Comparative analysis of extractable proteins from Clostridium perfringens type A and type C strains showing varying degree of virulence.

The prevailing scenario of bioterrorism warrants development of medical countermeasures with expanded coverage of select agents. Clostridium perfringens is a pathogen of medical, veterinary and military importance, and has been listed as Validated Biological Agent. We employed 2DE-MS approach to identify a total of 134 unique proteins (529 protein spot features) from the extractable proteome of four type A and type C strains. Proteins showing altered expression under host-simulated conditions from virulent type A strain (ATCC13124) were also elucidated. Significant among the differentially expressed proteins were elongation factor, molecular chaperones, ribosomal proteins, carbamoyl phosphate synthase, clpB protein, choloylglycine hydrolase, phosphopyruvate hydratase, and trigger factor. Predictive elucidation, of putative virulence associated proteins and sequence conservation pattern of selected candidates, was carried out using homologous proteins from other bacterial select agents to screen for the commonality of putative antigenic determinants. Pathogens (17 select agents) were observed to form three discrete clusters; composition of I and II being consistent in most of the phylogenetic reconstructions. This work provides a basis for further validation of putative candidate proteins as prophylactic agents and for their ability to provide protection against clusters of pathogenic select bacterial agents; aimed at mitigating the shadows of biothreat.