xMAN

XMAn (Unknown Mutation Analysis) is a specialized database designed to facilitate the identification of protein sequence alterations using tandem mass spectrometry (MS/MS) data. The database contains a comprehensive collection of mutated human peptide sequences in FASTA format, which can be used with search engines to match experimental MS/MS data with theoretical sequences.

Key features of XMAn include:

1. Extensive coverage: XMAn v2 comprises 2,539,031 unique mutated entries derived from 17,599 human proteins. This extensive coverage allows for a thorough analysis of potential protein sequence variations.

2. Mutation types: The database includes 2,377,103 missense mutations (single amino acid substitutions) and 161,928 nonsense mutations (premature stop codons), enabling the identification of various types of protein sequence alterations.

3. FASTA format: The mutated peptide sequences are stored in FASTA format, a standard text-based format for representing either nucleotide or peptide sequences. This format is compatible with many bioinformatics tools and search engines.

4. Integration with search engines: XMAn can be combined with search engines that match experimental MS/MS data to theoretical sequences from a database, allowing researchers to identify peptides with amino acid sequence variations by comparing the experimental data with the mutated sequences in XMAn.