Utilities for Mass Spectrometry Analysis of Proteins (UMSAP): Fast post-processing of mass spectrometry data.

RATIONALE: Mass spectrometry (MS) is an invaluable tool for the analysis of proteins. However, the sheer amount of data generated in MS studies demands dedicated data-processing tools that are efficient and require minimal user intervention.

METHODS: Utilities for Mass Spectrometry Analysis of Proteins (UMSAP) is a graphical user interface designed for efficient post-processing of MS result files. The software is written in Tcl/Tk and can be used in Windows, OS X or Linux. No third party programs or libraries are required. Currently, UMSAP can process data obtained from proteolytic degradation experiments and generates graphical outputs allowing a straightforward interpretation of statistically relevant results.

RESULTS: UMSAP is used here to analyze the proteolytic degradation of glycerophosphoryl diester phosphodiesterase GlpQ by the protein quality control protease DegP. Mass spectrometry was used to monitor proteolysis over time in the absence and presence of a peptidic allosteric activator of DegP. The software's output clearly shows the increased proteolytic activity of DegP in the presence of the activating peptide, identifies statistically significant products of the proteolysis and offers valuable insights into substrate specificity.

CONCLUSIONS: Utilities for Mass Spectrometry Analysis of Proteins is an open-source software designed for efficient post-processing of large datasets obtained by MS analyses of proteins. In addition, the modular architecture of the software allows easy incorporation of new modules to analyze various experimental mass spectrometry setups.