Submitted to: Research in Veterinary Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/30/2011
Publication Date: 6/15/2011
Citation: Lee, K., Lillehoj, H.S., Li, G., Park, M., Jang, S., Lillehoj, E.P., Jeong, W., Jeong, H., An, D. 2011. Identification and cloning of two immunogenic Clostridium perfringens proteins, elongation factor Tu (EF-Tu) and pyruvate:ferredoxin oxidoreductase (PFO) of C. perfringens. Research in Veterinary Science. 91:e80-86. Interpretive Summary: Gangrenous dermatitis (GD) and necrotic enteritis (NE) are among the most important enteric and skin-associated poultry diseases in the U.S. NE is caused by Clostridium perfringens type A, a Gram-positive, anaerobic, spore-forming, rod-shaped bacterium whereas GD is primarily associated with infection by C. perfringens type A or C. septicum with underlying predisposing factors. Although there is increasing concerns about these infections, very limited information on these pathogens limits our ability to devise effective prevention strategies. This study reports cloning and biochemical characterization of novel C. perfringens proteins which are immunogenic in chickens. ARS scientists discovered two antigenic C. perfringens proteins, elongation factor Tu (EF-Tu) and pyruvate:ferredoxin oxidoreductase (PFO) and cloned genes for recombinant protein production. Using these recombinant proteins as target antigens in immunoassays, high serum antibody titers were observed in chickens with clinical signs of clostridial infections. The results of this study will enhance our ability to develop in vitro diagnostic kits to identify field chickens infected with GD and NE in commercial poultry.
Technical Abstract: Clostridium-related diseases such as gangrenous dermatitis (GD) and necrotic enteritis (NE) are increasingly emerging as major diseases in recent years with high economic loss around the world. In this report, we characterized two immunogenic Clostridium perfringens (CP) proteins (e.g., elongation factor Tu [EF-Tu] and pyruvate:ferredoxin oxidoreductase [PFO]) which were identified by chicken sera from birds with clinical sign of GD in a field clostridium outbreak. In addition to EF-Tu and PFO, we cloned two additional CP genes encoding virulent factors, e.g., a-toxin and NetB, which are important in the diagnosis of clostridial disease. All four CP genes were expressed, recombinant proteins purified and were used to detect antibodies in sera from birds with clinical signs of NE. The results showed that these four CP proteins are immunogenic and are recognized by immune serum from CP-infected, but not in normal chickens, implying their potential vaccine candidates against clostridial diseases.