Reference map of soluble proteins from Salmonella enterica serovar Enteritidis by two-dimensional electrophoresis.

Protein identification by peptide mass fingerprinting using matrix-assisted laser desorption ionization time of fight (MALDI-TOF) mass spectrometry (MS) can analyze unambiguously identity of the spots from a 2-dimensional electrophoresis (2-DE) gel. This study developed a technique for 2-DE of Salmonella enterica serovar Enteritidis (S. enteritidis) by improving the dissolution conditions by 2-DE using a pH 4 - 7 immobilized pH gradient (IPG) strip. This report examines the protein components from the patterns of the S. enteritidis protein. The most abundant protein displayed a great number of clusters within the pH 4.5 - 7 range with a molecular mass ranging from 35-80 kDa. Some of these spots were identified as metabolic related enzymes. The protein fraction was also analyzed using an immobilized pH gradient strip. Different proteins were identified on the spot according to the elongation factors. In addition, this study showed that the 2-DE analysis of S. enteritidis provides useful information regarding the S. enteritidis proteome, and this approach might provide a strategy for identifying bacterial proteins using a proteome technology.