| Attributs | Valeurs |
|---|
| type
| |
| Is Part Of
| |
| Subject
| |
| Title
| - Prediction of Posttranslational Modifications UsingIntact-Protein Mass Spectrometric Data
|
| has manifestation of work
| |
| related by
| |
| Author
| |
| Abstract
| - We present a Web-based application that uses whole-protein masses determined by mass spectrometry toidentify putative co- and posttranslational proteolyticcleavages and chemical modifications. The protein cleavage and modification engine (PROCLAME) requires asinput an intact mass measurement and a precursoridentification based on peptide mass fingerprinting ortandem mass spectrometry. This approach predicts mass-modifying events using a depth-first tree search, boundedby a set of rules controlled by a custom-built fuzzy logicengine, to explore a large number of possible combinations of modifications accounting for the experimentalmass. Candidates are saved during a search if they arewithin a user-specified instrument mass accuracy; thetotal number of possible candidates searched is based ona specified fuzzy cutoff score. Candidates are scored andranked using a simple probabilistic model. There isgenerally not enough information in an intact massmeasurement to determine a single unique protein characterization; however, the program provides utility byexpediting the identification of sets of putative eventsconsistent with the mass data and ranking them for furtherinvestigation. This approach uses a simple, intuitive rulebase and lends itself to discovery of unannotated posttranslational events. We have assessed the program withboth in silico-generated test data and with published datafrom an analysis of large ribosomal subunit proteins, bothfrom the yeast S. cerevisiae. Results indicate a highdegree of sensitivity and specificity in characterizingproteins whose masses resulted from reasonable proteolysis and covalent modification scenarios. The application is available on the web at http://proclame.unc.edu.
|
| article type
| |
| is part of this journal
| |
