Rickettsia bellii OSU 85-389

Names Rickettsia bellii OSU 85-389
Accession numbers NC_009883
Background Rickettsia bellii (strain RML369-C) was isolated in embryonated chicken eggs from a triturated pool of unfed adult Dermacentor variabilis ticks collected from vegetation near Fayetteville, Arkansas, in June of 1966. R.bellii is the most common rickettsia found in ticks in America, in which it is transovarially transmitted. It has been found in various hard ticks including species of Dermacentor and Amblyomma. It is also the sole rickettsia found in both soft and hard ticks, therefore exhibiting the largest arthropod host range among known rickettsiae. Its genome is made up of a single circular chromosome. Several transposase genes of R.bellii are split into two ORFs. It possesses genes for toxin antitoxin systems (8 for toxin and 9 for antitoxin) as well as 10 paralogous genes for spoT. It has a tra gene cluster predicted to encode a type IV secretion system (T4SS) for conjugal DNA transfer. The tra gene cluster is composed of a "F-like region" and a "Ti-like region". This tra gene cluster thus encodes the most complete DNA transfer machinery found so far in Rickettsia. Transmission electron microscopy has revealed the presence of pili on the surface of R.bellii. They are long and flexible and connect bacteria with each other. They are likely to be involved in the early stages of conjugation. In guinea pigs and rabbits intradermal injection of 50 R.bellii caused slight inflammatory reactions, and inoculation of 50,000 R.bellii induced a black necrotic eschar. (EBI Integr8)
Strain OSU 85-389
Complete Yes
Sequencing centre (16-SEP-2004) National Center for Biotechnology Information, NIH, Bethesda, MD 20894, USA
(27-SEP-2007) Neurogenomics Research Lab, University of Iowa, 200 B EMRB, Iowa City, IA 52242, USA
Sequencing quality Level 6: Finished
Sequencing depth NA
Sequencing method Sanger
Isolation site Isolated in Vero cell culture at 34 C by Karl Poetter and Chip Pretzman; spaghetti forms seen
Isolation country USA
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 Mesophilic
Habitat HostAssociated
Biotic relationship Symbiotic
Host name Dermacentor variabilis, Homo sapiens
Cell arrangement NA
Sporulation Nonsporulating
Metabolism NA
Energy source NA
Diseases NA
Pathogenicity NA