scholarly journals On the Structures of Mitochondria and Intracytoplasmic Membrane System of Candida albicans

1966 ◽  
Vol 21 (9) ◽  
pp. 533-540 ◽  
Author(s):  
Kazuo IWATA ◽  
Tsunehiko HIRATA
Author(s):  
C. L. Scott ◽  
W. R. Finnerty

Acinetobacter sp. HO-1-N, a gram-negative hydrocarbon oxidizing bacterium previously designated Micrococcus cerificans, has been shown to sequester the hydrocarbon into intracytoplasmic pools as a result of growth on this substrate. In hydrocarbon grown cells, an intracytoplasmic membrane system was also observed along with a doubling of cellular phospholipids (Z). However, using conventional dehydration and embedding procedures in preparing thin sectioned material, the hydrocarbon is extracted from the cells. This may lead to structural distortion, consequently, the freeze-etch technique was applied to preserve the integrity of the cell.


1984 ◽  
Vol 30 (5) ◽  
pp. 594-604 ◽  
Author(s):  
G. D. Sprott ◽  
L. C. Sowden ◽  
J. R. Colvin ◽  
K. F. Jarrell ◽  
T. J. Beveridge

The frequency of intracytoplasmic membranes in several methanogens grown on H2–CO2 varied with the conditions of growth and varied from one strain to another. Methanobacterium thermoautotrophicum often generated large numbers of intracytoplasmic membranes, while Methanospirillum hungatei produced these membranes only rarely. Conditions allowing for rapid growth, including optimal temperature and high agitation rates, increased the production of intracytoplasmic membranes. These membranes consisted mainly of vesicles composed of one or several membrane layers, often positioned in the central region of the cytoplasm. Several mesophilic methanogens could be grown such that intracytoplasmic membranes were rarely or never observed in thin section or in replicas of cross-fractures from frozen cells. Since high rates of methane synthesis still occurred in these cultures, it follows that the intracytoplasmic membrane system is not a necessary organelle for methane formation in these strains. Negative staining for electron microscopy is not an accurate method to visualize intracytoplasmic membranes in these bacterial cells.


2015 ◽  
Vol 65 (Pt_10) ◽  
pp. 3527-3534 ◽  
Author(s):  
Ashraf Khalifa ◽  
Chol Gyu Lee ◽  
Takuya Ogiso ◽  
Chihoko Ueno ◽  
Dayéri Dianou ◽  
...  

An aerobic, methane-oxidizing bacterium (strain RS11D-PrT) was isolated from rice rhizosphere. Cells of strain RS11D-PrT were Gram-stain-negative, motile rods with a single polar flagellum and contained an intracytoplasmic membrane system typical of type I methanotrophs. The strain utilized methane and methanol as sole carbon and energy sources. It could grow at 20–37 °C (optimum 31–33 °C), at pH 6.8–7.4 (range 5.5–9.0) and with 0–0.2 % (w/v) NaCl (there was no growth at above 0.5 % NaCl). pmoA and mmoX genes were present. The ribulose monophosphate and/or ribulose bisphosphate pathways were used for carbon assimilation. Results of sequence analysis of 16S rRNA genes showed that strain RS11D-PrT is related closely to the genera Methylococcus, Methylocaldum, Methyloparacoccus and Methylogaea in the family Methylococcaceae. The similarity was low (94.6 %) between strain RS11D-PrT and the most closely related type strain (Methyloparacoccus murrellii R-49797T). The DNA G+C content was 64.1 mol%. Results of phylogenetic analysis of the pmoA gene and chemotaxonomic data regarding the major cellular fatty acids (C16 : 1ω7c, C16 : 0 and C14 : 0) and the major respiratory quinone (MQ-8) also indicated the affiliation of strain RS11D-PrT to the Methylococcus–Methylocaldum–Methyloparacoccus–Methylogaea clade. On the basis of phenotypic, genotypic and phylogenetic characteristics, strain RS11D-PrT is considered to represent a novel genus and species within the family Methylococcaceae, for which the name Methylomagnum ishizawai gen. nov., sp. nov. is proposed. The type strain is RS11D-PrT ( = JCM 18894T = NBRC 109438T = DSM 29768T = KCTC 4681T).


1989 ◽  
Vol 263 (2) ◽  
pp. 573-579 ◽  
Author(s):  
C A Hitchcock ◽  
K Dickinson ◽  
S B Brown ◽  
E G V Evans ◽  
D J Adams

The purification of cytochrome P-450-dependent 14 alpha-sterol demethylase (P-450DM) from the important opportunistic fungal pathogen, Candida albicans, is described. Optimal purification (875-fold) was achieved by extracting the cytochrome from microsomes with sodium cholate followed by hydroxyapatite, octyl-Sepharose and CM-Sepharose chromatographies, giving a cytochrome preparation of 17.5 nmol/mg of protein. By the use of SDS/polyacrylamide-gel electrophoresis the cytochrome was judged to be highly purified on the basis of Coomassie Brilliant Blue staining of protein. The Mr of P-450DM was estimated to be 51,000. The absorption spectrum of oxidized P-450DM was characteristic of a low-spin cytochrome, and its reduced CO complex had a Soret absorption peak at 447 nm. When reconstituted in a model membrane system of dilauroylphosphatidylcholine with NADPH and O2, P-450DM catalysed the complete 14 alpha-demethylation of lanosterol, which was inhibited by CO. The cytochrome appeared to have a high degree of substrate specificity; it was unable to oxidize a number of xenobiotic compounds in the reconstituted assay.


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