From Wikipedia, the free encyclopedia
For other uses, see Microbiota (disambiguation).
A microbiota is "the ecological community of commensal, symbiotic and pathogenicmicroorganisms that literally share our body space". Joshua Lederberg coined the term, emphasising the importance of microorganisms inhabiting the human body in health and disease. Many scientific articles distinguish microbiome and microbiota to describe either the collective genomes of the microorganisms that reside in an environmental niche or the microorganisms themselves, respectively. However, by the original definitions these terms are largely synonymous.
The human body contains over 10 times more microbial cells than human cells, although the entire microbiome only accounts for about for 1-3% total body mass, with some weight-estimates ranging as high as 3 pounds (approximately 48 ounces or 1,400 grams). Research into the role that microbiota in the gut might play in the human immune system started in the late 1990s. The microbiome of the gut has been characterised as a "forgotten organ", and the possibility has been raised that "the mammalian immune system, which seems to be designed to control microorganisms, is in fact controlled by microorganisms". The human microbiome may have a role in auto-immune diseases like diabetes, rheumatoid arthritis,muscular dystrophy, multiple sclerosis, fibromyalgia, and perhaps some cancers. A poor mix of microbes in the gut may also aggravate common obesity. Since some of the microbes in the human body can modify the production of neurotransmitters known to occur in the brain, it[clarification needed] may also relieve schizophrenia, depression, bipolar disorder and other neuro-chemical imbalances.
The microbes being discussed are generally non-pathogenic (they do not cause disease unless they grow abnormally); they exist in harmony and symbiotically with their hosts. Moreover, it has been stated that microbiome and host emerged as a unity along evolution by a process of integration.