Classification of living organisms based on its gut microbiome
An enterotype is a classification of living organisms based on the bacteriological composition of their gut microbiota. The discovery of three human enterotypes was announced in the April 2011 issue of Nature by Peer Bork and his associates.[1] They found that enterotypes are not dictated by age, gender, body weight, or national divisions.[2] There are indications that long-term diet influences enterotype.[3] Type 1 is characterized by high levels of Bacteroides, type 2 has few Bacteroides but Prevotella are common, and type 3 has high levels of Ruminococcus.[1][4][5]
The value of classifying by enterotype has been challenged.[6][7]
In a study of gut bacteria of children in Burkina Faso (in Africa), Prevotella made up 53% of the gut bacteria, but were absent in age-matched European children.[8]
Studies also indicate that long-term diet is strongly associated with the gut microbiome 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.[9]
Chimpanzees 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.[10]
References
^ abZimmer, Carl (20 April 2011). "Bacteria Divide People Into 3 Types, Scientists Say". The New York Times. Retrieved 21 April 2011. a group of scientists now report just three distinct ecosystems in the guts of people they have studied.
^Arumugam M, Raes J, et al. (April 2011). "Enterotypes of the human gut microbiome". Nature. 473 (7346): 174–80. Bibcode:2011Natur.473..174.. doi:10.1038/nature09944. PMC3728647. PMID21508958. Our knowledge of species and functional composition of the human gut microbiome is rapidly increasing, but it is still based on very few cohorts and little is known about variation across the world. By combining 22 newly sequenced faecal metagenomes of individuals from four countries with previously published data sets, here we identify three robust clusters (referred to as enterotypes hereafter) that are not nation or continent specific.