Potential Innovative Tools for Heritage Conservation: A Novel RNA-FISH Probe and Antimicrobial Peptides for the...

Microorganisms such as Arthrobacter spp. are important agents of biodeterioration in cultural heritage (CH) environments, causing orange-yellow chromatic alterations and contributing to substrate degradation. This study evaluates two complementary tools for the rapid detection and mitigation of Arthrobacter spp.: a newly designed genus-specific RNA-fluorescence in situ hybridisation (FISH) probe (Art1420-Cy3) and an antimicrobial peptide fraction produced by Saccharomyces cerevisiae ISA 1028. The RNA-FISH probe Art1420-Cy3 showed high specificity and sensitivity, labelling 80-85% of Arthrobacter cells at 10% (v/v) formamide and enabling their detection by epifluorescence microscopy and flow cytometry. The peptide fraction exhibited pronounced bactericidal activity, reducing Arthrobacter culturability from ~10⁸ to ~10¹ CFU/mL within 48 h, while also inhibiting other biodeteriogenic microorganisms. Overall, these findings outline the basis for an integrated and CH-compatible approach that combines precise Arthrobacter cells detection and identification with targeted, biologically derived control. Although further validation using real heritage samples and application protocols specifically tailored to sensitive materials is required, this strategy shows strong potential as a sustainable alternative to conventional chemical biocides and as a practical framework for detecting and mitigating pigment-producing biodeteriogens in CH and other vulnerable environments.