Home  |  Top News  |  Most Popular  |  Video  |  Multimedia  |  News Feeds  |  Feedback
  Medicine  |  Nature & Earth  |  Biology  |  Technology & Engineering  |  Space & Planetary  |  Psychology  |  Physics & Chemistry  |  Economics  |  Archaeology
Top > Biology > Beneficial Microbes Are 'Selected And… >
Beneficial Microbes Are 'Selected And Nurtured' in the Human Gut

Published: November 21, 2012.
By Public Library of Science
http://www.plos.org

Animals, including humans, actively select the gut microbes that are the best partners and nurture them with nutritious secretions, suggests a new study led by Oxford University, and published November 20 in the open-access journal PLOS Biology.

The Oxford team created an evolutionary computer model of interactions between gut microbes and the lining (the host epithelial cell layer) of the animal gut. The model shows that beneficial microbes that are slow-growing are rapidly lost, and need to be helped by host secretions, such as specific nutrients, that favour the beneficial microbes over harmful ones.

The work also shows that the cost of such selectivity is low: the host only needs to use a very small amount of secretions to retain beneficial microbes that would otherwise have been lost.

"The cells of our bodies are greatly outnumbered by the microbes that live on us and, in particular, in our gut," said Professor Kevin Foster of Oxford University's Department of Zoology, an author of the new paper. "We know that many gut microbes are highly beneficial to us, protecting us from pathogens and helping us with digestion, but quite how such a beneficial mutual relationship evolved, and how it is maintained, has been something of a mystery."

"This research highlights the importance of growth-promoting substances in our ability to control the microbes that live inside us. It shows that nutrients are more powerful when released by the host epithelial cell layer than when coming from the food in the gut, and suggests that controlling our microbes is easier than was previously thought."

Jonas Schulter, also of Oxford University's Department of Zoology and first author of the paper, said: "The inside of our gut is rather like a war zone, with all kinds of microbes battling it out for survival and fighting over territory. Our study shows that hosts only have to secrete a small quantity of substances that slightly favour beneficial microbes to tip the balance of this conflict: it means that favoured microbial species that would otherwise be lost don't just survive on the epithelial surface but expand, pushing any other strains out."

The team's simulations show that cells affected by host epithelial selection are least likely to be lost, and instead persist longest, causing 'selectivity amplification', whereby relatively tiny changes instituted by the host (in this case a very small amount of secretions of certain compounds) can be amplified to produce a large-scale effect.

The study may have wider implications than the human gut: selectivity amplification may occur in a range of other interactions between hosts and microbes, including the microbes that grow on the surface of corals and the roots of plants.


Show Reference »


Translate this page: Chinese French German Italian Japanese Korean Portuguese Russian Spanish


Disclaimer: The views expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the ScienceNewsline.

Most Popular - Biology »
HIPPOCAMPUS »
Neurons in the Brain Tune into Different Frequencies for Different Spatial Memory Tasks
DOMESTICATION »
The Story of Animal Domestication Retold
Many of our ideas about domestication derive from Charles Darwin, whose ideas in turn were strongly influenced by British animal-breeding practices during the 19th century, a period when landowners …
CROP »
Genetic Study Tackles Mystery of Slow Plant Domestications
"The Modern View of Domestication," a special feature of The Proceedings of the National Academy of Sciences (PNAS) published April 29, raises a number of startling questions about a …
SPERM »
In Sex-reversed Cave Insects, Females Have the Penises
EXPRESSION »
Trisomy 21: How an Extra Little Chromosome Throws the Entire Genome Off Balance
ScienceNewsline  |  About  |  Privacy Policy  |  Feedback  |  Mobile  |  Japanese
The selection and placement of stories are determined automatically by a computer program. All contents are copyright of their owners except U.S. Government works. U.S. Government works are assumed to be in the public domain unless otherwise noted. Everything else copyright ScienceNewsline.