Concentration of microbes in human gut

Range 10^11 - 10^12 microbes/ml
Organism Microbes
Reference Mahowald MA et al., Characterizing a model human gut microbiota composed of members of its two dominant bacterial phyla. Proc Natl Acad Sci U S A. 2009 Apr 7 106(14):5859-64. doi: 10.1073/pnas.0901529106. p.5859 right column 3rd paragraphPubMed ID19321416
Comments p.5859 right column 3rd paragraph: "These observations support the notion that gut microbes may live at the intersection of 2 forms of selective pressure: bottom-up selection, where fierce competition between members of a community that approaches a population density of 10^11 to 10^12 organisms per milliliter of colonic contents drives phylotypes to assume distinct functional roles (niches): and top-down selection, where the host selects for functional redundancy to ensure against the failure of bioreactor functions that could prove highly deleterious (refs 9, 10)."
Entered by Uri M
ID 112466