Author/Editor		Strmole, Tadeja
Title		Halotolerantne askomicetne kvasovke osamljene iz arktičnega okolja
Translated title		Halotolerant ascomycetous yeast isolated from arctic environment
Type		monografija
Place		Ljubljana
Publisher		Medicinska fakulteta
Publication year		2007
Volume		str. 144
Language		slo
Abstract		Until recently it was believed that extremely cold environments on Earth are inhabited almost exclusively by procariotic microorganisms. In 2001 and 2003 Gunde-Cimerman isolated extremophilic fungi from various ecological niches (glacial ice, sea ice, sea water) in the coastal Arctic environment (Spitzbergen, Norway). The dominant taxa were ascomycetous and basidiomycetous yeasts, melanized fungi, mainly represented by the genera Cladosporium and Aureobasidium and different species of the genus Penicillium. Amongst 359 isolated yeasts we determined the ascomycetous ones using physiological tests (urease, DBB colour reaction). 76 ascomycetous yeasts we taxonomically identified using: i) morphological methods (growth on solid media, microscopy of sexual and asexual structures), ii) physiological methods (fermentation, assimilation, production of starch-like compaunds) and iii) molecular methods (MSP-PCR, rDNA sequencing). In order to determine halotolerant and xerophilic species, yeasts were grown on high salt or high sugar media with consequentially lowered water activity. We established that Arctic environment is mainly inhabited by Candida parapsilosis, Debaryomyces hansenii, Debaryomyces maramus, Metschnikowia bicuspidata, Metschnikowia zobellii, Pichia guilliermondii and Protomyces inouyei, and also two new species, not yet scientifically known. Halotolerant yeasts were represented by C. parapsilosis, D. hansenii and P. guilliermondii. These three species together with D. maramus, M bicuspidata, M zobellii and two new species, Candida galli-Like and Candida rugosa-like, were characterized as xerophilic taxons.
Descriptors		YEASTS HALOBACTERIALES