The proto-mitochondrion is the ancestral bacterial endosymbiont from which all mitochondria are thought to be derived.
Phylogeny [edit]
The phylogenetic analyses of the few genes that are still encoded in the genomes of modern mitochondria suggest an alpha-proteobacterial origin for this endosymbiont. Although the order Rickettsiales has been proposed as the alpha-proteobacterial sister-group of mitochondria, there is no definitive evidence as to from which alpha-proteobacterial group the proto-mitochondrion emerged.
| Phylogeny of Rickettsiales |
|
|
| Robust phylogeny of Rickettsiales from Williams et al. (2007)[1] |
Metabolism [edit]
Toni Gabaldón and Martijn Huynen (2003) reconstructed the proteome and corresponding metabolism of the proto-mitochondrion by comparing extant alpha-proteobacterial and eukaryotic genomes. They concluded that this organism was an aerobic alpha-proteobacterium catabolyzing lipids, glycerol and other compounds provided by the host. At least 630 gene families derived from this organism can still be found in the 9 eukaryotic genomes analyzed in the study.[2]
References [edit]
