ABSTRACT
The gastrointestinal tract contains a diverse microbial community, which is predominantly bacterial and which is referred to as the gut microbiota. Over the last decade, the microbial composition of the gut has been the subject of increasingly intense research, much due to its demonstrated impact upon various health conditions. The Human Microbiome Project (HMP), MetaHIT (Metagenome of Human Intestinal Tract) and the smaller ELDERMET project, as well as numerous labs around the world (Table 1), have taken advantage of new high-throughput technologies to thoroughly characterise the human microbiome from multiple body sites at every stage of life. A number of these projects employed whole-community shotgun sequencing to study the gene content of the microbial populations. Through these studies, it has become apparent that these microorganisms are not just passive residents of the gut, but carry out a range of biological functions that are important in the nutrition and well-being of the individual.
