18O Labeling over a Coffee Break: A Rapid Strategy for Quantitative Proteomics

A robust method for quantitative high-throughput analysis of proteomes by 18O labeling.

MS-based quantitative proteomics plays an increasingly important role in biological and medical research and the development of these techniques remains one of the most important challenges in mass spectrometry. Numerous stable isotope labeling approaches have been proposed. However, and particularly in the case of (18)O-labeling, a standard protocol of general applicability is still lacking, a...

Proteolytic 18O labeling for comparative proteomics: evaluation of endoprotease Glu-C as the catalytic agent.

Recently, proteolytic 18O labeling has been demonstrated as a promising strategy for comparative proteomic studies (Yao, X.; Freas, A.; Ramirez, J.; Demirev, P. A.; Fenselau, C. Anal. Chem. 2001, 73, 2836-42). In this approach, protein mixtures are digested in parallel in H216O and H218O and the ratios of isotopically distinct peptide products are measured by mass spectrometry. In the initial r...

Mark Handcock 10 : 00 Coffee break Coffee break Coffee break 10 : 30

O18Quant: A Semiautomatic Strategy for Quantitative Analysis of High-Resolution 16O/18O Labeled Data

Proteolytic (18)O-labeling has been widely used in quantitative proteomics since it can uniformly label all peptides from different kinds of proteins. There have been multiple algorithms and tools developed over the last few years to analyze high-resolution proteolytic (16)O/(18)O labeled mass spectra. We have developed a software package, O18Quant, which addresses two major issues in the previ...

In vivo isotopic labeling of proteins for quantitative proteomics.

INTRODUCTIONStable isotope coding strategies are of immense value in determining protein concentration changes in cells and tissues triggered by regulatory stimuli (e.g., drugs and toxins) and disease (e.g., caused by mutational changes). Recognizing and identifying the small number of proteins whose expression levels differ as a consequence of disease or external stimuli are complicated by the...