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L J Wickerham

Publications and source records attributed to L J Wickerham.

At least 19 recordsLinked to original sources
PubMed1970

Sexual reproduction in Candida lipolytica.

Candida lipolytica is a rather common yeast isolated more frequently from substrates containing lipids or proteins, such as dairy products, than from substrates rich in sugars. This species assimilates hydrocarbons and is currently being studied for its potential to convert petroleum into yeast cells for use in feeds and foods. We have found C. lipolytica to exist in nature primarily in the heterothallic haploid state. When appropriate strains of opposite sex are mixed on a suitable sporulation medium, conjugation occurs followed by the production of ascospores. Since heterothallism permits laboratory control of hybridization, this characteristic of C. lipolytica enhances the possibility of im proving its strains for technological uses.

Candida↗
PubMed1962

Formation of Extracellular Sphingolipids by Microorganisms: IV. Pilot-Plant Production of Tetraacetylphytosphingosine by Hansenula ciferrii.

Tetraacetylphytosphingosine (TAPS) formation by the F-60-10 mating type strain of the yeast Hansenula ciferrii, previously observed on agar plates, has been shown to take place in submerged cultures. The optimal conditions for TAPS formation, and the correlation of TAPS production and sugar utilization under aerobic conditions, were studied in 10-liter fermentors. For each gram of glucose consumed, 5 mg of TAPS were formed; for each gram of yeast solids produced, 15 mg of TAPS were synthesized. A 750-liter pilot-plant run yielded 175 g of crude TAPS, which were obtained by hexane extraction of centrifuged yeast cells.

Journal Article↗
PubMed1961

PHYLOGENY OF PHOSPHOMANNAN-PRODUCING YEASTS II. : Phosphomannan Properties and Taxonomic Relationships.

Slodki, M. E. (U. S. Department of Agriculture, Peoria, Ill.), Lynferd J. Wickerham, and M. C. Cadmus. Phylogeny of phosphomannan-producing yeasts. II. Phosphomannan properties and taxonomic relationships. J. Bacteriol. 82:269-274. 1961.-Primitive species of yeasts belonging to the genus Hansenula and closely related genera produce extracellular phosphorylated mannans from glucose. These polysaccharides, called phosphomannans, contain mannose and mannose 6-phosphate as the only carbohydrate constituents. A comparative study of these phosphomannans yielded valuable phylogenetic information bearing on the yeasts that produce them. Strains of the same species elaborate similar phosphomannans. An inverse relationship was found between the evolutionary status of the organism and the degree of phosphorylation of its phosphomannan.

Journal Article↗