When I first got into blogging, I thought I could carve out my niche talking about the microbiome – that enormous ecosystem of trillions living inside and on every one of us. However, it’s become increasingly clear that writers far more skilled than I have also decided to tackle this weighty (2-5lbs on average) subject.
Take this new paper published yesterday in Nature, describing 3 different “enterotypes” – different ways of balancing that ecosystem. I saw it last night in my Nature RSS feed, and was hoping to tackle it today.
Our gut contains trillions of bacteria, known collectively as the microbiome. Their cells outnumber our own by ten to one. We are, to the closest approximation, thriving communities of bacteria encased in a human shell. No two people have quite the same collection – we differ slightly in the species we contain, and there can be hundreds jostling for space.
But this variation isn’t infinite. Previous studies have shown that once people reach adulthood, their microbiomes become remarkably stable. Even after the communities are rocked by antibiotic assaults, they rebound to their old selves, recruiting members in the same proportions as before. Now, Manimozhiyan Arumugam and Jeroen Raes from the European Molecular Biology Laboratory (EMBL) have found that these constraints go even further. There seem to be just three preferred ways of building a community of gut bacteria.
Whatever the cause of the different enterotypes, they may end up having discrete effects on people’s health. Gut microbes aid in food digestion and synthesize vitamins, using enzymes our own cells cannot make.
Dr. Bork and his colleagues have found that each of the types makes a unique balance of these enzymes. Enterotype 1 produces more enzymes for making vitamin B7 (also known as biotin), for example, and Enterotype 2 more enzymes for vitamin B1 (thiamine).
Part of me is jealous that they’re doing what I was planning to do and doing it better than I would have done. But most of me is grateful that these two are coving this incredibly exciting and fast moving field.