[A search for specific genes working on the process of mycelial growth in Candida tropicalis]

Abstract

Ethanol has been reported to cause mycelial growth in Candida tropicalis Pk233. Cultivation with ethanol in synthetic media containing glucose gave biphasic growth curves. During the first growth phase, there was an accumulation of swollen spherical yeast cells, instead of the oblong ones observed in the control culture, followed by the appearance of spherical daughter cells in chains. During the second growth phase, pseudohyphal cells appeared, projecting from the swollen yeast cells.Subtractive cloning was performed on cDNAs from both cultures to isolate genes expressed during the first phase, correlating to the process of ethanol induced hyphal growth. Subtracted cDNAs identified by homology search included a homologue of URP2 coding ribosomal protein S20, a homologue of nmt1 coding a regulator gene working on thiamine metabolism, and a homologue of MSG5 coding tyrosine phosphatase. Roles of these cloned homologues were discussed on the process of mycelial growth in this organism.