by Elio
TEM of 'Candidatus Midichloria mitochondrii' inside a mitochondrion. Courtesy of L. Sacchi, University of Pavia, Italy.
There is more to the bacterial invasion of mitochondria than we had known. Previously, we divulged that bacteria can be found within the mitochondria of certain Italian cockroaches, an unusual form of parasitism if there ever was one. Erin Banning of the Marine Biological Laboratory at Woods Hole told us of a paper from the University of Sydney (not available online in 2014) that points out similarities between this invasion and that of Bdellovibrio. In both cases the predator grows in the periplasm of the host "cell" – an unusual place for a parasite to grow. The title of the paper tells all: "A symbiont of the tick Ixodes ricinus invades and consumes mitochondria in a mode similar to that of the parasitic bacterium Bdellovibrio bacteriovorus." We already wondered if the Bdellovibrio-type mechanism is limited to bacterial predation of bacteria. Sure, mitochondria were once bacteria, but...
Thanks, Erin.