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Signature-tagged mutagenesisA method for simultaneously screening pools of bacteria that have transposon-generated mutations that is used to identify genes that are required for survival under the conditions specified by the investigator. Widely used to identify genes in bacterial pathogens that are required for virulence or colonization.
As a human pathogen, http://www.ncbi.nlm.nih.gov/sites/entrez?db=genomeprj&cmd=Retrieve&dopt=Overview&list_uids=12299
Web End =Campylobacter jejuni is an accidental tourist that has reservoirs in water and various animals13 (FIG. 1). In the developed world,
where waterborne infection is less likely, animals are the primary source of human infection and disease (termed campylobacteriosis). Frequently, and perhaps most commonly, disease arises after the consumption of chicken products that have been contaminated during processing. C. jejuni is considered to be a commensal organism of chickens and other avian species. Although the experimental infection of chickens with C. jejuni can lead to diarrhoea4,5, this is not typical, and it appears that the human response to C. jejuni infection is more symptomatic than that of the chicken. This situation is similar to that with the better-characterized pathogen enterohaemorrhagic http://www.ncbi.nlm.nih.gov/sites/entrez?db=genomeprj&cmd=Retrieve&dopt=Overview&list_uids=12319
Web End =Escherichia coli , which is a common colonizer of cattle and causes human disease through the ingestion of ground beef and other foods that have been contaminated by contact with cattle faeces. In both cases, control measures for human populations might be more successful if they were directed at reducing colonization of the natural host. Some potential control measures for Campylobacter infections are discussed in BOX 1.
C. jejuni belongs to the epsilon class of proteobacteria, in the order Campylobacteriales; this order includes two other genera, Helicobacter and Wolinella. Like C. jejuni, members of these genera have small genomes (1.62.0 megabases) and can establish long-term associations with their hosts, sometimes with pathogenic consequences. The genus Helicobacter includes the species http://www.ncbi.nlm.nih.gov/sites/entrez?db=genomeprj&cmd=Retrieve&dopt=Overview&list_uids=12321
Web End =Helicobacter pylori , which causes gastric ulcers and is clearly a pathogen, but which can be carried asymptomatically in humans for decades. The
genus Wolinella contains a single species, http://www.ncbi.nlm.nih.gov/sites/entrez?db=genomeprj&cmd=search&term=Wolinella succinogenes
Web End =Wolinella http://www.ncbi.nlm.nih.gov/sites/entrez?db=genomeprj&cmd=search&term=Wolinella succinogenes
Web End =succinogenes , which colonizes cattle as a commensal organism. Thus, these related organisms appear to be host-adapted and can establish and maintain their niches without generating a response in the host that is sufficient for clearance.
The basis for...