Characterization of the archaeal and fungal diversity associated with gypsum efflorescences on the walls of the decorated Sorcerer's prehistoric cave

Purpose This study focuses on analysis of the archaeal and fungal diversity associated with gypsum efflorescences damaging the walls of the Sorcerer's prehistoric cave registered as a world cultural heritage site. Method Archaeal 16S rDNA and fungal internal transcribed spacer (ITS) clone libraries were constructed and analysed. Results Two thaumarchaeotal OTUs belonging to the Nitrososphaeraceae family dominated the archaeal community (100% of clones). Nitrososphaeraceae are obligate aerobic, chemolithoautotrophic organisms that derive their energy from the oxidation of ammonia and may contribute to primary productivity in the cave. Seven fungal OTUs belonging to Ascomycota and one belonging to Basidiomycota were present. The Cordycipitaceae family, mainly represented by entomophilous fungi, dominated the analysis (66.7% of clones). Conclusion We show that archaeal and fungal OTUs are associated with gypsum efflorescences damaging the walls of the Sorcerer's cave. The role of these microorganisms in the deterioration of the walls of the cave remains to be determined.