Comprehensive library of small proteins of different microbial species

Small proteins with fewer than 50 residues have largely been neglected in the field of proteomics, where the focus has been on larger proteins with multiple domains. Such a situation is understandable given that proteins with more domains could potentially perform more tasks or are endowed with larger number of sensory functions. In addition, larger proteins migrate slower in gel electrophoresis and liquid chromatography, and are thus easier to detect. This work sought to provide fundamental information about the ensemble of small proteins in different microbial species that have been concatenated into a single database of small proteins. Original data came from UniProt, which were parsed by an in-house MATLAB proteome analysis software to yield protein name, amino acid sequence, number of residues, molecular weight, and nucleotide sequence. Overall, the database of small proteins of different microbial species that spans different domains and across 72 species should find use in a variety of workflows seeking to gain a more holistic understanding of these small proteins.