Matteo Calcagnile is a microbiologist with expertise in comparative genomics, comparative physiology, and comparative biochemistry. His Ph.D. thesis focused on the study of proteins with unknown functions in actinomycetes that have been conserved throughout evolution. Another major line of research involves pathogenic bacteria, such as Neisseria spp. and Salmonella spp., with particular attention to the molecular mechanisms that enable these organisms to colonize and infect host cells. Additionally, his work extends to microbial ecology, particularly in relation to ecosystem health and the analysis of microbial communities using metabarcoding techniques. Regardless of the specific research area, his approach is grounded in transcriptomics and comparative genomics, with the goal of understanding gene conservation and analyzing genomic contexts. This strategy has led to the identification and functional characterization of previously unannotated proteins. Notable examples include the PirA protein, a regulator of fatty acid metabolism in Streptomyces (https://doi.org/10.1016/j.ymben.2018.06.008; https://doi.org/10.3390/antibiotics10080947), and the Rid7C protein in Nonomuraea gerenzanensis, an endoribonuclease associated with the production of secondary metabolites in actinomycetes (https://doi.org/10.1128/jb.00462-21).