Extracellular hydrolytic enzymes produced by yeasts from Antarctic lichens

Abstract

In the Antarctic environment, yeasts are versatile eukaryotes that have shown wide dispersion in different substrates, producing active enzymes in extreme conditions, but their relevance in biotechnological applications is largely unknown. The aim of this study was to evaluate the production of extracellular hydrolases by yeasts isolated from Antarctic lichens and molecularly identify these isolates. From a total of 144 isolates on the screening, 109 (76%) produced at least one of the hydrolases tested, with most activities for proteases 59 (41%), cellulases 58 (40%), esterases 57 (39%), lipases 29 (20%), amylases 23 (16%) and pectinases 20 (14%). Among these isolates, 76 were identifi ed, most belonged to the phylum Basidiomycota (n=73) with the dominance of Vishniacozyma victoriae (n=27), Cystobasidium alpinum (n=3), Mrakia niccombsii (n=3), Cystobasidium laryngis (n=2), Bannozyma yamatoana (n=2), Holtermanniella nyarrowii (n=2), and Glaciozyma martinii (n=2). This study is the fi rst one reporting extracellular enzyme production by yeasts isolated from thallus of the species of Antarctic lichens Lecania brialmontii, Polycauliona candelaria, Usnea capillacea, Cladonia metacorallifera, and Polycauliona regalis. With these data, it's possible to confi rm lichens as a source of hydrolase-producing yeasts, reinforcing the potential of these microorganisms in bioprospecting studies of catalytic molecules from polar regions that may be useful in promising biotechnological applications.

Fungal and fungal‐like diversity present in ornithogenically influenced maritime Antarctic soils assessed using metabarcoding

“…Among the 97 genera reported, saprophytes were dominant in all sampling sites, followed by those considered to be symbionts and pathogens of plants and animals. Our results are consistent with recent fungal metabarcoding studies in different Antarctic environments [16, 36–38, 56, 57, 65–67]. Schütte et al [68] and Gonçalves et al [40] suggested that a proportion of the kingdom Fungi can colonize the cold environments of the polar regions, where they degrade organic matter at low temperatures, producing organic breakdown products and making these available to other organisms in the trophic web.…”

“…Leucosporidium includes yeasts commonly inhabiting low-temperature environments of polar and temperate regions [62]. In Antarctica, Leucosporidum taxa have been detected, mainly in traditional culturing studies, in seawater [60] and associated with the plant Colobanthus quitensis [59] and lichen thalli [65] in maritime Antarctica.…”