerning the possible involvement of peroxidase and catalase in the mechanism of action of this drug., is an imidazole nitrate that has demonstrated broad-spectrum activity against most pathogenic fungi and gram-positive bacteria (7,10,18,19,36). The studies on the uptake and utilization of substances in Candida albicans by Van den Bossche (37) indicated that miconazole induced changes in the permeability of the plasmalemma and the cell wall. At the ultrastructural level, C. albicans cells show changes in a dosedependent manner when grown in the presence of 10`8 to 10-M concentrations of miconazole. These changes range from slight alterations in the cell periphery and increase in the number of peroxisomes and lipid globules, to progressive cytoplasmic deterioration, prominent shape changes, and complete cellular necrosis (11, 12; S. De Nollin, Ph.D thesis, University of Brussels, Brussels, Belgium, 1976). Recent investigations with scanning and transmission electron microscopy (12) on C. albicans cultures treated with a fungicidal dose of miconazole (10-4 M) have shown that the sequence of alterations differs totally from that obtained with lower-dose treatments.The cytochemistry of untreated yeast cells has already been described by several authors (2, 3, 13, 22, 40; S. De Nollin, Ph.D. thesis, 1976). In earlier experiments (16, 13), we tried to optimize the preparatory conditions for the cytochemical examination of yeasts cells by using a modification of the conventional procedure for preservation. This yields, besides a good micromorphology of the cells, sufficient enzyme activities and allows an adequate penetration of substrates and captation ions during the incubation. For the biochemical studies, Van Belle, Goossens, and Van Roy (in preparation) have recently developed a method for obtaining adequate homogenization of the very rigid cells of yeast, thereby yielding reliable enzyme activities that are directly proportional to the number of cells (more than 99.9% of the cells are thoroughly homogenized). Using these modifications of the cytochemical and biochemical preparative techniques, we have tried in this study to evaluate the effects of miconazole on the activities and the distribution pattem of phosphohydrolases and of oxidative and peroxidative enzymes in C. albicans and Saccharomyces cerevisiae. Our particular aim was to see whether there was any correlation between the observed morph...

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“…12 Gifford and Pitchard describes responses of Candida utilis to hyperbaric oxygen. 13 Cultures of organisms in an exponential growth phase did not undergo any further development when exposed to 10 ATA oxygen. When the exposure was continued for several days, all cells died.…”

Section: The Effects Of Hyperbaric Oxygen On Fungimentioning

confidence: 96%

The Role of Hyperbaric Therapy in the Growth of Candida Albicans

Widiyanti

2013

IJTID

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Background: Candida albicans is opportunistic pathogen fungi which cause many disease in human such as reccurrent apthous stomatitis, skin lesions, vulvavaginitis, candiduria and gastrointestinal candidiasis. Aim: Infection mechanism of C. albicans is very complex including adhesion and invasion, morphology alteration from khamir form cell to filamen form (hifa), biofilm forming and the avoidance of host immunity. Method: The ability of C. albicans to adhere to the host cell which is act as important factor in the early colonization and infection. Result: The phenotype alteration to be filament form let the C. albicans to penetrate to the epithelium and play important role in infection and separation C. Albicans to the host cell. Hyperbaric oxygen is the inhalation of 100 percent oxygen inside hyperbaric chamber that is pressurized to greater than 1 atmosphere (atm). Conclusion: The organism was found to be inhibited within a pressure/time range well tolerated by human subjects, suggesting that hyperbaric oxygen might be used successfully in treating human candidiasis.

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Toxicity of Hyperbaric Oxygen to Yeasts Displaying Periodic Enzyme Synthesis

Cited by 7 publications

References 4 publications

Oscillations of enzyme activities during the cell-cycle of a glucose-repressed fission-yeast Schizosaccharomyces pombe 972h

Oscillations of enzyme activities during the cell-cycle of a glucose-repressed fission-yeast Schizosaccharomyces pombe 972h

Cytochemical and Biochemical Studies of Yeasts After In Vitro Exposure to Miconazole

The Role of Hyperbaric Therapy in the Growth of Candida Albicans

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