A key sentence in Katherine Lemon et al.’s “Microbiota-Targeted Therapies: An Ecological Perspective” jumped out at me.
Lemon et al. write:
“The host may be indifferent to which species are present, but the community’s ability to liberate nutrients from the diet and resist pathogen invasion are vital.”
They write that which members of the gut microbiota are present might be less important than their function. Lemon et al. certainly hit the nail on the head by identifying the fitness effects of the microbiota: their ability to provide energy to the host and to prevent invasive infection.
A next step in pursuing an ecological approach to the gut microbiome might be to actually measure the fitness consequences of changed microbiota in the lab and in humans.
Joe Alcock MD