|Simmons, Ibn Abdul|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/28/2009
Publication Date: 10/19/2009
Citation: Seal, B.S., Simmons, I.M., Donovan, D.M., Siragusa, G. 2009. BACTERIOPHAGES OF THE FAMILY SIPHOVIRIDAE CONTAIN AMIDASE ENZYMES THAT LYSE CLOSTRIDIUM PERFRINGENS. Meeting Abstract. Interpretive Summary:
Technical Abstract: In chickens Clostridium perfringens (Cp) is the etiologic agent of necrotic enteritis and causes gas gangrene along with being the third leading cause of bacterial food-borne gastroenteritis in humans. While the disease in poultry can be controlled by antibiotics, there is increasing pressure to ban antimicrobial growth promoters (AGP) in animal feed. Bans of AGP’s have yielded an increased incidence of Cp-associated necrotic enteritis in poultry which could potentially threaten human health. Consequently, screening of bacteriophages lytic for Cp was performed utilizing filtered samples obtained from poultry intestinal material, soil, sewage and poultry processing drainage in the southeastern USA. Bacteriophages had icosohedral heads with approximate 100 nm tails characteristic of the Siphoviridae family in the order Caudovirales and DNA genomes of approximately 40kb. Interestingly each one of the phages had host ranges restricted to specific Cp isolates. Two putative lytic enzyme genes from phiCP39O and phiCP26F were cloned, expressed in E. coli and the proteins purified to homogeneity. The actual Edman degradation/mass spectrometry and predicted amino acid sequences of the two recombinant proteins were homologous to amidases. The phage amidases were identical at the C-terminus (cell-wall binding domain), but only 55 per cent similar to each other at their N-terminal catalytic domain. Both recombinant lytic enzymes were able to lyse parental phage host strains of Cp as well as other Cp isolates assayed but not other clostridial species. Phage host-range specificity supports the use of phage lytic proteins rather than use of whole-phage preparations to control disease-causing bacteria.