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P Margalith

Publications and source records attributed to P Margalith.

14 recordsLinked to original sources

Ethanol fermentation by nystatin-resistant strains of Saccharomyces cerevisiae.

Nystatin-resistant mutants of haploid and polyploid strains of Saccharomyces cerevisiae were isolated by plating on gradient plates with increasing nystatin concentrations (60-3000 U/ml). Some of the mutants were defective in ergosterol biosynthesis, and produced zymosterol and cholestatetraenol-like sterols. Those mutants which do not form ergosterol produce less ethanol than the parent strains. They also had lower viability during fermentation of glucose solutions (8-13% vs. 33-47%). This became more pronounced in fermentations of higher concentrations of glucose. A nystatin-resistant but ergosterol-forming mutant had a similar fermentation capacity to the parent strain.

Chromatography, Thin Layer↗

Effect of glucose on carbon dioxide assimilation and substrate oxidation by Ferrobacillus ferrooxidans.

Ferrobacillus ferrooxidans, grown on either elemental sulfur or ferrous sulfate, was able to use either substrate as an energy source for the assimilation of CO(2). In both cases, 0.01 mumole of carbon was incorporated per mumole of oxygen utilized. Glucose inhibited substrate oxidation and CO(2) fixation. Sulfur and iron oxidation were inhibited 5 to 15% and 40 to 50%, respectively, in the presence of 10% glucose. Under the same conditions, CO(2) assimilation was inhibited 50% with elemental sulfur as the energy source, and was almost totally inhibited when ferrous iron was used.

Bacteria↗

Sulfur oxidation by the iron bacterium Ferrobacillus ferrooxidans.

Margalith, P. (Syracuse University, Syracuse, N.Y.), Marvin Silver, and D. G. Lundgren. Sulfur oxidation by the iron bacterium Ferrobacillus ferrooxidans. J. Bacteriol. 92:1706-1709. 1966.-Sulfur and iron oxidation has been studied manometrically by use of Ferrobacillus ferrooxidans grown on either elemental sulfur or ferrous iron as the primary energy source. The iron-oxidizing enzyme was shown to be constitutive, since iron was oxidized as rapidly by sulfur-grown cells as by iron-grown cells. Sulfur-grown cells had a better capacity for oxidizing sulfur than did iron-grown cells; however, no lag in oxidation was seen in either case. The sulfur-oxidizing system was not inducible, and it is suggested that the different oxidative capacities are due to the heterogeneous mixture of cell types in the culture population.

Bacteria↗

Production of egg yolk coloring material by a fermentation process.

Rhodotorula mucilaginosa was cultivated in a yeast propagator, for the production of biomass and carotenoids. A spray-dried preparation of the yeast was incorporated into the diets of laying chickens for the promotion of egg yolk color. Several aspects of the effect of media on growth and carotenogenesis of pigmented yeast were examined. Addition of 1 to 2% of Rhodotorula yeast to the feeding mixture considerably improved egg yolk color. The possibility of using carotenogenic yeasts as a feed supplement is suggested.

Animals↗