Takashi Nakase

Serologic aspects on yeast classification

The classification of living beings is achieved by delimitation based upon their common properties. For this purpose, characteristics of living organisms should refer to those which have been mentioned or published. During such grouping processes, the morphology and growth, as well as biochemical properties reflecting the intermediate metabolism, are first taken into consideration. While there is no contradiction with respect to the classification of higher plants and animals, the criteria mentioned above are not always sufficient to classify microorganisms which are very minute and simple. Therefore, antigenic properties have been considered for the classification of bacteria, mainly pathogenic, but not as yet for yeasts. Furthermore, the serological characteristics of yeasts presented by several investigators (1, 28) have not been routinely adopted as appropriate tools for the classification as have not the GC contents of the DNA of yeasts (14), the coenzyme Q system (35), and the proton magnetic resonance (PMR) spectra of cell wall polysaccharides (7), although the chemical composition of the yeast cell or cell wall is considered to be of prime importance in indicating the relationships among various yeasts. This paper deals with the experimental results of antigen analyses of yeasts, rapid identification recently performed and serological characteristics in the classification of yeasts.

Fermentation of n-Paraffins by Yeast: Part III. α-Ketoglutarate Productivity of Various Yeast

α-Ketoglutarate productivity from n-paraffins of 141 strains of identified yeasts was studied. Among the strains tested, only strains of Candida lipolytica exclusively showed a high ability to produce α-ketoglutarale.It was also observed that these strains of Candida lipolytica required thiamine for their growth and that exegenous thiamine stimulated the activity of α-ketoglutarate dehydrogenase of Candida lipolytica AJ 5004.From these results, relationship between thiamine requirement and α-ketoglutarate productivity of Candida lipolytica was discussed.α-Ketoglutarate fermentation by representative strains of Candida lipolytica was also carried out.