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Automated postprocessing of electrospray LC/MS data for profiling protein expression in bacteria.

Tracie L Williams·Peter Leopold·Steven Musser
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Abstract

We describe an integrated approach for automating protein analysis of bacterial cell extracts. The method uses electrospray LC/MS to generate chromatographic profiles of proteins present in an extract, along with a software program that automates the data analysis. The software program, Retana, automates the sequential summing, centroiding, and deconvolution of multiply charged proteins present in consecutive scans of the LC/MS analysis. This procedure generates a concise, single spectrum of proteins present in the extract, along with their retention time and relative abundance. A comparison of the method with "whole cell" MALDI analysis demonstrates improved mass resolution and mass accuracy, along with the appearance of a greater number of proteins. Additionally, it is possible to compare protein expression among strains of bacteria by normalizing the relative abundance of similar proteins in each analysis.

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AutomationBacterial ProteinsChromatography, High Pressure LiquidData Interpretation, StatisticalProtein Processing, Post-TranslationalSpectrometry, Mass, Electrospray IonizationVibrio parahaemolyticusJournal Article

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Tracie L Williams, Peter Leopold, Steven Musser. 2002-11-15. Automated postprocessing of electrospray LC/MS data for profiling protein expression in bacteria.. https://doi.org/10.1021/ac0258958

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