Sulfide Determination
Mostrando 25-29 de 29 artigos, teses e dissertações.
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25. Redox Potentials of Certain Vitamins K: Implications for a Role in Sulfite Reduction by Obligately Anaerobic Bacteria
Redox potentials of a menaquinone (MK-6), isolated in earlier researches from two species of the obligately anaerobic genus, Desulfovibrio, as well as two other vitamins K2—menaquinones (MK-5) and (MK-9)— have been determined polarographically. The measurements have been validated by determination of redox potentials of 1,4-naphthoquinone and vitamin K1
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26. Chemical conversion of cytidine residues into 4-thiouridines in yeast tRNAPhe. Determination of the modified cytidines.
Treatment of yeast phenylalanine tRNA with pressurized hydrogen sulfide results in conversion of cytidine residues into 4-thiouridine residues. Under conditions leading to an average modification of one cytidine per tRNA molecule 9 positions are thiolated. The 4-thiouridine residues are distributed along the tRNA molecule. Four of the reactive cytidines are
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27. General approach to bacterial nutrition: growth factor requirements of Moraxella nonliquefaciens.
A general procedure was devised for the determination of growth factor requirements of heterotrophic bacteria based upon identification of individual nutrients as they are successively depleted from a limited quantity of complex medium. By using this approach, it was possible to develop a defined medium for growth of Moraxella nonliquefaciens that contained
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28. Microcalorimetric studies of the growth of sulfate-reducing bacteria: energetics of Desulfovibrio vulgaris growth.
The metabolism of Desulfovibrio vulgaris Hildenborough grown on medium containing lactate or pyruvate plus a high concentration of sulfate (36 mM) was studied. Molecular growth yields were 6.7 +/- 1.3 and 10.1 +/- 1.7 g/mol for lactate and pyruvate, respectively. Under conditions in which the energy source was the sole growth-limiting factor, we observed the
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29. Use of Poisons in Determination of Microbial Manganese Binding Rates in Seawater
A method was developed to determine whether microorganisms mediate the precipitation of manganese(II) in the marine environment. Radioactive 54Mn(II) was used as a tracer to measure the precipitation (binding and oxidation) of Mn(II) [i.e., the 54Mn(II) trapped on 0.2-μm membrane filters] in the presence and absence of biological poisons. A variety of antib