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High-resolution functional proteomics by active-site peptide profiling.

ABSTRACT: Characterization and functional annotation of the large number of proteins predicted from genome sequencing projects poses a major scientific challenge. Whereas several proteomics techniques have been developed to quantify the abundance of proteins, these methods provide little information regarding protein function. Here, we present a gel-free platform that permits ultrasensitive, quantitative, and high-resolution analyses of protein activities in proteomes, including highly problematic samples such as undiluted plasma. We demonstrate the value of this platform for the discovery of both disease-related enzyme activities and specific inhibitors that target these proteins.

SUBMITTER: Okerberg ES

PROVIDER: S-EPMC555687 | biostudies-literature | 2005 Apr

REPOSITORIES: biostudies-literature

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High-resolution functional proteomics by active-site peptide profiling.

Okerberg Eric S ES Wu Jiangyue J Zhang Baohong B Samii Babak B Blackford Kelly K Winn David T DT Shreder Kevin R KR Burbaum Jonathan J JJ Patricelli Matthew P MP

Proceedings of the National Academy of Sciences of the United States of America 20050328 14

Characterization and functional annotation of the large number of proteins predicted from genome sequencing projects poses a major scientific challenge. Whereas several proteomics techniques have been developed to quantify the abundance of proteins, these methods provide little information regarding protein function. Here, we present a gel-free platform that permits ultrasensitive, quantitative, and high-resolution analyses of protein activities in proteomes, including highly problematic samples ...[more]

PMID: 15795380

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