Flavobacterium psychrophilum JIP02/86

Names Flavobacterium psychrophilum JIP02/86
Accession numbers NC_009613
Background Flavobacterium psychrophilum, a Gram-negative bacterium affecting diverse species of salmon and trout reared in freshwater, is currently one of the most devastating fish pathogens. As the outbreak of the disease occurs between 3 and 15 degrees Celsius, this bacterium is referred to as psychrophilum. The presence of F. psychrophilum within salmonid eggs and the resulting vertical transmission from broodfish to progeny suggest that this obligate fish pathogen has spread through the international trade of live fish and fish eggs. Adult fish suffer from the cold-water disease, a condition that results from extensive necrotic lesions, whereas young fish are affected by the rainbow trout fry syndrome, a hemorrhagic septicemia associated with severe mortality. Infection by F. psychrophilum results in considerable economic losses in salmonid aquaculture worldwide. The genome of Flavobacterium psychrophilum is made up of a single circular chromosome of 2,861,988 base pairs and a cryptic plasmid. F. psychrophilum contains 13 putative secreted proteases that are probably involved in virulence and/or destruction of host tissues. It moves over surfaces by gliding motility, a movement that does not involve pili or flagella. In accordance to this, 13 of the 15 gld genes involved in the gliding motility of F. johnsonniae were found. 27 genes probably involved in bacterial adhesion were identified. Four proteins similar to alginate-O-acetyltransferases of P. aeruginosa are likely to be involved in biofilm formation. ABC transport systems, the Sec-dependent system, the Tat-system and the components of the main terminal branch of the general secretory pathway are all present. It lacks the type III and IV secretion systems but possesses the PorT and PorR proteins which, in Porphyromonas gingivalis, are essential for major virulence factor transport and biosynthesis of polysaccharides serving as cell surface anchors for these factors. In agreement with its strictly aerobic metabolism, it possesses an extensive aerobic respiratory chain. Several genes encoding enzymes probably counteracting deleterious effects of reactive oxygen species (ROS) were identified, in accordance with the necessity for F. psychrophilum to resist ROS produced by the host macrophages in order to establish infection. (EBI Integr8)
Strain JIP02/86
Complete Yes
Sequencing centre (14-SEP-2002) National Center for Biotechnology Information, NIH, Bethesda, MD 20894, USA
(31-AUG-2006) Loux V., Unite MIG, Duchaud E., Unite VIM, I.N.R.A, Domaine de Vilvert, 78352 Jouy en Josas Cedex, FRANCE
Sequencing quality Level 6: Finished
Sequencing depth NA
Sequencing method Sanger
Isolation site "Kidney of a rainbow trout fry, Oncorhynchus mykiss"
Isolation country France
Number of replicons 1
Gram staining properties Negative
Shape Bacilli
Mobility No
Flagellar presence No
Number of membranes 2
Oxygen requirements Aerobic
Optimal temperature NA
Temperature range Psychrophilic
Habitat Aquatic
Biotic relationship Free living
Host name NA
Cell arrangement NA
Sporulation Nonsporulating
Metabolism NA
Energy source NA
Diseases Cold water disease, rainbow trout fry syndrome
Pathogenicity No