An enterotype is a classification of living organisms based on the bacteriological composition of their

gut microbiota Gut microbiota, gut microbiome, or gut flora, are the microorganisms, including bacteria, archaea, fungi, and viruses that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut mi ...

. The discovery of three human enterotypes was announced in the April 2011 issue of ''

Nature Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are ...

'' by

Peer Bork Peer Bork (born 4 May 1963) is a German bioinformatician. He is Director of the European Molecular Biology Laboratory (EMBL) site in Heidelberg, in south-west Germany. Bork received his PhD in biochemistry in 1990 from the Leipzig Universit ...

and his associates. They found that enterotypes are not dictated by age, gender, body weight, or national divisions. There are indications that long-term diet influences enterotype. Type 1 is characterized by high levels of ''

Bacteroides ''Bacteroides'' is a genus of Gram-negative, obligate anaerobic bacteria. ''Bacteroides'' species are non endospore-forming bacilli, and may be either motile or nonmotile, depending on the species. The DNA base composition is 40–48% GC. Unus ...

'', type 2 has few ''Bacteroides'' but ''

Prevotella ''Prevotella'' is a genus of Gram-negative bacteria. ''Prevotella'' spp. are members of the oral, vaginal, and gut microbiota and are often recovered from anaerobic infections of the respiratory tract. These infections include aspiration pn ...

'' are common, and type 3 has high levels of ''

Ruminococcus ''Ruminococcus'' is a genus of bacteria in the class Clostridia. They are anaerobic, Gram-positive gut microbes. One or more species in this genus are found in significant numbers in the human gut microbiota. The type species is ''R. flavefacien ...

''. The value of classifying by enterotype has been challenged. In a study of gut bacteria of children in

Burkina Faso Burkina Faso (, ; , ff, 𞤄𞤵𞤪𞤳𞤭𞤲𞤢 𞤊𞤢𞤧𞤮, italic=no) is a landlocked country in West Africa with an area of , bordered by Mali to the northwest, Niger to the northeast, Benin to the southeast, Togo and Ghana t ...

(in Africa), ''Prevotella'' made up 53% of the gut bacteria, but were absent in age-matched European children. Studies also indicate that long-term diet is strongly associated with the

gut microbiome Gut microbiota, gut microbiome, or gut flora, are the microorganisms, including bacteria, archaea, fungi, and viruses that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the ...

composition—those who eat plenty of protein and animal fats typical of Western diet have predominantly ''Bacteroides'' bacteria, while for those who consume more carbohydrates, especially fibre, the ''Prevotella'' species dominate.

Chimpanzee The chimpanzee (''Pan troglodytes''), also known as simply the chimp, is a species of great ape native to the forest and savannah of tropical Africa. It has four confirmed subspecies and a fifth proposed subspecies. When its close relative t ...

s have enterotypes that are compositionally analogous to those found in humans. Using longitudinal samples, researchers found that the enterotype of individual chimpanzees varied over time.

References

Bacteriology Gut flora {{Microbiology-stub