Mrakiella cryoconiti gen. nov., sp. nov., a psychrophilic, anamorphic, basidiomycetous yeast from alpine and arctic habitats

Abstract

A novel psychrophilic basidiomycetous species is described in a new anamorphic genus as Mrakiella cryoconiti gen. nov., sp. nov.; the type strain of Mrakiella cryoconiti is strain A15T (=CBS 10834T =DSM 21094T). Two representatives were isolated from alpine glacier cryoconite and from northern Siberian sediment. Physiological and biochemical properties are similar to characteristics shared by members of the genus Mrakia, although sexual reproduction is absent. Mrakiella cryoconiti strains are psychrophilic and produce cold-active pectate lyase. Sequence analyses of the ITS and 26S rRNA D1/D2 regions indicated that these strains represent a distinct taxon within the Mrakia clade of the order Cystofilobasidiales, class Tremellomycetes and phylum Basidiomycota. On the basis of phenotypic and genotypic characteristics, Cryptococcus aquaticus (a member of the Mrakia clade) is transferred to the newly described genus as Mrakiella aquatica comb. nov.