Comparative proteomic analysis on Salmonella Gallinarum and Salmonella Enteritidis exploring proteins that may incorporate host adaptation in poultry

Comparative proteomics analysis of the cytosolic proteins of Salmonella Gallinarum (SG) and Salmonella Enteritidis (SE) isolated from poultry was performed. The constantly detected spots of serovar SG with concomitant absence in SE serovar as well as those markedly over expressed in serovar SE were selected for MALDI-TOF-MS identification. The NCBI-matched proteins that show overregulation were then further confirmed on the mRNA level by quantitative real time PCR. Identified proteins were representing diverse functional activities including energy production, metabolism, and nucleic acid synthesis. Interestingly, some recognized proteins have some relevance to bacterial virulence e.g. Salmonella pathogenicity island 1 effector protein, T-cell inhibitor protein, response regulator protein, paratose synthetase protein (RfbS) and heat shock protein 90. The study revealed the presence of some proteins of unknown function, which raise the speculation for their importance in either host adaptation or pathogenicity among SG serovars.