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O H STALHEIM

Publications and source records attributed to O H STALHEIM.

5 recordsLinked to original sources
PubMed1964

CULTIVATION OF LEPTOSPIRAE. I. NUTRITION OF LEPTOSPIRA CANICOLA.

Stalheim, O. H. V. (University of Wisconsin, Madison), and J. B. Wilson. Cultivation of leptospirae. I. Nutrition of Leptospira canicola. J. Bacteriol. 88:48-54. 1964.-The nutrition of Leptospira canicola was investigated by use of synthetic media of suitable ionic strength. At an incubation temperature of 30 C, the minimal components were calcium, iron, magnesium, and ammonium ions, thiamine, and a fatty acid source; barium and strontium replaced calcium. Aspartic acid, glutamic acid, or methionine stimulated the rate and amount of growth; the best growth occurred in medium containing additional amino acids. Additions of cyanocobalamin or biotin permitted growth at 37 C. The stimulatory effects of added cyanocobalamin, biotin, pyridoxine, pantothenate, lipoic acid, or nicotinic acid were additive at 37 C, but not at 30 C. Fatty acids containing 14, 16, 17, or 18 carbon atoms supported growth; linoleic and linolenic acids were toxic. Glyceryl monooleate or trioleate, or Tween 40, 60, or 80 supported moderate to good growth; a mixture of monoolein and Tween 60, or Tweens 60 and 80 supported the best growth. Ten strains of L. canicola cultivated in a synthetic medium containing Tweens 60 and 80 attained cellular densities per ml of 10(7) to 4.0 x 10(7) organisms. L. canicola cells, resuspended in medium containing oleic-1-C(14) acid, incorporated label primarily into cellular lipids; a lesser amount was located in the protein fraction, and only trace amounts were found in the nucleic acid fraction. The rate of incorporation was not affected by added sodium acetate. L. canicola was found to have fatty acid decarboxylase activity.

Biotin↗
PubMed1964

CULTIVATION OF LEPTOSPIRAE. II. GROWTH AND LYSIS IN SYNTHETIC MEDIUM.

Stalheim, O. H. V. (University of Wisconsin, Madison), and J. B. Wilson. Cultivation of leptospirae. II. Growth and lysis in synthetic medium. J. Bacteriol. 88:55-59. 1964.-Differences were found in the ability of leptospirae to grow in a synthetic medium; 43 strains, consisting of 16 serotypes, were tested and designated as either type I or type II. Type I leptospirae did not grow; type II grew and could be subcultured. The lytic effect of several lipids was measured with Leptospira pomona and L. canicola as representatives of type I and II leptospirae, respectively. L. pomona organisms were rapidly lysed by the monoolein of the synthetic medium and by other lipids as well; L. canicola cells were consistently more resistant. Although both organisms incorporated similar amounts of label when incubated in the presence of oleic-1-C(14) acid, only L. canicola grew in a modified, nonlytic synthetic medium. No differences were found in susceptibility to lysis between virulent and avirulent L. canicola organisms. Mutant type I leptospirae grown in synthetic medium had increased resistance to lysis by surface-active agents; they were poorly agglutinated by antiserum. The role of protein in the growth and antigenicity of type I leptospirae is discussed.

Bacteriolysis↗
PubMed1963

LEPTOSPIRAL COLONIAL MORPHOLOGY.

Stalheim, O. H. V. (University of Wisconsin, Madison) and J. B. Wilson. Leptospiral colonial morphology. J. Bacteriol. 86:482-489. 1963.-A sequence of apparent colonial types was observed with colonies of Leptospira pomona, L. canicola, L. icterohaemorrhagiae, and L. grippotyphosa in agar medium. Although some colonies of these serotypes had a different appearance initially, they eventually developed the mature or final appearance characteristic of the serotype. Colonies of freshly isolated, virulent cultures of L. pomona, L. canicola, and L. icterohaemorrhagiae were similar in appearance to colonies of avirulent strains of the same serotype. Additional studies of three stable and distinct colonial types of a laboratory strain of L. autumnalis revealed no differences in antigenicity, catalase activity, or mouse infectivity; however, differences in susceptibility to lysis by oleic acid were found. Although the colonial variants were stable during several in vitro variations, including growth in the presence of homologous antiserum and mutation to growth in a chemically characterized medium, rapid dissociation in vivo was found.

Animals↗