RepSeq is a web-based database and application designed to identify amino acid repeat-containing proteins in lower eukaryotic pathogens. The database, accessible via a web interface, provides tools for both individual and cross-species proteome analyses. The RepSeq algorithm, written in PERL, can identify both perfect and mismatch repeats, with a high sensitivity and specificity. It uses a sliding window to search for repeated sequences within protein sequences, counting 6-residue motifs and recording their positions and lengths. The database includes 13 proteomes from various sources, primarily parasitic protozoa, and allows users to upload their own proteomes for analysis. The database is particularly useful for experimental biologists studying pathogenicity and virulence factors in protozoan parasites, as it provides a comprehensive subset of proteins for further analysis, including expression profiling and functional characterization.RepSeq is a web-based database and application designed to identify amino acid repeat-containing proteins in lower eukaryotic pathogens. The database, accessible via a web interface, provides tools for both individual and cross-species proteome analyses. The RepSeq algorithm, written in PERL, can identify both perfect and mismatch repeats, with a high sensitivity and specificity. It uses a sliding window to search for repeated sequences within protein sequences, counting 6-residue motifs and recording their positions and lengths. The database includes 13 proteomes from various sources, primarily parasitic protozoa, and allows users to upload their own proteomes for analysis. The database is particularly useful for experimental biologists studying pathogenicity and virulence factors in protozoan parasites, as it provides a comprehensive subset of proteins for further analysis, including expression profiling and functional characterization.