The Isolation of Strains of Rickettsiae of the Spotted Fever Group in Israel and their Differentiation from other Members of the Group by Immunofluorescence Methods

Goldwasser, Robert A.; Steiman, Yonel; Klingberg, Wanda; Swartz, T. A.; Klingberg, Marcus A.

doi:10.3109/inf.1974.6.issue-1.10

Cited by 62 publications

(34 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Finally, in order to estimate the applicability of our genetic criteria, we applied them to seven rickettsiae previously classified as members of the spotted fever group, i.e., "Rickettsia mongolotimonae" (66), which is phylogenetically closely related to R. sibirica on the basis of genotypic and phenotypic criteria (66); BJ-90 (70), which is considered an R. sibirica strain or subspecies on the basis of genotypic data; strain S (14), which has not been found to be phenotypically and genotypically different enough from R. africae to be classified as a new species; two members of the R. conorii complex, Israeli spotted fever rickettsia (17) and Astrakhan fever rickettsia (15), both of which are considered at present to belong to the species R. conorii (59); Bar 29 (4), which is considered to belong to R. massiliae; and "R. heilongjiangii" (69), a Chinese strain most closely related to R. japonica but considered a separate species on the basis of epidemiological characteristics and the mouse serotyping assay.…”

Section: Methodsmentioning

confidence: 99%

Gene Sequence-Based Criteria for Identification of NewRickettsiaIsolates and Description ofRickettsia heilongjiangensissp. nov

et al. 2003

View full text Add to dashboard Cite

We propose genetic guidelines for the classification of rickettsial isolates at the genus, group, and species levels by using sequences of the 16S rRNA (rrs) gene and four protein-coding genes, the gltA, ompA, and ompB genes and gene D. To be classified as a member of the genus Rickettsia, an isolate should exhibit degrees of rrs and gltA homology with any of the 20 Rickettsia species studied of >98.1 and >86.5%, respectively. A member of the typhus group should fulfill at least two of the following four criteria: pairwise nucleotide sequence homologies with rrs, gltA, ompB, and gene D of either Rickettsia typhi or Rickettsia prowazekii of >99.4, >96.6, >92.4, and >91.6%, respectively. A member of the spotted fever group should either possess the ompA gene or fulfill at least two of the following four criteria: pairwise nucleotide sequence homologies with rrs, gltA, ompB, and gene D of any member of this group of >98.8, >92.7, >85.8, and >82.2%, respectively. The existence of a distinct "ancestral" group should be questioned. To be classified as a new Rickettsia species, an isolate should not exhibit more than one of the following degrees of nucleotide similarity with the most homologous validated species: >99.8 and > 99.9% for the rrs and gltA genes, respectively, and, when amplifiable, >98.8, >99.2, and >99.3% for the ompA and ompB genes and gene D, respectively. By use of our classification scheme, "Rickettsia heilongjiangii" belongs to a new species for which we officially propose the name Rickettsia heilongjiangensis sp. nov.The order Rickettsiales initially consisted of most of the bacteria associated with eukaryotic cells (63). On the basis of their 16S rRNA gene (rrs) sequences, Rickettsiella grylli, Coxiella burnetii, Wolbachia persica, Rochalimaea spp., Grahamella spp., Bartonella spp., Eperithrozoon ovis, and Hemobartonella spp. have been removed from the order Rickettsiales (5,7,41,43,62), which comprises only the genera Rickettsia, Orientia, Ehrlichia, Anaplasma, Neorickettsia, and Wolbachia. Historically, the genus Rickettsia was divided into three groups on the basis of phenotypic criteria: the typhus group, the spotted fever group, and the scrub typhus group (63). In 1995, Tamura et al. (53) proposed reclassification of Rickettsia tsutsugamushi (33) into a new genus, Orientia, using 16S rRNA gene sequence analysis. The same year, Stothard and Fuerst (52) suggested that Rickettsia bellii (36) and Rickettsia canadensis (27) represented a phylogenetic line that predated the typhus-spotted fever group split and, thus, were included into a fourth group named the "ancestral" group. At present, the genus Rickettsia contains 21 validated species classified into three groups: (i) the ancestral group described above; (ii) the typhus group, which includes Rickettsia prowazekii (12) and Rickettsia typhi (34); and (iii) the spotted fever group, which consists of Rickettsia rickettsii (9), Rickettsia conorii (10), Rickettsia africae (20), Rickettsia sibirica (67), Rickettsia slovaca (48), Rickettsia honei (5...

show abstract

Section: Methodsmentioning

confidence: 99%

Gene Sequence-Based Criteria for Identification of NewRickettsiaIsolates and Description ofRickettsia heilongjiangensissp. nov

et al. 2003

View full text Add to dashboard Cite

show abstract

“…3, 4, 8, and 10) appear to mirror the subtle serologic nonidentity reported to occur among the same Mediterranean SFG group rickettsial isolates (16).…”

mentioning

confidence: 99%

Genotypic identification of rickettsiae and estimation of intraspecies sequence divergence for portions of two rickettsial genes

1991

View full text Add to dashboard Cite

DNA sequences from specific genes, amplified by the polymerase chain reaction technique, were used as substrata for nonisotopic restriction endonuclease fragment klgth polymorphism differentiation of rickettsial species and genotypes. The products amplified using a single pai of oligonucleotide primers (derived from a rickettsial citrate synthase gene sequence) and cleaved with restriction endonucleases were used to differentiate almost all recognized species of rickettsiae. A second set of primers was used for differentiation of al recognized species of closely related spotted fever group rickettsiae. The procedure circumvents many technical obstacles previously associated with identification of rickettsial species. Multiple amplified DNA digest patterns were used to estimate the intraspecies nucleotide sequence divergence for the genes coding for rickettsial citrate synthase and a large antigen-coding gene of the spotted fever group rickettsiae. The estimted relationships deduced from these genotypic data correlate reasonably well with established rickettsial taxonomic schemes.

show abstract

“…were grown in yolk sacs of embryonate hen eggs, as described previously. 5 Quantitative estimation of R. conorii and R. typhi was obtained by counting immunofluorescence-stained rickettsiae.…”

Section: Introductionmentioning

confidence: 99%

Polymerase chain reaction-based diagnosis of Mediterranean spotted fever in serum and tissue samples.

Leitner¹,

Yitzhaki²,

Rzotkiewicz³

et al. 2002

The American Journal of Tropical Medicine and Hygiene

View full text Add to dashboard Cite

Abstract. A nested polymerase chain reaction (PCR) assay has been developed and used in the diagnosis of fatal and benign cases of Mediterranean spotted fever (MSF). The test was based on specific primers derived from a Rickettsia conorii 17-kD protein gene. A positive signal was obtained from spotted fever group (SFG) and typhus group (TG) rickettsiae. Discrimination between SFG and TG rickettsiae was based on a restriction fragment length polymorphism test. Other gram-negative bacterial species tested did not generate a signal, attesting for the specificity of the assay. The SFG-specific DNA fragment was detected in four of 29 acute-phase sera from serologically confirmed patients with MSF, while acute-phase sera from 25 patients without MSF were PCR negative. Acute-phase sera samples (five of five) and tissue autopsies (six of seven) from fatal suspected cases of MSF were PCR positive. The results demonstrate that sera and tissue samples are suitable specimens for the nested PCR tests, especially in fatal cases.

show abstract

The Isolation of Strains of Rickettsiae of the Spotted Fever Group in Israel and their Differentiation from other Members of the Group by Immunofluorescence Methods

Cited by 62 publications

References 9 publications

Gene Sequence-Based Criteria for Identification of NewRickettsiaIsolates and Description ofRickettsia heilongjiangensissp. nov

Gene Sequence-Based Criteria for Identification of NewRickettsiaIsolates and Description ofRickettsia heilongjiangensissp. nov

Genotypic identification of rickettsiae and estimation of intraspecies sequence divergence for portions of two rickettsial genes

Polymerase chain reaction-based diagnosis of Mediterranean spotted fever in serum and tissue samples.

Contact Info

Product

Resources

About