Abstract
During the hundreds of thousands of years that bacteria have co-existed with humans, they have developed highly specialised skills to maintain stable niches in the gastrointestinal tract. To achieve this they act in concert with their hosts to create a fully integrated ecosystem and facilitate the process by modifying host gene expression and function so that habitats are shaped according to the needs and capabilities of the resident flora. This has a profound influence on the human host, and we are dependent on a functional intestinal microflora for our health. By deciphering the strategies employed by the intestinal microflora to create mutualistic relationships with its host we will gain entirely new insights into the shaping and maintenance of human physiology. The combination of genetically defined model hosts and microorganisms, gnotobiology providing a controlled environment, and high resolution molecular techniques will be important tools in this quest. These insights will provide a more accurate understanding of both functionality as well as of the pathogenesis of a wide array of diseases. In addition, it will open up new opportunities for treatment and prevention of disease.
