Biomedical subjects

Christopher M Colangelo

Publications and source records attributed to Christopher M Colangelo.

3 recordsLinked to original sources

PubMed2006

Isotope-coded affinity tags for protein quantification.

An important goal in proteomics is to compare the relative amounts of different proteins in biological samples and to try to correlate these differences with changes in physiological state. The isotopecoded affinity tag technique pioneered in Aebersold's laboratory takes advantage of differential tagging of cysteine residues in proteins with stable isotopes to significantly reduce the complexity of peptide mixtures and increase the number of sequences that are identified in a single tandem mass spectrometry experiment. In this approach, two samples are isotopically labeled (one heavy, one light) through a reactive group that specifically binds to cysteine residues; the samples are combined, separated with chromatography, and analyzed by mass spectrometry. The results are then database searched and a list of hundreds of proteins and their heavy:light ratio is obtained.

Avidin↗

PubMed2005

YPED: a proteomics database for protein expression analysis.

We have developed the Yale Protein Expression Database (YPED) to address the storage, retrieval, and integrated analysis of proteomics data generated by Yale's Keck Protein Chemistry and Mass Spectrometry Facility. YPED is Web-accessible and currently handles sample requisition, result reporting and sample comparison for ICAT, DIGE and MUDPIT samples. Sample descriptions are compatible with the evolving MIAPE standards. Peptides and proteins identified using Sequest or Mascot are validated with the Trans-Proteomic Pipeline developed at the Institute of Systems Biology and data from the resulting XML file are stored in the database. Researchers can view, subset and download their data through a secure Web interface.

Databases, Protein↗

PubMedDate not supplied

A simple solid phase mass tagging approach for quantitative proteomics.

New mass-tagging reagents for quantitative proteomics measurements have been designed using solid phase peptide synthesis technology. The solid phase mass tags have been used to accurately measure the relative amounts of cysteine-containing peptides in model peptide mixtures as well as in mixtures of tryptic digests in the femtomol range. Measurements were made using both matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and online reversed-phase capillary liquid chromatography coupled through a nanoelectrospray interface to an ion trap mass spectrometer (capillary LC/ESI-MS). Results of mass-tagging experiments obtained from these two mass spectrometry techniques and their relative advantages and disadvantages for identification and quantitation of mass tagged peptides are compared. These reagents provide a simple, rapid and cost-effective alternative to currently available mass tagging technologies.

Chromatography, High Pressure Liquid↗