Query: 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.
Subject: NC_004547:843475 Erwinia carotovora subsp. atroseptica SCRI1043, complete genome
Lineage: Pectobacterium atrosepticum; Pectobacterium; Enterobacteriaceae; Enterobacteriales; Proteobacteria; Bacteria
General Information: This strain (ATCC BAA-672) is a virulent blackleg isolated from the stem of a potato plant. Causative agent for blackleg and soft rot disease in potatoes. Formerly Erwinia, these organisms are plant-specific pathogens that invade the vascular systems of plants. Both Pectobacterium chrysanthemia and Pectobacterium carotovora cause soft-rot diseases of various plant hosts through degradation of the plant cell walls. Pectobacterium colonize the intercellular spaces of plant cells and deliver potent effector molecules (Avr - avirulence) through a type III secretion system (Hrp - hypersensitive response and pathogenicity). Avr proteins control host-bacterium interactions, including host range. Expression of the plant cell-wall-degrading enzymes is controlled through a quorum-sensing mechanism that quantifies the number of Pectobacterium bacteria through measurement of the concentration of small molecules (acyl homoserine lactones) produced by Pectobacterium. Pectobacterium atrosepticum is an environmentally widespread organism that causes blackleg and soft rot disease in potatoes. This organism produces pectolytic enzymes that destroy plant tissue and allow the bacteria to spread.