The Journal of Medical Microbiology, Vol 38, Issue 4 293-300, Copyright © 1993 by Society for General Microbiology
Characteristics of an avirulent Campylobacter jejuni strain and its virulence-enhanced variants
L. H. Field, J. L. Underwood, S. M. Payne and L. J. Berry
Department of Microbiology, University of Texas, Austin 78712-1095.
The virulence of Campylobacter jejuni for 11-day-old chick embryos is
associated with the ability to invade the chorio-allantoic membrane, to
resist phagocytosis and to survive and proliferate in vivo. The
pathogenicity of a well characterised avirulent C. jejuni strain was
enhanced by passaging it intravenously and chorio-allantoically through
chick embryos. The resulting isogenic variants had greatly increased
ability to survive in vivo. In this study, the morphological and
cell-surface characteristics of the avirulent parental strain were compared
with those of the more virulent variants to determine whether pathogenicity
was associated with one or more cell-surface constituents. Changes
associated with the increased virulence of the two variants included
alterations in cultural and cellular morphology, loss of flagella,
expression of a new outer-membrane protein, alterations in cell-surface
carbohydrates and decreases in cell-surface hydrophobicity.
