|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1994 : ¥900,000 (Direct Cost : ¥900,000)
Fiscal Year 1993 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Dimorphism, the yeast-mycelium conversion, of the opportunistic fungus Candida albicans is of particular medical importance. Because it has been thought to have relevance to the pathogenesis of Candida infection. However, only a little was known about the mechanism of this phenomenon. To attack this problem in the aspect of metabolism, we attempted to compare the metabolism of glucose and other carbon sources between the two cell forms, yeast and mycelium, by a new type of analytical method, 13C NMR.We devised an original experimental system by employing newly isolated morphological mutants of C.albicans as a mycelium form for this purpose. By this, we were able to prepare both yeast and mycelium cells grown under the same cultural condition. First, 2-13C or 1-13C glucose was fed to both cell forms. It was found that the accumulation of arabitol, one of polyols produced by yeast form (wild type), drastically decreased in mycelium (mutant), although the consumption rate of glucose was roughly equal. This finding was confirmed by analysing the metabolism of 2-13C or 1-13C acetate in both cell forms. Furthermore, normal accumulation of arabitol in revertant (yeast) isolated from the mutant and decrease of arabitol production in another morphological mutant (mycelium) suggest the correlation of the metabolic change to the morphological change. Decrease of arabitol production implies the low activity of hexose monophosphate shunt, which supplies NADPH,reducing power, to many biosynthetic reactions. Relationship between cellular NADPH level and cell morphology of this fungus is next question.