On the bacterial ancestry of mitochondria: new insights with triangulated approaches

ABSTRACT We breathe at the molecular level when mitochondria in our cells consume oxygen to extract energy from nutrients. Mitochondria are characteristic cellular organelles that derive from aerobic bacteria similar to some of those thriving in the oceans nowadays. These organelles carry out most metabolic pathways in eukaryotic cells. The precise bacterial origin of mitochondria and, consequently, the metabolic ancestry of our cells remains controversial - despite the vast genomic information that is now available. Here we triangulate across multiple phylogenomic and molecular approaches to pinpoint the most likely living relatives of the ancestral bacteria from which mitochondria originated.