Correction to: Novel qPCR probe systems for the characterization of subaerial biofilms on stone monuments.

Purpose: A deep survey of biodeteriogen microorganisms reported on stone monuments in Europe has been performed based on the available literature dating back to over 30 years. The aim of the present study is to obtain accurate oligos for the characterization of subaerial biofilms on the basis of the most comprehensive collection of reports and case studies regarding subaerial biofilms, with particular regard to phototrophic and non-phototrophic bacteria, eukaryotic algae and molds. Methods: The obtained lists for eukaryotic algae, phototrophic and non-phototrophic bacteria and fungi were sorted by Genera and corresponding sequences in triplicate were downloaded by nucleotide database Genbank for a number of selected barcoding markers. On the basis of collected bibliometric diversity, multiple nucleotide alignments were produced and primers were designed for a qPCR assay. Result: Primers were designed on conserved regions flanking a variable region, specific for each of the studied groups of microorganisms. Standard curve for absolute quantification relative to each group were determined for four markers. Then, variable regions in the alignments were used to design fluorescent internal probes for qPCR aimed for a multiplex reaction in which relative abundance can be determined. Conclusion: The authors propose this kind of cost-effective approach in the study of biofilms for the estimation of algae, molds and bacteria both for direct in situ analysis and in vitro simulation.