REDBIO México 2010

Folio: 431
Tipo de presentación: Oral
Tema: Otro
Este trabajo se presentará en "Presentaciones Libres 14: Ómicas" el Miercoles dentro del horario 16:40 a 18:40

PEPTIDE FRACTIONATION FOR PROTEOMIC STUDIES

Lázaro Betancourt, Aniel Sánchez, Jeovanis Gil, Jorge Fernández-de-Cossío, Yassel Ramos, Félix Alvarez, Yasset Pérez, Yordanka Masforrol, Osvaldo Reyes, Vladimir Besada, Luis Javier González and Gabriel Padrón.
Centro de Ingeniería Genética y Biotecnología

RESUMEN (ABSTRACT)
"Proteomics has evolved towards shotgun strategies based on multidimensional chromatography and mass spectrometry analysis (LC-MS/MS) of peptide mixtures derived from cell extracts. However, very complex peptide mixtures are obtained, limiting the detection of many of those peptides and the identification of several proteins, particularly the low abundance proteins. Fractionation at protein or peptide level has been found to enhance protein identification. We have developed some methods for improving protein identification. Three of these methods (SCAPE) were developed for selective isolation of peptides based on derivatization of _ and _ amino groups to modulate the presence of positive charges at acid pH and further separation by cation exchange chromatography or affinity chromatography. In addition we have developed a procedure for peptide fractionation by SDS-free polyacrylamide gel electrophoresis. Complex protein extracts separated by SDS-PAGE are trypsin digested and peptides further fractionated by SDS free-PAGE. Peptides migrate to the anode electrode in accordance with the charge-molecular mass ratio. Identified proteins increased 2.5 fold. The use of SDS for protein fractionation allows analysis of highly hydrophobic proteins and minimal protein loses. Finally, we are using combinatorial peptide libraries for equalization of peptide mixture in order to decrease the wide dynamic concentration range and to improve the detection and identification of low-abundance proteins."