Query: NC_010830:193379 Candidatus Amoebophilus asiaticus 5a2, complete genome
Lineage: Amoebophilus asiaticus; Amoebophilus; Amoebophilaceae; Cytophagales; Bacteroidetes; Bacteria
General Information: Candidatus Amoebophilus asiaticus 5a2 is an obligate endosymbiont found in Acanthamoeba sp. TUMSJ-321. This organism is a member of the highly diverse bacterial phylum Bacteroidetes which includes the endosymbiont lineages represented by the sister taxa Candidatus A. asiaticus and Candidatus Cardinium hertigii, a symbiont of arthropods.
Subject: NC_015662:385461 Buchnera aphidicola (Cinara tujafilina) chromosome, complete
Lineage: Buchnera aphidicola; Buchnera; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria
General Information: It is believed that the Buchnera provide the essential nutrients the host lacks. Besides a nutritional co-dependence, due to a co-existence of millions of years, Buchnera have lost the ability to produce cell surface components such as lipopolysaccharides. This makes for an obligate endosymbiont relationship between host and Buchnera. Buchnera are prokaryotic cells which belong to the gamma-Proteobacteria, closely related to the Enterobacteriaceae family. Phylogenetic studies using 16S rRNA indicate that the symbiotic relationship was established around 200-250 million years ago. Since Buchnera are closely related to Escherichia coli and Haemophilus influenzae, comparative genomic studies can shed light on the evolutionary mechanisms of intracellular endosymbiosis as well as the different underlying molecular basis between organisms with parasitic behavior and symbionts.