Rickettsia felis: molecular characterization of a new member of the spotted fever group.

ABSTRACT Many species of Rickettsia are well-known mammalian pathogens transmitted by blood-feeding arthropods. However, molecular surveys are continually uncovering novel Rickettsia species, often in unexpected hosts, including many arthropods that do not feed on blood. This study reports a systematic molecular characterization of a Rickettsia infecting the psocid Liposcelis bostrychophila (Psocoptera: Liposcelidae), a common and cosmopolitan household pest. Surprisingly, the psocid Rickettsia is shown to be Rickettsia felis, a human pathogen transmitted by fleas that causes serious morbidity and occasional mortality. The plasmid from the psocid R. felis was sequenced and was found to be virtually identical to the one in R. felis from fleas. As Liposcelis insects are often intimately associated with humans and other vertebrates, it is speculated that they acquired R. felis from fleas. Whether the R. felis in psocids causes disease in vertebrates is not known and warrants further study.

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Characterization of Mutations in therpoB Gene in Naturally Rifampin-ResistantRickettsia Species

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.43.10.2400 ◽

1999 ◽

Vol 43 (10) ◽

pp. 2400-2403 ◽

Cited By ~ 35

Author(s):

Michel Drancourt ◽

Didier Raoult

Keyword(s):

Spotted Fever ◽

Single Point ◽

Experimental Studies ◽

Single Point Mutation ◽

Rickettsia Conorii ◽

Spotted Fever Group ◽

Resistant Species ◽

Encoding Gene ◽

Group Species

ABSTRACT Rickettsiae are gram-negative, obligately intracellular bacteria responsible for arthropod-borne spotted fevers and typhus. Experimental studies have delineated a cluster of naturally rifampin-resistant spotted fever group species. We sequenced the 4,122- to 4,125-bp RNA polymerase β-subunit-encoding gene (rpoB) from typhus and spotted fever group representatives and obtained partial sequences for all naturally rifampin-resistant species. A single point mutation resulting in a phenylalanine-to-leucine change at position 973 of theRickettsia conorii rpoB sequence and present in all the rifampin-resistant species was absent in all the rifampin-susceptible species. rpoB-based phylogenetic relationships among these rickettsial species yielded topologies which were in accordance with previously published phylogenies.

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Detection and characterization of a novel spotted fever group Rickettsia genotype in Haemaphysalis leporispalustris from California, USA

Ticks and Tick-borne Diseases ◽

10.1016/j.ttbdis.2018.02.023 ◽

2018 ◽

Vol 9 (4) ◽

pp. 814-818 ◽

Cited By ~ 10

Author(s):

Marina E. Eremeeva ◽

Lindsey M. Weiner ◽

Maria L. Zambrano ◽

Gregory A. Dasch ◽

Renjie Hu ◽

...

Keyword(s):

Spotted Fever ◽

Spotted Fever Group ◽

Spotted Fever Group Rickettsia

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Application of the Numerical Characteristic of Formal Order Analysis of the Prokaryotic Genomes for Reclassification within the Genus Rickettsia

Математическая биология и биоинформатика ◽

10.17537/2016.11.336 ◽

2016 ◽

Vol 11 (2) ◽

pp. 336-350 ◽

Cited By ~ 3

Author(s):

С.Н. Шпынов ◽

S.N. Shpynov

Keyword(s):

Spotted Fever ◽

Numerical Characteristic ◽

Spotted Fever Group ◽

Rickettsia Felis ◽

New Approach ◽

Order Analysis ◽

Ancestral Group ◽

Prokaryotic Genomes ◽

Information Chain

Genomes representing Rickettsiaceae family were analyzed using formal order analysis (FOA) of information chain in order to develop a new approach for the classification of prokaryotes. Average remoteness – the numerical characteristic of order was used to compare the genomes. FOA allows one to directly take into account arrangement of nucleotides in each sequence. The obtained results clarified the previously known classification. In addition Rickettsia felis group was discovered between the ancestral group and spotted fever group (SFG) and R. akari group located between the SFG and genus Orientia. Software used for the analysis of nucleotide sequences with FOA is freely available at http://foarlab.org.

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