|Siragusa, Gregory -|
|Wise, Mark -|
|Neumann, Anthony -|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: March 1, 2011
Publication Date: May 21, 2011
Citation: Siragusa, G.R., Wise, M., Neumann, A., Oakley, B., Seal, B.S. 2011. Evidence of chitinase activity within necrotic enteritis-associated subtypes of Clostridium perfringens. Meeting Abstract. Volume: III Page:1493. Technical Abstract: C. perfringens (Cp) is associated with the necrotic gastrointestinal condition known as necrotic enteritis (NE) in the chicken. rep-PCR subtyping identified subtypes of Cp from the gastrointestinal tracts of broiler chickens afflicted with NE that were distinguished from strains from environmental, darkling beetles or healthy birds. The rep-PCR patterns showed a single very dominant rep-PCR amplicon associated with the diseased source. The homologous bands derived from the rep-PCR gel pattern of strains which were derived from an NE bird, healthy bird, and darkling beetle larva were excised and sequenced. Based on sequence analysis, evidence of a chitinase gene was linked to the necrotic-associated isolate but not the healthy bird derived or insect derived Cp isolates. Subsequently several (n=24) Cp isolates were assayed for endochitinase (chtiotriase), and exochitinase (chitobiosidase and ß-N-acetylglucosamidase) activities using a fluorescence substrate assay after growth in a non-inducing medium. Cp strains derived from the gastrointestinal tracts of NE birds expressed significantly higher levels of ß-N-acetylglucosamidase, and chitobiosidase compared to isolates not associated with NE. Endochitinase activity was not detected or was at a very low level in all isolates examined. To our knowledge this is the first report of chitin degrading enzyme activity within the Clostridium perfringens taxon. While autolytic enzyme activities similar to endo-chitinase substrates in Cp have been reported, we observed no or very low levels of endochitinase from any strain tested. At this point, any association of exochitinase activity and Cp pathogenicity in the fowl is purely founded on the rep-PCR derived pattern associations.