Genomes from extreme life

NIZOVOY P; BELLORA N; MOLINÉ M; LIBKIND D

San Carlos de Bariloche

Congreso; 34 International Specialized Symposium on Yeasts; 2018

For long time extremophiles were terra incognita, since aggressive conditions of their ecological niches were considered dead zones. Nowadays it is well known that these places are inhabited by a wide spectrum of microorganisms that became valuable resources in biotechnology and interesting candidates when exploring life origin.Odd microorganisms cannot be studied by comparing their genomes with model organisms? (like Saccharomyces cerevisiae or Cryptococcus neoformans). Generating a good quality database of extreme life genomes is thus essential.In this work we sequenced yeast isolated from extremely  acidic, and high heavy metal polluted environments. Selection of strains was based on their outstanding metal and acid tolerance. Source origin was either anthropogenic (acid rock drainage from São Domingos mine in Portugal) or natural (argentinian acidic water bodies from Río Agrio-Lago Caviahue system -RALC-).Three portuguese strains were selected along with phylogenetically related strain exclusively found in RALC. These four Goffeauzyma?s strains (G. iberica, G. metallitolerans, G. aciditolerans and G. agrionensis), collectively known as  ARD ecoclade resulted in genomes ranging from 16 to 25 mbp with comparable number of putative genes predicted (mean 6.2k).Four strains belonging to an undescribed species that may represent the first report of an acidophilic yeast, were also sequenced (two portuguese strains and two RALC?s). Assemblies resulted in 20.3 mbp average, accounting for 7k number of putative genes.Coniochaeta fodinicola and Rhodotorula mucilaginosa, ubicuos strains but frequently found in these environments, were sequenced and their genomes analyzed for gene prediction.Genomes quality was assessed for all basidiomycetous strains by comparing genomic statistics and genome completeness was tested by looking for sets of eukaryotic core genes.Automatic and manually curated sets of annotations are being generated in order to explore possible genomic traits of their extreme tolerance, whether it was shaped in a natural or anthropogenic environment.