Query: NC_016930:943000 Rickettsia philipii str. 364D chromosome, complete genome
Lineage: Rickettsia philipii; Rickettsia; Rickettsiaceae; Rickettsiales; Proteobacteria; Bacteria
General Information: Rickettsiae are obligate intracellular Gram-negative bacteria mostly found in arthropods, some of which cause mild to severe diseases in humans. Spotted fever group rickettsiae (SFGR) cause disease in humans. R .philippi strain 364D, an SFGR, was isolated in 1966 from Dermacentor occidentalis ticks collected in Ventura county, California, and since then 364D has been detected in up to 11% of D. occidentalis from 8 California counties. It has now been recognized as causing eschar-associated illness.
Subject: NC_008044:1401814 Silicibacter sp. TM1040, complete genome
Lineage: Ruegeria; Ruegeria; Rhodobacteraceae; Rhodobacterales; Proteobacteria; Bacteria
General Information: This strain was isolated from a culture of the dinoflagellate Pfiesteria piscicida CCMP1830 which has been implicated in many large scale algal blooms resulting in increased mortality in fish. The bacteria are attached to the surface of the dinoflagellate and in some ways allow the dinoflagellate to grow as those lacking the bacteria die off. The bacterium also chemotaxes towards the dinoflagellate product DMSP (dimethylsulfoniopropionate) and metabolizes it. DMSP is a major source of sulfur in marine ecosystems and plays a role in the sulfur biogeochemical cycle. The implication is a tight association between these important dinoflagellates and this marine bacterium.