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W J NICKERSON

Publications and source records attributed to W J NICKERSON.

At least 19 recordsLinked to original sources
PubMed1963

REDUCTION OF SELENITE BY INTACT YEAST CELLS AND CELL-FREE PREPARATIONS.

Falcone, Giuseppe (Rutgers, The State University, New Brunswick, N.J.), and Walter J. Nickerson. Reduction of selenite by intact yeast cells and cell-free preparations. J. Bacteriol. 85:754-762. 1963.-Nonproliferating cell suspensions of Candida albicans rapidly reduced selenite to red, metallic selenium in the absence of added substrate. Cell suspensions reduced selenite optimally at pH 4.2. No added metabolite was found to be stimulatory; reduction was inhibited by methionine and formate as well as by fluoride, dinitrophenol, and certain sulfhydryl poisons. Cell-free preparations capable of reducing selenite were obtained from C. albicans and from baker's yeast disintegrated in a Hughes press. The enzymatic system had optimal activity at pH 7 with 10(-2)m selenite. Activity of the system was lost on dialysis but was restored upon the addition of dialyzable substances or of boiled, undialyzed extract.

Candida↗
PubMed1963

ENZYMATIC REDUCTION OF SELENITE.

Nickerson, Walter J. (Rutgers, The State University, New Brunswick, N.J.) and Giuseppe Falcone. Enzymatic reduction of selenite. J. Bacteriol. 85:763-771.-1963. Extraction of boiled yeast extract with n-hexane removed its ability to restore selenite-reducing capacity in dialyzed enzyme preparations obtained from baker's yeast or from Candida albicans. Menadione or thiodione substituted for the quinone(s) extracted by n-hexane. Active components of the water-soluble, dialyzable fraction of yeast extract included: glucose-6-phosphate, triphosphopyridine nucleotide, and glutathione. Selenite appears to be bound to protein through vicinal thiol groups, and to be released therefrom as metallic selenium after accepting four electrons.

Candida↗
PubMed1962

Antimicrobial activity of metal chelates of salts of 8-quinolinols with aromatic hydroxycarboxylic acids.

Thirty-seven metal chelate complexes of salts of 8-quinolinols with aromatic hydroxycarboxylic acids were screened by the disc-plate method against strains of five bacteria and five fungi. The copper (II) chelates of 8-quinolinolium salicylate and 8-quinolinolium-3'-hydroxy-2'-naphthoate showed outstanding antifungal and good antibacterial properties and appear to be potentially more economical than copper (II) 8-quinolinolate.

Acids↗
PubMed1962

Induction of yeast-like development in Mucor by carbon dioxide.

Bartnicki-Garcia, S. (Rutgers, The State University, New Brunswick, N. J.) and Walter J. Nickerson. Induction of yeastlike development in Mucor by carbon dioxide. J. Bacteriol. 84:829-840. 1962-Vegetative development of Mucor rouxii may follow either one of two patterns of morphogenesis (mold-yeast dimorphism), depending on the atmosphere of incubation. Under air or N(2), a filamentous (moldlike) growth developed, commonly followed by fragmentation of hyphae into spherical cells (arthrospores). Introduction of CO(2) into an anaerobic atmosphere induced development of spherical, budding yeastlike cells. Anaerobically, a pCO(2) of 0.3 atm or higher produced a purely yeastlike development. Presence of oxygen annulled the effect of CO(2) On germination, spores gave rise directly to either type of vegetative development, depending on the atmosphere of incubation. Induction of yeastlike development by CO(2) occurred in five strains of M. rouxii, and in most species of Mucor tested. M. subtilissimus, however, did not require CO(2); it developed in the yeastlike form under anaerobic conditions. Strains of Rhizopus grew under CO(2), but developed only filamentous mycelium. Members of other genera of Mucorales were unable to grow under an atmosphere of CO(2).

Carbon Dioxide↗
PubMed1962

Nutrition, growth, and morphogenesis of Mucor rouxii.

Bartnicki-Garcia, S. (Rutgers, The State University, New Brunswick, N.J.) and Walter J. Nickerson. Nutrition, growth, and morphogenesis of Mucor rouxii. J. Bacteriol. 84:841-858. 1962.-Mucor rouxii was grown under three different atmospheres of incubation: air, N(2), and CO(2) in parallel cultures. The atmosphere of incubation markedly affected nutritional requirements, growth, and morphogenesis. Absence of oxygen greatly reduced growth and increased the nutritional demands of the fungus. Presence of a high tension of CO(2) resulted in a change from filamentous to yeastlike morphogenesis. Aerobically, a large variety of carbon sources was utilized; anaerobically, only hexoses served to meet requirements for carbon and energy. Aerobically, various amino acids supported abundant growth; anaerobically, they were poorly utilized. Ammonium and nitrate ions were better sources of nitrogen for anaerobic growth. In general, incubation under either air or N(2) resulted in development of coenocytic filamentous mycelium, whereas incubation under CO(2) resulted in development of budding yeastlike cells. Variations in temperature and time of incubation, inoculum size, type and concentration of carbon source, type of nitrogen source, and presence of various substances with known action on fungal morphogenesis altered growth in many cases, but did not significantly affect the patterns of vegetative morphogenesis conditioned by each atmosphere of incubation. However, vegetative morphogenesis was strongly affected by addition of certain chelating agents. Yeastlike development of M. rouxii was prevented by ethylene-diaminetetraacetic acid (EDTA) in concentrations which were also partially inhibitory for growth; under these conditions, development was filamentous. Chemically related chelating agents were similarly active. The growth-inhibitory and morphogenetic effects of EDTA were reversed by transition-group metal ions. Yeastlike development of M. subtilissimus, which does not require CO(2) for its induction, was also inhibited by EDTA.

Amino Acids↗
PubMed1958

Respiratory metabolism of normal and divisionless strains of Candida albicans.

Respiration of a normal strain of Candida albicans was compared with that of a divisionless mutant which has a biochemical lesion such that metabolically generated hydrogen "spills over," during growth, for non-specific dye reduction. This waste is not at expense of growth, since both strains grow at essentially similar rates, nor at expense of respiration, since the mutant reduces oxygen more rapidly than the normal strain. Respiration in both strains is qualitatively similar, and seemingly unique among highly aerobic organisms in that it is not mediated by cytochrome oxidase. In resting cells of both strains, respiration is not only resistant to, but markedly stimulated by, high concentrations of cyanide, carbon monoxide, and azide. In contrast, growth of these yeasts is inhibited by low concentrations of cyanide and azide. Cytochrome oxidase could not be detected in cell-free preparations; reduced cytochrome c was not oxidized by such preparations. Cytochrome bands could not be observed in thick cell suspensions treated with reducing agents. However, incorporation of superoptimal levels of zinc and iron into the culture medium resulted in growth of cells possessing distinct cytochrome bands; respiration of these cells remained insensitive to cyanide, monoxide, and azide, and the bands were maintained in a reduced form on oxygenation. In the divisionless yeast, tetrazolium dyes compete with oxygen for reduction; this is not the case in the normal strain. The firmness with which hydrogen transfer is channeled in the latter for reduction of disulfide bonds (of importance in the division mechanism) and of oxygen, is contrasted with the lack of such control in the mutant.

Candida↗