Image of the Day: Gut Bomb

Microbial species living in a fruit fly gut interact with one another—and influence the insect’s health and longevity in the process.

Catherine Offord
Dec 10, 2018
Lactobacillus (red) and Acetobacter (green) bacteria colonize a fruit fly gut (cell nuclei in blue).

Like humans, fruit flies have a community of microbial species living in their guts. Now, a team led by US researchers has shown that interactions between these species influence fruit fly fecundity, longevity, and other physiological factors, lending support to the idea that microbial interactions may be an important driver of animal health.

Using the five species most commonly found in Drosophila melanogaster, the team inoculated germ-free flies with each of the 32 possible combinations of those species and found that effects varied with the diversity and composition of the microbiome. In particular, interactions between species in the microbiome appeared to mediate whether flies were more likely to have a short lifespan and produce lots of offspring, or to have a long lifespan but produce relatively few offspring.

The findings suggest “that if we want to understand how the microbiome impacts our health, we need to develop a predictive understanding of how combinations of bacteria affect the host, not just the individual species,” study coauthor Will Ludington of the Carnegie Institution for Science says in a statement.

A.L. Gould et al., “Microbiome interactions shape host fitness,” PNAS, doi:10.1073/pnas.1809349115, 2018.