Completion of the Campylobacter jejuni NCTC11168 genome sequence offers unr
ivalled opportunities to understand the molecular basis of virulence for th
is major pathogen. Among the many novel features revealed by the genome seq
uence are at least 24 hypervariable sequences mostly found in genes encodin
g surface structures. Variation in the length of poly G/C tracts in genes c
ontaining these hypervariable sequences is frequently found in other mucosa
l pathogens and is likely to play a key role in enabling C. jejuni to evade
the host immune response. Additionally, a novel capsule locus and three si
alylation pathways were identified which may be important in the pathogenes
is of both uncomplicated diarrhoeal disease and neurological sequelae of in
fection. The availability of the C. jejuni genome sequence data has coincid
ed with important technological advances in bioinformatics, gene mutagenesi
s, proteome analysis and DNA microarrays. A C. jejuni DNA microarray holds
great promise for transcriptome and comparative genome analysis. Given the
range of disease associated with C. jejuni infection, combined with the div
erse genotypic and phenotypic properties of clinical and environmental isol
ates, a Campylobacter DNA microarray will be particularly useful in determi
ning correlates of pathogenicity and in deciphering the epidemiology of the
organism. Post genome studies will liberate our understanding of C. jejuni
from the piecemeal study of individual genes or operons towards a comprehe
nsive analysis of the entire gene and protein complement. Armed with this w
ealth of new information, the opportunities to develop improved interventio
n strategies to reduce C. jejuni in the food chain will be enormous.