Rickettsia africae ESF-5

Rickettsia_africae
Names Rickettsia africae ESF-5
Accession numbers NC_012633, NC_012634
Background Rickettsiae are obligate intracellular Gram-negative bacteria mostly found in arthropods, some of which cause mild to severe diseases in humans. Over the last ten years, Rickettsia africae has emerged as the causative agent of African tick-bite fever, the most common spotted fever group (SFG) rickettsiosis. It's success as an infectious agent is probably due in part to increased tourism, and it is now found in the Caribbean, probably due to importation of infected cattle. It is highly prevalent in its host ticks (Amblyomma sp.), being present in up to 100%; in addition it does not seem to be detrimental to its hosts. By comparison with R. conorii, the second most prevalent SFG rickettsia in Africa (RICCN) R. africae exhibits a higher prevalence in ticks, a lower virulence in humans, and a greater genetic homogeneity. It may be a recently emerged species. Interestingly in the Rickettsia increased virulence results from gene inactivation. The ESF-5 strain, first isolated in from an Amblyomma variegatum tick collected from cattle in the Shulu province of Ethiopia in 1966, may have undergone loss or rearrangement of plasmid or chromosomal genes during multiple passages in cell culture. It also appears that depending on the geographic location, the plasmid of R. africae may be unstable (adapted from PubMed 19379498). (EBI Integr8)
Taxonomy
Kingdom:Bacteria
Phylum:Proteobacteria
Class:Alphaproteobacteria
Order:Rickettsiales
Family:Rickettsiaceae
Genus:Rickettsia
Species:africae
Strain ESF5
Complete Yes
Sequencing centre (14-APR-2009) Unite des Rickettsies, Faculte de Medecine, 27 Blvd Jean Moulin, Marseille cedex5 13385, France
(29-APR-2009) National Center for Biotechnology Information, NIH, Bethesda, MD 20894, USA
Sequencing quality Level 6: Finished
Sequencing depth NA
Sequencing method WGS
Isolation site Cattle tick Amblyomma variegatum collected in Ethiopia
Isolation country Ethiopia
Number of replicons 2
Gram staining properties Negative
Shape Bacilli
Mobility No
Flagellar presence No
Number of membranes 2
Oxygen requirements Aerobic
Optimal temperature NA
Temperature range Mesophilic
Habitat HostAssociated
Biotic relationship Symbiotic
Host name Homo sapiens
Cell arrangement NA
Sporulation Nonsporulating
Metabolism NA
Energy source NA
Diseases African Tick-Bite Fever
Pathogenicity Yes