MOLECULAR CHARACTERIZATION AND GASTROINTESTINAL TRACT ECOLOGY OF COMMENSAL HUMAN FOOD-BORNE BACTERIAL PATHOGENS IN THE CHICKEN
Location: Poultry Microbiological Safety Research
Title: Characterization of a Differentially Translated Protein, OMP85, from Two Campylobacter jejuni Isolates with Different Colonization Potentials in Broiler Chickens
Submitted to: Campylobacter Helicobacter and Related Organisms International Workshop
Publication Type: Abstract Only
Publication Acceptance Date: June 8, 2007
Publication Date: September 4, 2007
Citation: Hiett, K.L., Kuntz, R.L., Seal, B.S. 2007. Characterization of a Differentially Translated Protein, OMP85, from Two Campylobacter jejuni Isolates with Different Colonization Potentials in Broiler Chickens. Campylobacter Helicobacter and Related Organisms International Workshop.
Campylobacter spp., considered a leading bacterial etiology of acute gastroenteritis in humans, is commonly associated with poultry. However, the factors involved in colonization of poultry with Campylobacter spp. remain unclear. Determination of colonization-associated factors should facilitate our understanding of Campylobacter spp. contamination of poultry. Therefore, comparative 2-Dimensional gel analyses between C. jejuni isolate 11168(GS), a poor colonizer of chickens, and isolate A74/C, a robust colonizer of chickens were conducted. Proteomic analyses revealed differential translation of several protein products; one protein in particular was subsequently identified as OMP85. The ubiquity of the Omp85 family in diverse pathogenic bacteria, coupled with their fundamental role in outer membrane assembly prompted further investigation of this protein. A library of twenty C. jejuni isolates originally recovered from diverse spatial and temporal sources were surveyed for omp85. Sequence data has been completed (2220 bp) for two C. jejuni isolates, while partial sequence data (1241/2220 base pairs) has been obtained for the additional eighteen isolates. Alignment of partial nucleotide sequence data demonstrated high similarity of the omp85 gene among C. jejuni isolates (98.4%). Additionally, nucleic acid hybridization analysis was performed with a library of Campylobacter species using the omp85 gene as a probe. Only two of the ten species tested, C. jejuni and C. mucosalis, demonstrated hybridization to the omp85 gene probe. This data demonstrates 1) the high similarity of omp85 nucleotide sequences among C. jejuni isolates, 2) the high antigenic index of the translated OMP85 protein, and 3) using both nucleotide sequence analysis (blastn) and amino acid similarity analysis (blastX) that omp85 sequence is unique to Campylobacter spp. relative to other poultry associated bacteria. Identification of different genes potentially involved in colonization of Campylobacter spp. in poultry will facilitate the development of targeted intervention strategies, thereby allowing the delivery of a safer product to consumers.