Encapsulin-associated ferritin proteins form metal-dependent decamers that are active as ferroxidase enzymes, but require encapsulation to form an iron store.
Diverse sophisticated phylogenetic analyses update the phylogeny of the Alphaproteobacteria and show that the parasitic Holosporales is a derived group within the Rhodospirillales order which comprises primarily free-living alphaproteobacteria.
A number of microbial eukaryotes have adapted to low oxygen conditions by acquiring a gene that allows their mitochondrial electron transport chain to continue to function when oxygen is scarce.