Metatranscriptomics reveals osmoregulatory strategies in pink biofilms on salt-weathered historic buildings in Austria (microbiomejournal.biomedcentral.com)

• First metatranscriptomics study on pink biofilms from salt-weathered built heritage
• Reveals active 'salt-in' and 'salt-out' osmoregulatory strategies in halophilic/halotolerant communities
• Identifies carotenoid biosynthesis pathways and stress defense mechanisms at the transcriptional level
• Highlights the need for domain-specific ribodepletion in archaea-rich metatranscriptomes

"A combined metagenomic and metatranscriptomic study of pink biofilms from two Austrian historic buildings (St. Virgil Chapel and Charterhouse Mauerbach) characterized active microbial communities and their molecular adaptations to high salinity. Key findings include the coexistence of 'salt-in' and 'salt-out' osmoregulatory strategies, diverse carotenoid biosynthesis pathways, and protective mechanisms against oxidative stress. The work highlights the value of metatranscriptomics for understanding active microbial processes in cultural heritage biodeterioration."