Through analyzing over 1,000 human fecal samples, these scientists found that bacteria were using specific immunity genes to neutralize toxins and protect themselves, and any invaders that lacked the right genes were kicked out of the gut.
They had assumed that the immunity genes and harmful toxins had a 1:1 ratio—for every one toxin, there was an immunity gene to help knock it out. What was surprising, however, was that there were tons more immunity genes than toxins in these fecal samples. They also saw how immunity genes were jumping from bacteria to bacteria, and in turn, the bacteria were using these immunity genes in order to become resistant to toxins and survive in the gut.
Because they studied over 1,000 fecal samples, these researchers were able to discover that different samples had different combinations of toxins and immunity genes. “So what it takes to survive in one person’s microbiome might not be the same in another person’s microbiome,” co-author Joseph Mougous, Ph.D., says.
It makes total sense: We already knew that what works for one person’s gut may not work for another’s (while intermittent fasting may give you astounding results, it might not be the best option for a friend!), and now we know why at the cellular level.