Proposal to Create Subspecies of Rickettsia sibirica and an Emended Description of Rickettsia sibirica

Abstract:  The Rickettsia sibirica species is composed of isolates that are genotypically close but can be classified within two distinct serotypes, that is, R. sibirica sensu stricto and R. sibirica mongolitimonae (incorrectly named R. mongolotimonae). We investigated the possibility of classifying rickettsiae closely related to R. sibirica as R. sibirica subspecies, as proposed by the ad hoc Committee on Reconciliation of Approaches to Bacterial Systematics. For this, we first estimated the genotypic variability by using multilocus sequence typing (MLST), including the sequencing of five genes, and multispacer typing (MST) using three intergenic spacers, of five isolates and three tick amplicons of R. sibirica sensu stricto and six isolates of R. sibirica mongolotimonae. Then, we selected a representative of each MLST genotype and used mouse serotyping to estimate their degree of taxonomic relatedness. Among the 14 isolates or tick amplicons studied, 2 MLST genotypes were identified: (i) the R. sibirica sensu stricto type; and (ii) the R. sibirica mongolitimonae type. Representatives of the two MLST types were classified within three MST types and into two serotypes. Therefore, as isolates within the R. sibirica species are genotypically homogeneous but show MST genotypic, serotypic, and epidemio‐clinical dissimilarities, we propose to modify the nomenclature of the R. sibirica species through the creation of subspecies. We propose the names R. sibirica subsp. sibirica subsp. nov. (type strain = 2‐4‐6, ATCC VR‐541T), and R. sibirica subsp. mongolitimonae subsp. nov. (type strain = HA‐91, ATCC VR‐1526T). The description of R. sibirica is emended to accommodate the two subspecies.

[1]  D. Raoult,et al.  Lymphangitis-associated rickettsiosis, a new rickettsiosis caused by Rickettsia sibirica mongolotimonae: seven new cases and review of the literature. , 2005, Clinical infectious diseases : an official publication of the Infectious Diseases Society of America.

[2]  D. Raoult,et al.  Proposal to create subspecies of Rickettsia conorii based on multi-locus sequence typing and an emended description of Rickettsia conorii , 2005, BMC Microbiology.

[3]  H. Ogata,et al.  Use of Highly Variable Intergenic Spacer Sequences for Multispacer Typing of Rickettsia conorii Strains , 2004, Journal of Clinical Microbiology.

[4]  Jianzhi Zhang,et al.  Gene Sequence-Based Criteria for Identification of New Rickettsia Isolates and Description of Rickettsia heilongjiangensis sp. nov , 2003, Journal of Clinical Microbiology.

[5]  D. Raoult,et al.  Detection and identification of spotted fever group Rickettsiae and Ehrlichiae in African ticks. , 2001, Emerging infectious diseases.

[6]  D. Raoult,et al.  Phylogeny of Rickettsia spp. inferred by comparing sequences of 'gene D', which encodes an intracytoplasmic protein. , 2001, International journal of systematic and evolutionary microbiology.

[7]  D. Raoult,et al.  Phylogenetic analysis of members of the genus Rickettsia using the gene encoding the outer-membrane protein rOmpB (ompB). , 2000, International journal of systematic and evolutionary microbiology.

[8]  D. Raoult,et al.  Phylogenetic analysis of the Chinese Rickettsia isolate BJ-90. , 2000, Emerging infectious diseases.

[9]  D. Raoult,et al.  Phylogenetic analysis of spotted fever group rickettsiae by study of the outer surface protein rOmpA. , 1998, International journal of systematic bacteriology.

[10]  D Raoult,et al.  Citrate synthase gene comparison, a new tool for phylogenetic analysis, and its application for the rickettsiae. , 1997, International journal of systematic bacteriology.

[11]  D. Raoult,et al.  Differentiation of spotted fever group rickettsiae by sequencing and analysis of restriction fragment length polymorphism of PCR-amplified DNA of the gene encoding the protein rOmpA , 1996, Journal of clinical microbiology.

[12]  D. Raoult,et al.  A new spotted-fever-group Rickettsiosis , 1996, The Lancet.

[13]  D. Raoult,et al.  Phylogenetic analysis of the genus Rickettsia by 16S rDNA sequencing. , 1995, Research in microbiology.

[14]  J. Thompson,et al.  CLUSTAL W: improving the sensitivity of progressive multiple sequence alignment through sequence weighting, position-specific gap penalties and weight matrix choice. , 1994, Nucleic acids research.

[15]  D. Raoult,et al.  Proteinic and genomic identification of spotted fever group rickettsiae isolated in the former USSR , 1993, Journal of clinical microbiology.

[16]  D. Raoult,et al.  Genotypic and antigenic identification of two new strains of spotted fever group rickettsiae isolated from China , 1993, Journal of clinical microbiology.

[17]  P. Mason,et al.  Serological typing of spotted fever group Rickettsia isolates from Zimbabwe , 1990, Journal of clinical microbiology.

[18]  Lawrence G. Wayne,et al.  International Committee on Systematic Bacteriology: Announcement of the Report of the Ad Hoc Committee on Reconciliation of Approaches to Bacterial Systematics , 1988 .

[19]  W. Burgdorfer,et al.  Serologic typing of rickettsiae of the spotted fever group by microimmunofluorescence. , 1978, Journal of immunology.

[20]  H. Stoenner,et al.  Immunologic relationships among the spotted fever group of rickettsias determined by toxin neutralization tests in mice with convalescent animal serums. , 1960, Journal of immunology.