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Khosravi G, Akbarzadeh K, Karimian F, Koosha M, Saeedi S, Oshaghi MA. A survey of Wolbachia infection in brachyceran flies from Iran. PLoS One 2024; 19:e0301274. [PMID: 38776328 PMCID: PMC11111063 DOI: 10.1371/journal.pone.0301274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 03/13/2024] [Indexed: 05/24/2024] Open
Abstract
Wolbachia is a maternally inherited intracellular bacterium that is considered to be the most plentiful endosymbiont found in arthropods. It reproductively manipulates its host to increase the chances of being transmitted to the insect progeny; and it is currently used as a means of suppressing disease vector populations or controlling vector-borne diseases. Studies of the dissemination and prevalence of Wolbachia among its arthropod hosts are important for its possible use as a biological control agent. The molecular identification of Wolbachia relies on different primers sets due to Wolbachia strain variation. Here, we screened for the presence of Wolbachia in a broad range of Brachycera fly species (Diptera), collected from different regions of Iran, using nine genetic markers (wsp, ftsZ, fbpA, gatB, CoxA, gltA, GroEL dnaA, and 16s rRNA), for detecting, assessing the sensitivity of primers for detection, and phylogeny of this bacterium. The overall incidence of Wolbachia among 22 species from six families was 27.3%. The most commonly positive fly species were Pollenia sp. and Hydrotaea armipes. However, the bacterium was not found in the most medically important flies or in potential human disease vectors, including Musca domestica, Sarcophaga spp., Calliphora vicinia, Lucilia sericata, and Chrysomya albiceps. The primer sets of 16s rRNA with 53.0% and gatB with 52.0% were the most sensitive primers for detecting Wolbachia. Blast search, phylogenetic, and MLST analysis of the different locus sequences of Wolbachia show that all the six distantly related fly species likely belonging to supergroup A. Our study showed some primer sets generated false negatives in many of the samples, emphasizing the importance of using different loci in detecting Wolbachia. The study provides the groundwork for future studies of a Wolbachia-based program for control of flies.
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Affiliation(s)
- Ghazal Khosravi
- Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Kamran Akbarzadeh
- Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Fateh Karimian
- Department of Parasitology, Pasteur Institute of Iran, Tehran, Iran
| | - Mona Koosha
- Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Shahin Saeedi
- Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammad Ali Oshaghi
- Department of Vector Biology and Control of Diseases, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
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Diversity unearthed by the estimated molecular phylogeny and ecologically quantitative characteristics of uncultured Ehrlichia bacteria in Haemaphysalis ticks, Japan. Sci Rep 2021; 11:687. [PMID: 33436999 PMCID: PMC7804854 DOI: 10.1038/s41598-020-80690-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 12/24/2020] [Indexed: 11/09/2022] Open
Abstract
Ehrlichia species are obligatory intracellular bacteria transmitted by arthropods, and some of these species cause febrile diseases in humans and livestock. Genome sequencing has only been performed with cultured Ehrlichia species, and the taxonomic status of such ehrlichiae has been estimated by core genome-based phylogenetic analysis. However, many uncultured ehrlichiae exist in nature throughout the world, including Japan. This study aimed to conduct a molecular-based taxonomic and ecological characterization of uncultured Ehrlichia species or genotypes from ticks in Japan. We first surveyed 616 Haemaphysalis ticks by p28-PCR screening and analyzed five additional housekeeping genes (16S rRNA, groEL, gltA, ftsZ, and rpoB) from 11 p28-PCR-positive ticks. Phylogenetic analyses of the respective genes showed similar trees but with some differences. Furthermore, we found that V1 in the V1-V9 regions of Ehrlichia 16S rRNA exhibited the greatest variability. From an ecological viewpoint, the amounts of ehrlichiae in a single tick were found to equal approx. 6.3E+3 to 2.0E+6. Subsequently, core-partial-RGGFR-based phylogenetic analysis based on the concatenated sequences of the five housekeeping loci revealed six Ehrlichia genotypes, which included potentially new Ehrlichia species. Thus, our approach contributes to the taxonomic profiling and ecological quantitative analysis of uncultured or unidentified Ehrlichia species or genotypes worldwide.
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McKenzie HC, Funk RA, Trager L, Werre SR, Crisman M. Immunogenicity of Potomac horse fever vaccine when simultaneously co-administered with rabies vaccine in a multivalent vaccine or as two monovalent vaccines at separate sites. Equine Vet J 2019; 51:774-778. [PMID: 30859618 PMCID: PMC6850380 DOI: 10.1111/evj.13096] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 03/02/2019] [Indexed: 11/29/2022]
Abstract
Background Potomac horse fever (PHF) is a potentially fatal enterocolitis of horses caused by Neorickettsia risticii. The disease was originally recognised almost 40 years ago in the state of Maryland in the US. It is now known to occur in many areas of North America, as well as having been described in South America and Europe. Monocomponent PHF vaccines are available, but clinical protection with vaccination has been reported to be inconsistent. Objectives This study was designed to assess the immunogenicity of a commercially available Potomac Horse Fever (PHF) vaccine when administered as either a monovalent PHF vaccine simultaneously co‐administered with a separate monovalent Rabies vaccine or as a multivalent PHF/Rabies vaccine in horses. Study design Randomised parallel group trial. Methods Ninety‐one client or University owned horses participated in this open‐label randomised study, with 45 horses receiving the monovalent vaccines at separate sites and 46 receiving the multivalent vaccine at a single site. Serum PHF IFA titres were determined twice prior to vaccination and at 1, 2 and 3 months after vaccination. Results Both vaccination protocols exhibited poor immunogenicity, with only one‐third of all the animals demonstrating seroconversion, defined as an increase in titre of greater than 400 over baseline, at any time point after vaccination. The monovalent PHF vaccine exhibited significantly greater immunogenicity in terms of the number of horses exhibiting seroconversion, as compared to the multivalent vaccine, at one (20 vs. 11, P = 0.03) and two (18 vs. 9, p = 0.02) months post vaccination. The monovalent PHF vaccine also exhibited significantly greater immunogenicity in terms of the median (interquartile range) IFA titres, as compared to the multivalent vaccine, at one (800 [200–1600] vs. 400 [200–800], P = 0.009) and 2 months (400 [200–1600] vs. 400 [100–800], P = 0.02) post vaccination. There was no significant difference between groups at 3 months in either seroconversion rate or median IFA titers. Main limitations This study did not assess the actual protective effects of PHF vaccination but rather used the serologic response to vaccination as a surrogate biomarker of immunity. Conclusions The multivalent PHF/Rabies vaccine exhibited lower immunogenicity as compared to the monovalent PHF vaccine co‐administered with a separate Rabies vaccine.
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Affiliation(s)
- H C McKenzie
- Department of Large Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - R A Funk
- Department of Large Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - L Trager
- Department of Large Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - S R Werre
- Laboratory for Study Design and Statistical Analysis, Department of Biomedical Sciences and Pathobiology, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
| | - M Crisman
- Department of Large Animal Clinical Sciences, Virginia Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, USA
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Natural Anaplasmataceae infection in Rhipicephalus bursa ticks collected from sheep in the French Basque Country. Ticks Tick Borne Dis 2016; 8:18-24. [PMID: 27666778 DOI: 10.1016/j.ttbdis.2016.09.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 09/13/2016] [Accepted: 09/18/2016] [Indexed: 11/21/2022]
Abstract
Rhipicephalus bursa is one of 79 species of the genus Rhipicephalus in the family of Ixodidae. In this study, we investigated Anaplasmataceae bacteria associated with R. bursa collected after an epizootic outbreak of ovine anaplasmosis. 76 adult ticks, (60 male and 16 female ticks), were removed from sheep in two farms and all identified as R. bursa, all females were partially engorged. We found that 50% of the ticks were positive in the initial Anaplasmataceae qPCR screening. Bacterial species was identified by analyzing the sequences of amplicons of 23S rRNA, groEL and rpoB genes. 22.4% of ticks contained DNA of Anaplasma phagocytophilum and 7.9% the DNA of Anaplasma ovis. Based on 23S rRNA and groEL genes analysis, we found that 19.7% of ticks contained a potentially new species of Ehrlichia. We propose the status of Candidatus for this uncultured species and we provisionally name it Candidatus Ehrlichia urmitei. No Wolbachia were identified. These results show that R. bursa can be a carrier of Anaplasmataceae bacteria.
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Pfannschmidt T, Blanvillain R, Merendino L, Courtois F, Chevalier F, Liebers M, Grübler B, Hommel E, Lerbs-Mache S. Plastid RNA polymerases: orchestration of enzymes with different evolutionary origins controls chloroplast biogenesis during the plant life cycle. JOURNAL OF EXPERIMENTAL BOTANY 2015; 66:6957-73. [PMID: 26355147 DOI: 10.1093/jxb/erv415] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Chloroplasts are the sunlight-collecting organelles of photosynthetic eukaryotes that energetically drive the biosphere of our planet. They are the base for all major food webs by providing essential photosynthates to all heterotrophic organisms including humans. Recent research has focused largely on an understanding of the function of these organelles, but knowledge about the biogenesis of chloroplasts is rather limited. It is known that chloroplasts develop from undifferentiated precursor plastids, the proplastids, in meristematic cells. This review focuses on the activation and action of plastid RNA polymerases, which play a key role in the development of new chloroplasts from proplastids. Evolutionarily, plastids emerged from the endosymbiosis of a cyanobacterium-like ancestor into a heterotrophic eukaryote. As an evolutionary remnant of this process, they possess their own genome, which is expressed by two types of plastid RNA polymerase, phage-type and prokaryotic-type RNA polymerase. The protein subunits of these polymerases are encoded in both the nuclear and plastid genomes. Their activation and action therefore require a highly sophisticated regulation that controls and coordinates the expression of the components encoded in the plastid and nucleus. Stoichiometric expression and correct assembly of RNA polymerase complexes is achieved by a combination of developmental and environmentally induced programmes. This review highlights the current knowledge about the functional coordination between the different types of plastid RNA polymerases and provides working models of their sequential expression and function for future investigations.
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Affiliation(s)
- Thomas Pfannschmidt
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
| | - Robert Blanvillain
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
| | - Livia Merendino
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
| | - Florence Courtois
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
| | - Fabien Chevalier
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
| | - Monique Liebers
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
| | - Björn Grübler
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
| | - Elisabeth Hommel
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
| | - Silva Lerbs-Mache
- Université Grenoble-Alpes, F-38000 Grenoble, France CNRS, UMR5168, F-38054 Grenoble, France CEA, iRTSV, Laboratoire de Physiologie Cellulaire & Végétale, F-38054 Grenoble, France INRA, USC1359, F-38054 Grenoble, France
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Tate CM, Howerth EW, Mead DG, Dugan VG, Luttrell MP, Sahora AI, Munderloh UG, Davidson WR, Yabsley MJ. Anaplasma odocoilei sp. nov. (family Anaplasmataceae) from white-tailed deer (Odocoileus virginianus). Ticks Tick Borne Dis 2012; 4:110-9. [PMID: 23276749 DOI: 10.1016/j.ttbdis.2012.09.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2011] [Revised: 09/11/2012] [Accepted: 09/24/2012] [Indexed: 11/16/2022]
Abstract
Recently, an undescribed Anaplasma sp. (also called Ehrlichia-like sp. or WTD agent) was isolated in ISE6 tick cells from captive white-tailed deer. The goal of the current study was to characterize this organism using a combination of experimental infection, morphologic, serologic, and molecular studies. Each of 6 experimentally inoculated white-tailed deer fawns (Odocoileus virginianus) became chronically infected (100+ days) with the Anaplasma sp. by inoculation of either infected whole blood or culture. None of the deer showed evidence of clinical disease, but 3 of the 6 deer evaluated had multiple episodes of transient thrombocytopenia. Light microscopy of Giemsa-stained, thin blood smears revealed tiny, dark, spherical structures in platelets of acutely infected deer. Anaplasma sp. was detected in platelets of inoculated deer by polymerase chain reaction, transmission electron microscopy, immunohistochemistry, and in situ hybridization. Five of 6 deer developed antibodies reactive to Anaplasma sp. antigen, as detected by indirect fluorescent antibody testing. Phylogenetic analyses of 16S rRNA, groESL, and gltA sequences confirmed the Anaplasma sp. is related to A. platys. Two attempts to transmit the Anaplasma sp. between deer by feeding Amblyomma americanum, a suspected tick vector, were unsuccessful. Based on its biologic, antigenic, and genetic characteristics, this organism is considered a novel species of Anaplasma, and the name Anaplasma odocoilei sp. nov. is proposed with UMUM76(T) (=CSUR-A1) as the type strain.
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Affiliation(s)
- Cynthia M Tate
- Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA
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André MR, Dumler JS, Scorpio DG, Teixeira RHF, Allegretti SM, Machado RZ. Molecular detection of tick-borne bacterial agents in Brazilian and exotic captive carnivores. Ticks Tick Borne Dis 2012; 3:247-53. [PMID: 22749737 DOI: 10.1016/j.ttbdis.2012.04.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 04/19/2012] [Accepted: 04/24/2012] [Indexed: 11/28/2022]
Abstract
The present study aims to detect and characterize by molecular techniques, the presence of tick-borne pathogens in wild captive carnivore blood samples from Brazil. Blood was collected from 76 Brazilian felids, 23 exotic felids, 3 European wolves (Canis lupus), and 97 Brazilian canids maintained in captivity in zoos located in São Paulo and Mato Grosso states, Brazil. DNA of each sample was used in PCR reactions for Ehrlichia, Anaplasma, and Rickettsia identification. The blood from 10/100 (10%) of canids (1 European wolf, 3 bush dogs, and 6 crab-eating foxes) and from 21/99 (21%) felids (4 pumas, 6 little spotted cats, 4 ocelots, 3 jaguarundis, 1 tiger, and 3 lions) contained fragments of 16S rRNA gene of Ehrlichia spp. Fragments of Anaplasma spp. groESL and 16S rRNA genes were detected in the blood of 1/100 (1%) canids (1 bush dog) and in 4/99 (3%) felids (4 little spotted cats), respectively. Rickettsia species infections were not identified. The present work showed that new strains of Ehrlichia and Anaplasma spp. circulate among wild carnivores in Brazil.
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Affiliation(s)
- M R André
- Departamento de Patologia Veterinária, Faculdade de Ciências Agrárias e Veterinárias (FCAV), Universidade Estadual Paulista (UNESP), 14884-900 Jaboticabal, SP, Brazil
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Vaughan JA, Tkach VV, Greiman SE. Neorickettsial endosymbionts of the digenea: diversity, transmission and distribution. ADVANCES IN PARASITOLOGY 2012; 79:253-97. [PMID: 22726644 DOI: 10.1016/b978-0-12-398457-9.00003-2] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Digeneans are endoparasitic flatworms with complex life cycles and distinct life stages that parasitize different host species. Some digenean species harbour bacterial endosymbionts known as Neorickettsia (Order Rickettsiales, Family Anaplasmataceae). Neorickettsia occur in all life stages and are maintained by vertical transmission. Far from benign however, Neorickettsia may also be transmitted horizontally by digenean parasites to their vertebrate definitive hosts. Once inside, Neorickettsia can infect macrophages and other cell types. In some vertebrate species (e.g. dogs, horses and humans), neorickettsial infections cause severe disease. Taken from a mostly parasitological perspective, this article summarizes our current knowledge on the transmission ecology of neorickettsiae, both for pathogenic species and for neorickettsiae of unknown pathogenicity. In addition, we discuss the diversity, phylogeny and geographical distribution of neorickettsiae, as well as their possible evolutionary associations with various groups of digeneans. Our understanding of neorickettsiae is at an early stage and there are undoubtedly many more neorickettsial endosymbioses with digeneans waiting to be discovered. Because neorickettsiae can infect vertebrates, it is particularly important to examine digenean species that regularly infect humans. Rapid advances in molecular tools and their application towards bacterial identification bode well for our future progress in understanding the biology of Neorickettsia.
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Holloway C, Beiko RG. Assembling networks of microbial genomes using linear programming. BMC Evol Biol 2010; 10:360. [PMID: 21092133 PMCID: PMC3224671 DOI: 10.1186/1471-2148-10-360] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Accepted: 11/20/2010] [Indexed: 01/04/2023] Open
Abstract
Background Microbial genomes exhibit complex sets of genetic affinities due to lateral genetic transfer. Assessing the relative contributions of parent-to-offspring inheritance and gene sharing is a vital step in understanding the evolutionary origins and modern-day function of an organism, but recovering and showing these relationships is a challenging problem. Results We have developed a new approach that uses linear programming to find between-genome relationships, by treating tables of genetic affinities (here, represented by transformed BLAST e-values) as an optimization problem. Validation trials on simulated data demonstrate the effectiveness of the approach in recovering and representing vertical and lateral relationships among genomes. Application of the technique to a set comprising Aquifex aeolicus and 75 other thermophiles showed an important role for large genomes as 'hubs' in the gene sharing network, and suggested that genes are preferentially shared between organisms with similar optimal growth temperatures. We were also able to discover distinct and common genetic contributors to each sequenced representative of genus Pseudomonas. Conclusions The linear programming approach we have developed can serve as an effective inference tool in its own right, and can be an efficient first step in a more-intensive phylogenomic analysis.
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Affiliation(s)
- Catherine Holloway
- Faculty of Computer Science, Dalhousie University, 6050 University Avenue, Halifax, Nova Scotia B3 H 1W5, Canada
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Lane WJ, Darst SA. Molecular evolution of multisubunit RNA polymerases: sequence analysis. J Mol Biol 2010; 395:671-85. [PMID: 19895820 PMCID: PMC2813377 DOI: 10.1016/j.jmb.2009.10.062] [Citation(s) in RCA: 132] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2009] [Revised: 10/22/2009] [Accepted: 10/26/2009] [Indexed: 11/21/2022]
Abstract
Transcription in all cellular organisms is performed by multisubunit, DNA-dependent RNA polymerases that synthesize RNA from DNA templates. Previous sequence and structural studies have elucidated the importance of shared regions common to all multisubunit RNA polymerases. In addition, RNA polymerases contain multiple lineage-specific domain insertions involved in protein-protein and protein-nucleic acid interactions. We have created comprehensive multiple sequence alignments using all available sequence data for the multisubunit RNA polymerase large subunits, including the bacterial beta and beta' subunits and their homologs from archaebacterial RNA polymerases, the eukaryotic RNA polymerases I, II, and III, the nuclear-cytoplasmic large double-stranded DNA virus RNA polymerases, and plant plastid RNA polymerases. To overcome technical difficulties inherent to the large-subunit sequences, including large sequence length, small and large lineage-specific insertions, split subunits, and fused proteins, we created an automated and customizable sequence retrieval and processing system. In addition, we used our alignments to create a more expansive set of shared sequence regions and bacterial lineage-specific domain insertions. We also analyzed the intergenic gap between the bacterial beta and beta' genes.
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Affiliation(s)
- William J. Lane
- The Rockefeller University, Box 224, 1230 York Avenue, New York, NY 10021, USA
| | - Seth A. Darst
- The Rockefeller University, Box 224, 1230 York Avenue, New York, NY 10021, USA
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Headley SA, Scorpio DG, Vidotto O, Dumler JS. Neorickettsia helminthoeca and salmon poisoning disease: a review. Vet J 2009; 187:165-73. [PMID: 20044285 DOI: 10.1016/j.tvjl.2009.11.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Revised: 11/25/2009] [Accepted: 11/29/2009] [Indexed: 10/20/2022]
Abstract
Neorickettsia helminthoeca is an obligate intra-cytoplasmic bacterium that causes salmon poisoning disease (SPD), an acute, febrile, fatal disease of dogs. The complex life-cycle of this pathogen involves stages in an intestinal fluke (Nanophyetus salmincola), a river snail (Oxytrema silicula), in fish, and in fish-eating mammals. This complexity has created confusion with respect to the various bacterial and parasitic infections associated with the disease and its significance in dogs in specific geographical locations has likely to have previously been under-estimated. This paper addresses the history, taxonomy, microbiology of N. helminthoeca and summarises the pathogenesis, clinical signs and pathological features associated with infection. Furthermore, the biological cycles, treatment, control, and both public and veterinary health impacts associated with this pathogen and the intestinal fluke N. salmincola are discussed.
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Affiliation(s)
- Selwyn Arlington Headley
- Department of Basic Veterinary Sciences, School of Veterinary Medicine, St. Matthew's University, Grand Cayman, Cayman Islands, British West Indies.
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Yabsley MJ, Murphy SM, Luttrell MP, Wilcox BR, Howerth EW, Munderloh UG. Characterization of 'Candidatus Neoehrlichia lotoris' (family Anaplasmataceae) from raccoons (Procyon lotor). Int J Syst Evol Microbiol 2009; 58:2794-8. [PMID: 19060060 DOI: 10.1099/ijs.0.65836-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recently, a novel ehrlichial organism was isolated from a raccoon (Procyon lotor) and the isolate (RAC413) was infectious to two naïve raccoons but not laboratory mice, rats or rabbits. In this study, amplification and sequencing of four gene targets (16S rRNA gene, groESL, gltA and rpoB) confirmed that the novel ehrlichial organism was a member of the family Anaplasmataceae and was most closely related to, but distinct from, 'Candidatus Neoehrlichia mikurensis' TK4456(R) and IS58. RAC413 shared the highest sequence similarity with members of the genus Ehrlichia (94.2-95.1, 80.9-83.1, 67.9-71.9 and 39.9-40.7 % similarity for the 16S rRNA gene, groESL, gltA and rpoB, respectively). No sequence variation in three sequences (16S rRNA gene, groESL and gltA) was observed between the RAC413 isolate and five additional sequences amplified from blood of naturally infected raccoons from several geographically isolated populations in the south-eastern USA. Serum samples from four experimentally infected raccoons did not react to Ehrlichia canis, Ehrlichia chaffeensis, Anaplasma marginale or Anaplasma phagocytophilum antigens in an immunofluorescence assay or an Ehrlichia ewingii peptide in an ELISA format. On the basis of the distinctive molecular and serological characteristics and apparent host specificity of this ehrlichial organism, it is proposed that this organism be designated 'Candidatus Neoehrlichia lotoris' (reference strain RAC413).
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Affiliation(s)
- Michael J Yabsley
- Daniel B Warnell School of Forestry and Natural Resources, University of Georgia, Athens, GA 30602, USA.
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Adekambi T, Shinnick TM, Raoult D, Drancourt M. Complete rpoB gene sequencing as a suitable supplement to DNA-DNA hybridization for bacterial species and genus delineation. Int J Syst Evol Microbiol 2008; 58:1807-14. [DOI: 10.1099/ijs.0.65440-0] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Alexandrov ID, Alexandrova MV, Goryacheva II, Rochina NV, Shaikevich EV, Zakharov IA. Removing endosymbiotic Wolbachia specifically decreases lifespan of females and competitiveness in a laboratory strain of Drosophila melanogaster. RUSS J GENET+ 2007. [DOI: 10.1134/s1022795407100080] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Headley SA, Scorpio DG, Barat NC, Vidotto O, Dumler JS. Neorickettsia helminthoeca in dog, Brazil. Emerg Infect Dis 2006; 12:1303-4. [PMID: 16972361 PMCID: PMC3291224 DOI: 10.3201/eid1708.060130] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
| | - Diana G. Scorpio
- Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Nicole C. Barat
- Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | | - J. Stephen Dumler
- Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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16
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Abstract
Several organisms from a number of prokaryotic and eukaryotic groups have presented problems for systematists for a long time. Both phenotypic and genotypic methods for sorting out these relationships have been employed. There are limitations with each method when taken alone. Since the purpose of systematics is to determine the correct genealogical relationships among biological organisms, it is necessary to use all available means to arrive at consensus associations, and polyphasic taxonomy, which takes into consideration both methods, is a rational approach. In this short article, we provide a number of examples where polyphasic taxonomy is serving as the means of arriving at the desired consensus.
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17
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Fournier PE, Suhre K, Fournous G, Raoult D. Estimation of prokaryote genomic DNA G+C content by sequencing universally conserved genes. Int J Syst Evol Microbiol 2006; 56:1025-1029. [PMID: 16627649 DOI: 10.1099/ijs.0.63903-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Determination of the DNA G+C content of prokaryotic genomes using traditional methods is time-consuming and results may vary from laboratory to laboratory, depending on the technique used. We explored the possibility of extrapolating the genomic DNA G+C content of prokaryotes from gene sequences. For this, 127 universally conserved genes were studied from 50 prokaryotic genomes in the Clusters of Orthologous Groups database. Of these, 57 genes were present as a single copy in the genomes of 157 different prokaryote species available in GenBank. There was a strong correlation [coefficient of determination (r2) >95 %] between the DNA G+C contents of 20 genes and their corresponding genomes. For each of the 157 prokaryotic genomes studied, the DNA G+C content of the 20 genes was used to determine a 'calculated' genome DNA G+C content (CGC) and this value was compared with the 'real' genome DNA G+C content (RGC). In order to select the most suitable gene for the determination of CGC values, we compared the r2 and median mol% difference between CGC and RGC as well as the sensitivity of each gene to provide CGC values for prokaryotic genomes that differ by less than 5 mol% from their RGC. The highly conserved ftsY gene (median size 1144 nucleotides), a vertically inherited member of the GTPase superfamily, showed the highest r2 value of 0.98, the smallest median mol% difference between CGC and RGC of 1.06 and a sensitivity of 100 %. Using ftsY DNA G+C content values, the CGC values of 100 genomes not included in the calculation of r2 differed by less than 5 mol% from their RGC values. These data suggest that the genomic DNA G+C content of prokaryotes may be estimated easily and reliably from the ftsY gene sequence.
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Affiliation(s)
- Pierre-Edouard Fournier
- Information Génomique et Structurale, CNRS UPR2589, Case 934, 163 Avenue de Luminy, 13288 Marseille cedex 09, France
| | - Karsten Suhre
- Information Génomique et Structurale, CNRS UPR2589, Case 934, 163 Avenue de Luminy, 13288 Marseille cedex 09, France
| | - Ghislain Fournous
- Unité des rickettsies, IFR 48, CNRS UMR 6020, Faculté de Médecine, Université de la Méditerranée, 27 Boulevard Jean Moulin, 13385 Marseille cedex 05, France
| | - Didier Raoult
- Unité des rickettsies, IFR 48, CNRS UMR 6020, Faculté de Médecine, Université de la Méditerranée, 27 Boulevard Jean Moulin, 13385 Marseille cedex 05, France
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18
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Frutos R, Viari A, Ferraz C, Morgat A, Eychenié S, Kandassamy Y, Chantal I, Bensaid A, Coissac E, Vachiery N, Demaille J, Martinez D. Comparative genomic analysis of three strains of Ehrlichia ruminantium reveals an active process of genome size plasticity. J Bacteriol 2006; 188:2533-42. [PMID: 16547041 PMCID: PMC1428390 DOI: 10.1128/jb.188.7.2533-2542.2006] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ehrlichia ruminantium is the causative agent of heartwater, a major tick-borne disease of livestock in Africa that has been introduced in the Caribbean and is threatening to emerge and spread on the American mainland. We sequenced the complete genomes of two strains of E. ruminantium of differing phenotypes, strains Gardel (Erga; 1,499,920 bp), from the island of Guadeloupe, and Welgevonden (Erwe; 1,512,977 bp), originating in South Africa and maintained in Guadeloupe in a different cell environment. Comparative genomic analysis of these two strains was performed with the recently published parent strain of Erwe (Erwo) and other Rickettsiales (Anaplasma, Wolbachia, and Rickettsia spp.). Gene order is highly conserved between the E. ruminantium strains and with A. marginale. In contrast, there is very little conservation of gene order with members of the Rickettsiaceae. However, gene order may be locally conserved, as illustrated by the tuf operons. Eighteen truncated protein-encoding sequences (CDSs) differentiate Erga from Erwe/Erwo, whereas four other truncated CDSs differentiate Erwe from Erwo. Moreover, E. ruminantium displays the lowest coding ratio observed among bacteria due to unusually long intergenic regions. This is related to an active process of genome expansion/contraction targeted at tandem repeats in noncoding regions and based on the addition or removal of ca. 150-bp tandem units. This process seems to be specific to E. ruminantium and is not observed in the other Rickettsiales.
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Affiliation(s)
- Roger Frutos
- CIRAD TA30/G, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France.
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19
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Gupta RS. Protein signatures distinctive of alpha proteobacteria and its subgroups and a model for alpha-proteobacterial evolution. Crit Rev Microbiol 2005; 31:101-35. [PMID: 15986834 DOI: 10.1080/10408410590922393] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Alpha (alpha) proteobacteria comprise a large and metabolically diverse group. No biochemical or molecular feature is presently known that can distinguish these bacteria from other groups. The evolutionary relationships among this group, which includes numerous pathogens and agriculturally important microbes, are also not understood. Shared conserved inserts and deletions (i.e., indels or signatures) in molecular sequences provide a powerful means for identification of different groups in clear terms, and for evolutionary studies (see www.bacterialphylogeny.com). This review describes, for the first time, a large number of conserved indels in broadly distributed proteins that are distinctive and unifying characteristics of either all alpha-proteobacteria, or many of its constituent subgroups (i.e., orders, families, etc.). These signatures were identified by systematic analyses of proteins found in the Rickettsia prowazekii (RP) genome. Conserved indels that are unique to alpha-proteobacteria are present in the following proteins: Cytochrome c oxidase assembly protein Ctag, PurC, DnaB, ATP synthase alpha-subunit, exonuclease VII, prolipoprotein phosphatidylglycerol transferase, RP-400, FtsK, puruvate phosphate dikinase, cytochrome b, MutY, and homoserine dehydrogenase. The signatures in succinyl-CoA synthetase, cytochrome oxidase I, alanyl-tRNA synthetase, and MutS proteins are found in all alpha-proteobacteria, except the Rickettsiales, indicating that this group has diverged prior to the introduction of these signatures. A number of proteins contain conserved indels that are specific for Rickettsiales (XerD integrase and leucine aminopeptidase), Rickettsiaceae (Mfd, ribosomal protein L19, FtsZ, Sigma 70 and exonuclease VII), or Anaplasmataceae (Tgt and RP-314), and they distinguish these groups from all others. Signatures in DnaA, RP-057, and DNA ligase A are commonly shared by various Rhizobiales, Rhodobacterales, and Caulobacter, suggesting that these groups shared a common ancestor exclusive of other alpha-proteobacteria. A specific relationship between Rhodobacterales and Caulobacter is indicated by a large insert in the Asn-Gln amidotransferase. The Rhizobiales group of species are distinguished from others by a large insert in the Trp-tRNA synthetase. Signature sequences in a number of other proteins (viz. oxoglutarate dehydogenase, succinyl-CoA synthase, LytB, DNA gyrase A, LepA, and Ser-tRNA synthetase) serve to distinguish the Rhizobiaceae, Brucellaceae, and Phyllobacteriaceae families from Bradyrhizobiaceae and Methylobacteriaceae. Based on the distribution patterns of these signatures, it is now possible to logically deduce a model for the branching order among alpha-proteobacteria, which is as follows: Rickettsiales --> Rhodospirillales-Sphingomonadales --> Rhodobacterales-Caulobacterales --> Rhizobiales (Rhizobiaceaea-Brucellaceae-Phyllobacteriaceae, and Bradyrhizobiaceae). The deduced branching order is also consistent with the topologies in the 16 rRNA and other phylogenetic trees. Signature sequences in a number of other proteins provide evidence that alpha-proteobacteria is a late branching taxa within Bacteria, which branched after the delta,epsilon-subdivisions but prior to the beta,gamma-proteobacteria. The shared presence of many of these signatures in the mitochondrial (eukaryotic) homologs also provides evidence of the alpha-proteobacterial ancestry of mitochondria.
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Affiliation(s)
- Radhey S Gupta
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
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20
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de la Fuente J, Massung RF, Wong SJ, Chu FK, Lutz H, Meli M, von Loewenich FD, Grzeszczuk A, Torina A, Caracappa S, Mangold AJ, Naranjo V, Stuen S, Kocan KM. Sequence analysis of the msp4 gene of Anaplasma phagocytophilum strains. J Clin Microbiol 2005; 43:1309-17. [PMID: 15750101 PMCID: PMC1081214 DOI: 10.1128/jcm.43.3.1309-1317.2005] [Citation(s) in RCA: 162] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The causative agent of human granulocytic ehrlichiosis was recently reclassified as Anaplasma phagocytophilum, unifying previously described bacteria that cause disease in humans, horses, dogs, and ruminants. For the characterization of genetic heterogeneity in this species, the homologue of Anaplasma marginale major surface protein 4 gene (msp4) was identified, and the coding region was PCR amplified and sequenced from a variety of sources, including 50 samples from the United States, Germany, Poland, Norway, Italy, and Switzerland and 4 samples of A. phagocytophilum-like organisms obtained from white-tailed deer in the United States. Sequence variation between strains of A. phagocytophilum (90 to 100% identity at the nucleotide level and 92 to 100% similarity at the protein level) was higher than in A. marginale. Phylogenetic analyses of msp4 sequences did not provide phylogeographic information but did differentiate strains of A. phagocytophilum obtained from ruminants from those obtained from humans, dogs, and horses. The sequence analysis of the recently discovered A. phagocytophilum msp2 gene corroborated these results. The results reported here suggest that although A. phagocytophilum-like organisms from white-tailed deer may be closely related to A. phagocytophilum, they could be more diverse. These results suggest that A. phagocytophilum strains from ruminants could share some common characteristics, including reservoirs and pathogenicity, which may be different from strains that infect humans.
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Affiliation(s)
- José de la Fuente
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK 74078, USA.
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21
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Abstract
Technological innovations in the detection and identification of microorganisms using molecular techniques such as polymerase chain reaction (PCR) have ushered in a new era with respect to diagnostic microbiology. PCR using universal or specific primers followed by identification of amplified product, mainly by sequencing, has enabled the rapid identification of cultured or uncultured bacteria. Thus, PCR may allow quick diagnosis of infections caused by fastidious pathogens for which culture could be extremely difficult. However, several pitfalls, such as false positives, have been observed with PCR, underlining the necessity to interpret the results obtained with caution. At present, certain improvements in the molecular genetic methods may be helpful for the diagnosis of infectious diseases. Indeed, the recent development of bacterial genome sequencing has provided an important source of potential targets for PCR, allowing rational choice of primers for diagnosis and genotyping. In addition, the development of new techniques such as real-time PCR offers several advantages in comparison to conventional PCR, including speed, simplicity, reproducibility, quantitative capability and low risk of contamination. Herein, we review the general principles of PCR-based diagnosis and molecular genetic methods for the diagnosis of several hard-to-culture bacteria, such as Rickettsia spp., Ehrlichia spp., Coxiella burnetii, Bartonella spp., Tropheryma whipplei and Yersinia pestis.
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Affiliation(s)
- Florence Fenollar
- Unité des Rickettsies, Faculté de Médecine, Université de la Méditerranée, Marseille, France
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22
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Fry AJ, Palmer MR, Rand DM. Variable fitness effects of Wolbachia infection in Drosophila melanogaster. Heredity (Edinb) 2004; 93:379-89. [PMID: 15305172 DOI: 10.1038/sj.hdy.6800514] [Citation(s) in RCA: 151] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Maternally inherited Wolbachia bacteria are extremely widespread among insects and their presence is usually associated with parasitic modifications of host fitness. Wolbachia pipientis infects Drosophila melanogaster populations from all continents, but their persistence in this species occurs despite any strong parasitic effects. Here, we have investigated the symbiosis between Wolbachia and D. melanogaster and found that Wolbachia infection can have significant survival and fecundity effects. Relative to uninfected flies, infected females from three fly strains showed enhanced survival or fecundity associated with Wolbachia infection, one strain showed both and one strain responded positively to Wolbachia removal. We found no difference in egg hatch rates (cytoplasmic incompatibility) for crosses between infected males and uninfected females, although there were fecundity differences. Females from this cross consistently produced fewer eggs than infected females and these fecundity differences could promote the spread of infection just like cytoplasmic incompatibility. More surprising, we found that infected females often had the greatest fecundity when mated to uninfected males. This could also promote the spread of Wolbachia infection, though here the fitness benefits would also help to spread infection when Wolbachia are rare. We suggest that variable fitness effects, in both sexes, and which interact strongly with the genetic background of the host, could increase cytoplasmic drive rates in some genotypes and help explain the widespread persistence of Wolbachia bacteria in D. melanogaster populations. These interactions may further explain why many D. melanogaster populations are polymorphic for Wolbachia infection. We discuss our results in the context of host-symbiont co-evolution.
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Affiliation(s)
- A J Fry
- Department of Ecology and Evolutionary Biology, Box G-W, Brown University, Providence, RI 02912, USA.
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23
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Korczak B, Christensen H, Emler S, Frey J, Kuhnert P. Phylogeny of the family Pasteurellaceae based on rpoB sequences. Int J Syst Evol Microbiol 2004; 54:1393-1399. [PMID: 15280320 DOI: 10.1099/ijs.0.03043-0] [Citation(s) in RCA: 147] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Sequences of the gene encoding theβ-subunit of the RNA polymerase (rpoB) were used to delineate the phylogeny of the familyPasteurellaceae. A total of 72 strains, including the type strains of the major described species as well as selected field isolates, were included in the study. Selection of universalrpoB-derived primers for the family allowed straightforward amplification and sequencing of a 560 bp fragment of therpoBgene. In parallel, 16S rDNA was sequenced from all strains. The phylogenetic tree obtained with therpoBsequences reflected the major branches of the tree obtained with the 16S rDNA, especially at the genus level. Only a few discrepancies between the trees were observed. In certain cases therpoBphylogeny was in better agreement with DNA–DNA hybridization studies than the phylogeny derived from 16S rDNA. TherpoBgene is strongly conserved within the various species of the family ofPasteurellaceae. Hence,rpoBgene sequence analysis in conjunction with 16S rDNA sequencing is a valuable tool for phylogenetic studies of thePasteurellaceaeand may also prove useful for reorganizing the current taxonomy of this bacterial family.
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Affiliation(s)
- Bożena Korczak
- Institute of Veterinary Bacteriology, University of Bern, CH-3012 Bern, Switzerland
| | - Henrik Christensen
- Department of Veterinary Microbiology, The Royal Veterinary and Agricultural University, DK-1870 Frederiksberg C, Denmark
| | - Stefan Emler
- SmartGene GmbH, PSE-C EPFL-Ecublens, CH-1015 Lausanne, Switzerland
| | - Joachim Frey
- Institute of Veterinary Bacteriology, University of Bern, CH-3012 Bern, Switzerland
| | - Peter Kuhnert
- Institute of Veterinary Bacteriology, University of Bern, CH-3012 Bern, Switzerland
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24
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Drancourt M, Roux V, Fournier PE, Raoult D. rpoB gene sequence-based identification of aerobic Gram-positive cocci of the genera Streptococcus, Enterococcus, Gemella, Abiotrophia, and Granulicatella. J Clin Microbiol 2004; 42:497-504. [PMID: 14766807 PMCID: PMC344509 DOI: 10.1128/jcm.42.2.497-504.2004] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We developed a new molecular tool based on rpoB gene (encoding the beta subunit of RNA polymerase) sequencing to identify streptococci. We first sequenced the complete rpoB gene for Streptococcus anginosus, S. equinus, and Abiotrophia defectiva. Sequences were aligned with these of S. pyogenes, S. agalactiae, and S. pneumoniae available in GenBank. Using an in-house analysis program (SVARAP), we identified a 740-bp variable region surrounded by conserved, 20-bp zones and, by using these conserved zones as PCR primer targets, we amplified and sequenced this variable region in an additional 30 Streptococcus, Enterococcus, Gemella, Granulicatella, and Abiotrophia species. This region exhibited 71.2 to 99.3% interspecies homology. We therefore applied our identification system by PCR amplification and sequencing to a collection of 102 streptococci and 60 bacterial isolates belonging to other genera. Amplicons were obtained in streptococci and Bacillus cereus, and sequencing allowed us to make a correct identification of streptococci. Molecular signatures were determined for the discrimination of closely related species within the S. pneumoniae-S. oralis-S. mitis group and the S. agalactiae-S. difficile group. These signatures allowed us to design a S. pneumoniae-specific PCR and sequencing primer pair.
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Affiliation(s)
- Michel Drancourt
- Unité des Rickettsies, IFR 48, Faculté de Médecine, Université de la Méditerranée, Marseille, France
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