Global relative and absolute quantitation in microbial proteomics

Proteomic studies are designed to yield either qualitative information on proteins (identification, distribution, posttranslational modifications, interactions, structure and function) or quantitative information (abundance, distribution within different localizations, temporal changes in abundance due to synthesis and degradation or both). To this end these studies can draw upon a wide range of qualitative and quantitative gel-based and gel-free techniques. This review summarizes current proteomic workflows for global relative or absolute protein quantitation and their application in microbial physiology.

► Global quantitation studies are indispensable in microbial proteomics. ► Proteome studies reflect the status quo of the cells’ key components. ► Relative and absolute proteome studies rely on gel-based and gel- free techniques. ► Integration of data with other ‘omic techniques points out to systems biology approaches. ► Workflows applied achieving high coverage of proteome data are reviewed.