[Isoenzymes in two micromycetes species: taxonomic aspects]. / Isoenzymes chez deux espèces de micromycètes: aspect taxonomique.

Strains of different origins belonging to the two species of fungi imperfecti Cylindrocarpon ianothele and Calcarisporium arbuscula exhibit difference in their morphological or physiological appearances. We have attempted to determine if these variabilities could also be observed at the level of other phenotypic markers, the enzymes glucose-6-phosphate dehydrogenase, alcohol dehydrogenase, octanol dehydrogenase and malate dehydrogenase. Isozymes were separated by polyacrylamide gel electrophoresis and demonstrated isozyme variability as a function of growth and physiological states of a given strain. At the same state of development, the different strains exhibited highly heterogeneous isozyme groups which appear difficult to use for taxonomic purposes.

[Metabolism of nucleoside Y in a mutant strain auxotrophic for guanine (gua 2 su+) of Saccharomyces cerevisiae]. / Métabolisme du nucléoside Y chez une souche mutante auxotrophe à la guanine (gua 2 su+) de Saccharomyces cerevisiae.

The study of free nucleoside Y metabolism in a mutant strain of Saccharomyces cerevisiae seems to indicate that this component is not only provided by t-RNA Phe turnover. A peculiar physiologic activity-mitogenic type - may be connected with this observation.

[Evolution of cytoplasmic tRNAphe in a haploid strain of Saccharomyces cerevisiae]. / Evolution du t-RNAphé cytoplasmique chez une souche haploïde de Saccharomyces cerevisiae

The fluorescent modified Y nucleoside of phe-t-RNA has been evaluated during the development of a haploïd of yeast. Free Y nucleoside has been found in the cells during the growing logarithmic phase. It seems that the evolution of this compound is probably concerned with cellular division processes.