There's been a flood of information about microbes lately that I haven't fully digested. The study briefly mentioned in the earlier post Parfait, and other work that it links to note the prevalence and implications of atmospheric bacteria and fungi. The little buggers are everywhere and we breathe them, sometimes to our detriment.

We aren't actually independent of that pervasive microbial world. They are under us, around us and in us.

Trillions of microbes make their home in the gut, where they help to break down and extract energy and nutrients from the food we eat. Yet, scientists have understood little about how this distinctive mix of microbes varies from one individual to the next.

Now, by cataloging the microbial species in the guts of lean and obese, identical and fraternal female twins and their mothers using a new generation of powerful DNA sequencers, researchers at Washington University School of Medicine in St. Louis have discovered that each individual carries a unique collection of bacteria, although the communities are more similar among family members. . .

. . . when the study's lead author Peter Turnbaugh, a graduate student working in Gordon's lab, sequenced the microbial community DNA, or microbiome, of a subset of obese and lean twin pairs, he found that obese individuals had an increased representation of nearly 300 bacterial genes, many of which are devoted to extracting calories from food and processing nutrients. This new evidence supports Gordon's earlier research in mice that established a link between obesity and the efficiency of energy harvest from the diet by gut bacteria. . .

"It appears that we acquire an enormous number of genes - in the form of our microbial genes - from our early environment. These microbial genes, together with our human genes, form our 'metagenome."

I find it useful to view humans and their microbial symbionts as a metaorganism with a metagenome. It's interesting to consider that chubby folks may be so because they have better tummy bugs that do a better job of digesting the food they eat, and that they seem to get these bugs from their childhood environment - their mothers are a big part of that.

Managing those gut microbes seems like it could be useful. We think about such things in livestock management. For example, there has been research about inoculating ruminants with bacteria that produce less methane and glean more energy from forage. We also think about managing soil microbes, such as in the common practice of inoculating soil with rhizobia to enhance nitrogen fixation, and some are now using fungal inoculants such as the various strains of mycorrhizae to enhance nutrient transport and carbon sequestration (glomalin).

It sometimes seems to me that we have a confused view of ourselves as a dominant life form. Maybe we are livestock being used by microbes to achieve their slow, inscrutable purposes. OK, that's weird. But still. . .