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Biomedical subjects

O Wyss

Publications and source records attributed to O Wyss.

At least 37 records · Page 2Linked to original sources
PubMed1968

Effect of ion concentration on the rupture and survival of Azotobacter cysts.

The ability of ethylenediaminetetraacetic acid (EDTA) and dipicolinic acid (DPA) to rupture Azotobacter cysts was directly related to the molarity of the reaction mixture. Cysts were not ruptured at concentrations above 0.15 m (NaCl or phosphate). These higher salt concentrations prevented the formation of metallo:EDTA (or DPA) chelate complexes. Sudden shifts in the tonicity of NaCl or phosphate mixtures induced cyst rupture in the absence of EDTA. The effect of these mechanisms on the survival and germination of Azotobacter cysts in the soil is discussed.

Azotobacter↗
PubMed1967

Biotin-deficient growth of Bacillus polymyxa.

When Bacillus polymyxa, a wild-type biotin auxotroph, is grown in biotin-deficient medium, a retardation of cell division and consequential cell elongation are the initial detectable consequences of limited biotin. Subsequent events in biotin-deficient cells include, in chronological order: inhibition of net ribonucleic acid (RNA) synthesis and a simultaneous arithmetical accumulation of protein; loss of net RNA, deoxyribonucleic acid, and protein synthesis; morphological aberration, death, and lysis. Incorporation studies employing (32)P-phosphate and (14)CO(2) demonstrate an initial selective inhibition of net ribosomal RNA synthesis over that of ribosomal protein or total protein. Biotin could not be replaced by various extracts from which biotin had been removed, nor could osmotic stabilizers be found which could prevent lysis of the culture.

Bacillus↗
PubMed1966

Chelation effects on Azotobacter cells and cysts.

Goldschmidt, Millicent C. (University of Texas, Austin), and Orville Wyss. Chelation effects on Azotobacter cells and cysts. J. Bacteriol. 91:120-124. 1966.-Ethylenediaminetetraacetate (EDTA) is very toxic to Azotobacter in the presence of nitrogen compounds that form complexes with it. This appears to be due to stronger chelation of certain metal ions by the complex. When such complexes of EDTA and nitrogen compound are absent, Azotobacter cysts can be ruptured by chelation without being killed. The lethal action as well as the cyst rupture is modified by the presence of salts.

Azotobacter↗
PubMed1962

ENZYME ASSOCIATED WITH BACTERIOPHAGE INFECTION.

Eklund, Curtis (The University of Texas, Austin) and Orville Wyss. Enzyme associated with bacteriophage infection. J. Bacteriol. 84:1209-1215. 1962.-A capsule-digesting enzyme was formed when azotobacter cells were infected with bacteriophage. The enzyme appeared in the medium when the phages lysed the cells. By disrupting phage-infected cells prematurely, it was shown that enzyme formation in the bacterium began shortly after invasion. The amount of enzyme formed was far in excess of that incorporated into the new phages. The enzyme was concentrated from the lysate, and its activity was measured under a variety of conditions.

Journal Article↗