PROTEIN IDENTIFICATION BY MASS SPECTROMETRY

Protein Identification Service

Currently, we offer protein identification by tandem mass spectrometry. We utilize nano-LC/MS/MS technique, which is one of the most sensitive and reliable methods available now. It allows identification of proteins at low fmol levels and enables identification of numerous proteins in protein mixtures.

Protein identification in gel slices

Protein identification in gel slices includes sample preparation, digestion, peptide extraction, nano-LC/MS/MS data acquisition, and data analysis (including automated NIH database search by SEQUEST software and data quality control by a human expert). The results of the analysis are e-mailed to the customer in Excel format.

New service: identification of proteins in dry archived gels

With the development of new analytical techniques, older research data could be revisited and revised, resulting in new discoveries achieved by a very cost-effective means.

It has been shown that decade-old gels can be used for protein identification by mass spectrometry:

1. H. Matsumoto, N. Komori, Protein identification on two-dimensional gels archived nearly two decades ago by in-gel digestion and matrix-assisted laser desorption ionization time-of-flight mass spectrometry, Anal. Biochem. 270 (1999) 176-179.

2. A. Shevchenko, A. Loboda, W. Ens, B. Schraven, K.G. Standing, Archived polyacrylamide gels as a resource for proteome characterization by mass spectrometry, Electrophoresis 22 (2001) 1194-1203.

Recognizing that old protein preps stored in laboratory journals in the form of dried SDS-PAGE gels could be a source of new information, we developed proprietary techniques for efficient extraction and analysis of material from archived gels. We are pleased to offer this new service to our customers.

One area in which this technique might yield new discoveries is the identification of new interaction partners in protein complexes purified from endogenous sources. An example of such findings was published recently and can be viewed here.

We accept protein slices cut out from archived gels that were stored at room temperature for up to 20 years. Gels dried on filter paper or between cellophane sheets are both acceptable.

This service is listed in the catalog as ID-02 and ID-02a.