A computer system and method using mass spectrometry data and a protein database for identifying unknown proteins

摘要

The present invention relates to a computer system and a method for selecting one or more candidate proteins from a plurality of proteins stored in a database. The invention relates in particular to a method for providing a measure applicable in selecting proteins in a database storing a numerical representation of theoretical mass spectrum for a plurality of proteins. The method comprises the steps of: extracting noise-free mono-isotopic peptide peaks from the numerical representation of the mass spectrum to be identified based on a numerical representation of a mass spectrum of a protein to be identified in the form of corresponding values of entity mass/electric charge and intensity, thereby providing, if possible, a list of selected peaks selecting at least one candidate protein from the database, said candidates being selected based on a closeness-of-fit algorithm providing a set of peak matches between the list of selected peaks and peaks of the candidate proteins, determining the probability for the set of peak matches to occur, thereby providing a measure applicable in selecting protein candidates. The present invention also relates to a graphical user interface rendering utilisation of the method easy.