ROLE OF CAMPYLOBACTER-JEJUNI FLAGELLA AS COLONIZATION FACTORS FOR 3-DAY-OLD CHICKS - ANALYSIS WITH FLAGELLAR MUTANTS

Campylobacter jejuni, an important cause of human gastrointestinal inf ection, is a major food-borne pathogen in the United States and worldw ide. Since poultry becomes colonized and/or contaminated during the ea rly stages of production and is a major food-borne source for this org anism, we studied the role of C. jejuni flagella on the ability of the bacterium to colonize the chicken gastrointestinal tract. Three-day-o ld chicks were orally challenged with a motile wild-type strain of C. jejuni IN9 or with flagellar mutants created from IN9 by disrupting th e flagellin genes with a kanamycin resistance cassette by using shuttl e mutagenesis (A. Labigne-Roussel, P. Courcoux, and L. Tompkins, J. Ba cteriol. 170:1704-1708, 1988). One mutant, IN9-N3, lacked flagella and was nonmotile. The other, IN9-N7, produced a truncated flagellum and was partially motile. Three-day-old chicks were orally challenged with different doses of the wild-type strain and the two mutants. At chall enge doses ranging from 3.0 x 10(4) to 6.6 x 10(8) CFU per chick, only the fully motile, wild-type strain colonized the chick ceca. Our resu lts show that intact and motile flagella are important colonization fa ctors for C. jejuni in chicks.