The tombstones at the Monumental Cemetery of Milano select for a specialized microbial community

• Published in: International biodeterioration & biodegradation Vol. 164; p. 105298
• Main Authors: Gambino, Michela, Lepri, Gloria, Štovícek, Adam, Ghazayarn, Lusine, Villa, Federica, Gillor, Osnat, Cappitelli, Francesca
• Format: Journal Article
• Language: English
• Published: Barking Elsevier Ltd 01.10.2021; Elsevier BV
• Subjects: Bacteria; Biodeterioration; Biofilms; Cyanobacteria; Microbial activity; Microbial diversity; Microbiomes; Microorganisms; Rock; Soils; Stone; Stress; Subaerial biofilm; Tombstones; Microbial diversity; Subaerial biofilm; Rock; Stone; Stress; Cyanobacteria
• ISSN: 0964-8305; 1879-0208
• DOI: 10.1016/j.ibiod.2021.105298

Subaerial biofilms play a central role in the ecology and biodeterioration of many outdoor monuments and pieces of art. It is well established that microorganisms can face a broad range of stress by living in these subaerial environments, but their origin, taxa determinants and physiological traits are debated. Here, we hypothesized that the bacteria forming these biofilms originate from the surrounding air and soil and that the selective pressure of a life on rocks shapes the community. To verify this hypothesis, we studied the microbial communities of nine tombstones of the Monumental Cemetery of Milano, by collecting samples in three seasons. We analyzed the structure of these subaerial biofilms, compared them with the bacteria identified in the surrounding air and soil and found that only few rare taxa are shared among the three compartments and have been selected by the stone environment. In addition, we considered which parameters - among temperature, humidity, light, season and lithotype - concur to structure the microbial community. •Stone communities differ dramatically from surrounding soil and air communities.•Stone microbial communities are richer than gravel soil and air communities.•Abundance of Cyanobacteria characterize stone microbial communities.•Stone communities share few rare taxa with soil and air.•Lithotype is the major determinant of the stone community structure.