Knowledge-based metabolite annotation tool: CEU Mass Mediator.

CEU Mass Mediator (CMM) is an on-line tool for aiding researchers when performing metabolite annotation. Its database is comprised of 279,318 real compounds integrated from several metabolomic databases including Human Metabolome Database (HMDB), KEGG and LipidMaps and 672,042 simulated compounds from MINE. In addition, CMM scores the annotations which matched the query parameters using 122 rules based on expert knowledge. This knowledge, obtained from the Centre for Metabolomics and Bioanalysis (CEMBIO) and from a literature review, enables CMM expert system to automatically extract evidence to support or refute the annotations by checking relationships among them. CMM is the first metabolite annotation tool that uses a knowledge-driven approach to provide support to the researcher. This allows to focus on the most plausible annotations, thus saving time and minimizing mistakes.