151
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Zumárraga MJ, Meikle V, Bernardelli A, Abdala A, Tarabla H, Romano MI, Cataldi A. Use of touch-down polymerase chain reaction to enhance the sensitivity of Mycobacterium bovis detection. J Vet Diagn Invest 2005; 17:232-8. [PMID: 15945378 DOI: 10.1177/104063870501700303] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The confirmatory diagnosis of Mycobacterium bovis (M. bovis) in animal samples is carried out by culture in Stonebrink media. However, culture is very slow because of the extremely long duplication time of the bacillus and difficult because of the scarcity of bacilli in diagnostic samples. This study describes the development of a single-tube touch-down polymerase chain reaction (PCR) protocol for the detection of M. bovis using primers that target the IS6110 element. Spiked water and milk as well as routine diagnostic samples (milk and nasal swabs) from M. bovis-positive cattle were tested. This protocol allows the rapid and sensitive detection of M. bovis in bovine samples by enhancing the sensitivity of standard PCR amplification.
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Affiliation(s)
- Martín J Zumárraga
- Instituto de Biotecnología, CICVyA/INTA, Los Reseros y las Cabañas, 1712 Castelar, Argentina
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152
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Amadio A, Romano MI, Bigi F, Etchechoury I, Kubica T, Niemann S, Cataldi A, Caimi K. Identification and characterization of genomic variations between Mycobacterium bovis and M. tuberculosis H37Rv. J Clin Microbiol 2005; 43:2481-4. [PMID: 15872289 PMCID: PMC1153726 DOI: 10.1128/jcm.43.5.2481-2484.2005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Genetic differences between Mycobacterium bovis and M. tuberculosis were identified. We found (i) a deletion of Rv3479 specific to M. bovis, (ii) that the rpfA gene is shortened to various extents in M. bovis, and (iii) an insertion in Rv0648 and a duplication of lppA common in M. tuberculosis complex isolates.
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Affiliation(s)
- Ariel Amadio
- Institute of Microbiology and Agricultural Zoology, CICVyA/INTA, Castelar, Argentina
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153
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Bigi F, Garcia-Pelayo MC, Nuñez-García J, Peralta A, Caimi KC, Golby P, Hinds J, Cataldi A, Gordon SV, Romano MI. Identification of genetic markers forMycobacterium pinnipediithrough genome analysis. FEMS Microbiol Lett 2005; 248:147-52. [PMID: 15979818 DOI: 10.1016/j.femsle.2005.05.034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2005] [Revised: 03/15/2005] [Accepted: 05/15/2005] [Indexed: 10/25/2022] Open
Abstract
Tuberculosis in seals is caused by Mycobacterium pinnipedii, a member of the Mycobacterium tuberculosis complex. In this study, we evaluated the extent of genetic variability among Mycobacterium bovis and M. pinnipedii by microarray-based comparative genomics. We identified two deletions that are exclusive to M. pinnipedii: PiD1 that removes the orthologues of the M. tuberculosis genes Rv3530c and Rv3531c, and PiD2 that encompasses genes Rv1977 and Rv1978. Interestingly, a deletion overlapping the previously described RD2 region was identified in some isolates of Mycobacterium microti and further characterised.
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Affiliation(s)
- Fabiana Bigi
- Institute of Biotechnology, CICVyA-INTA, 1712 Castelar, Argentina.
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154
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Abstract
This article introduces the tools and terminology used for the classification of specific isolates of the Mycobacterium tuberculosis complex (MTC). The utility of these tools and terminology is illustrated by discussing work from independent laboratories that have established a genome-based phylogeny for the MTC. It considers the use of these markers to distinguish atypical isolates not conforming to attributes of traditional MTC members. Finally, it discusses the current genomic evidence regarding the origin and evolution of M. tuberculosis in the context of its relevance for tuberculosis control in humans and other mammalian hosts.
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Affiliation(s)
- Serge Mostowy
- McGill University Health Centre, 1650 Cedar Avenue, Montreal, QC H3G 1A4, Canada
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155
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Okazaki T, Ebihara S, Takahashi H, Asada M, Sato A, Seki M, Ohto H, Sasaki H. Multiplex PCR-identified cutaneous tuberculosis evoked by Mycobacterium bovis BCG vaccination in a healthy baby. J Clin Microbiol 2005; 43:523-5. [PMID: 15635035 PMCID: PMC540101 DOI: 10.1128/jcm.43.1.523-525.2005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This is the first identified case of Mycobacterium bovis bacillus Calmette-Guerin (BCG)-derived cutaneous tuberculosis that localizes at a place different from the vaccination site in hosts without immune deficiency. A healthy baby with a developing abscess is described. A multiplex PCR identified the abscess as originating from M. bovis BCG Tokyo 172.
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Affiliation(s)
- Tatsuma Okazaki
- Department of Geriatric and Respiratory Medicine, Tohoku University School of Medicine, Seiryo-machi 1-1, Aoba-ku, Sendai 980-8574, Japan.
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156
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Brudey K, Gutierrez MC, Vincent V, Parsons LM, Salfinger M, Rastogi N, Sola C. Mycobacterium africanum genotyping using novel spacer oligonucleotides in the direct repeat locus. J Clin Microbiol 2005; 42:5053-7. [PMID: 15528695 PMCID: PMC525283 DOI: 10.1128/jcm.42.11.5053-5057.2004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
This study involves a first evaluation of 25 novel spacer oligonucleotides in addition to the 43 routine spacers for molecular characterization of a panel of 65 isolates of tubercle bacilli from different geographic origins that were initially classified as Mycobacterium africanum based on phenotypic characters. The 68-spacer format defined four additional patterns, and three groups were identified. The relatively homogeneous groups A1 and A2 included strains from West Africa, and A3-1 included strains from East Africa. The presence of deletion region RD9 confirmed the reclassification of the M. africanum subtype II spoligopattern within group A3-1 as Mycobacterium tuberculosis. These isolates may represent a diverging branch of M. tuberculosis in Africa. The use of new spacers also suggested an undergoing evolution of M. africanum subtype I in West Africa. Our results showed that the strain differentiation within the M. tuberculosis complex is improved by using novel spacers, and extensive studies using new-generation spoligotyping may be helpful to better understand the evolution of M. africanum.
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Affiliation(s)
- Karine Brudey
- Unité de la Tuberculose et des Mycobactéries, Institut Pasteur de Guadeloupe, Pointe-à-Pitre, Guadeloupe, France
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157
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Chimara E, Ferrazoli L, Leão SC. Mycobacterium tuberculosis complex differentiation using gyrB-restriction fragment length polymorphism analysis. Mem Inst Oswaldo Cruz 2005; 99:745-8. [PMID: 15654432 DOI: 10.1590/s0074-02762004000700014] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Mycobacterium tuberculosis complex (MTBC) members are causative agents of human and animal tuberculosis. Differentiation of MTBC members is required for appropriate treatment of individual patients and for epidemiological purposes. Strains from six MTBC species -- M. tuberculosis, M. bovis subsp. bovis, M. bovis BCG, M. africanum, M. pinnipedii, and "M. canetti" -- were studied using gyrB-restriction fragment length polymorphism (gyrB-RFLP) analysis. A table was elaborated, based on observed restriction patterns and published gyrB sequences. To evaluate applicability of gyrB-RFLP at Instituto Adolfo Lutz, Sao Paulo, Mycobacterial Reference Laboratory, 311 MTBC clinical isolates, previously identified using traditional methods as M. tuberculosis (306), M. bovis (3), and M. bovis BCG (2), were analyzed by gyrB-RFLP. All isolates were correctly identified by the molecular method, but no distinction between M. bovis and M. bovis BCG was obtained. Differentiation of M. tuberculosis and M. bovis is of utmost importance, because they require different treatment schedules. In conclusion, gyrB-RFLP is accurate and easy-to-perform, with potential to reduce time needed for conventional differentiation methods. However, application for epidemiological studies remains limited, because it cannot differentiate M. tuberculosis from M. africanum subtype II, and "M. canetti", M. africanum subtype I from M. pinnipedii, and. M. bovis from M. bovis BCG.
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Affiliation(s)
- Erica Chimara
- Setor de Micobactérias, Seção de Bacteriologia, Instituto Adolfo Lutz, Av. Dr. Arnaldo 355, 01246-902 São Paulo, SP, Brazil.
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158
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Garcia-Pelayo MC, Caimi KC, Inwald JK, Hinds J, Bigi F, Romano MI, van Soolingen D, Hewinson RG, Cataldi A, Gordon SV. Microarray analysis of Mycobacterium microti reveals deletion of genes encoding PE-PPE proteins and ESAT-6 family antigens. Tuberculosis (Edinb) 2004; 84:159-66. [PMID: 15207485 DOI: 10.1016/j.tube.2003.12.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/23/2003] [Indexed: 10/26/2022]
Abstract
Mycobacterium microti is the agent of tuberculosis in wild voles and has been used as a live vaccine against tuberculosis in man and cattle. To explore the M. microti genome in greater detail, we used a M. tuberculosis H37Rv genomic DNA microarray to detect gene deletions among M. microti isolates. A number of deletions were identified that correlated with those described previously (Infect. Immun. 70 (2002) 5568) but a novel M. microti deletion was also found (MiD4) which removes 5 genes that code for ESAT-6 family antigens and PE-PPE proteins. Southern blot experiments showed that this region was also deleted from M. pinnipedii, a mycobacterium isolated from seals that is closely related to M. microti. Genes encoding ESAT-6 antigens and PE-PPE proteins appear to be frequently deleted from M. microti, and the implications of this are discussed.
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Affiliation(s)
- M Carmen Garcia-Pelayo
- Veterinary Laboratories Agency (Weybridge), Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK
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159
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Herdman AV, Steele JCH. The new mycobacterial species—emerging or newly distinguished pathogens. Clin Lab Med 2004; 24:651-90, vi. [PMID: 15325060 DOI: 10.1016/j.cll.2004.05.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Diseases due to nontuberculous mycobacteria are increasing in frequency, especially in patients with compromised immunity. A number of "new" mycobacterial species have been described in the last decade, largely as the result of the use of new tools to identify previously unrecognized mycobacteria found in the environment and in clinical specimens. This article reviews many of these potentially pathogenic organisms, summarizing what is known regarding their phenotypic and genotypic characterization, antimicrobial susceptibility, and clinical significance.
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Affiliation(s)
- Anne V Herdman
- Department of Pathology, Medical College of Georgia, 1120 15th Street, Augusta, GA 30912, USA
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160
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Mostowy S, Onipede A, Gagneux S, Niemann S, Kremer K, Desmond EP, Kato-Maeda M, Behr M. Genomic analysis distinguishes Mycobacterium africanum. J Clin Microbiol 2004; 42:3594-9. [PMID: 15297503 PMCID: PMC497617 DOI: 10.1128/jcm.42.8.3594-3599.2004] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2004] [Revised: 04/28/2004] [Accepted: 05/07/2004] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium africanum is thought to comprise a unique species within the Mycobacterium tuberculosis complex. M. africanum has traditionally been identified by phenotypic criteria, occupying an intermediate position between M. tuberculosis and M. bovis according to biochemical characteristics. Although M. africanum isolates present near-identical sequence homology to other species of the M. tuberculosis complex, several studies have uncovered large genomic regions variably deleted from certain M. africanum isolates. To further investigate the genomic characteristics of organisms characterized as M. africanum, the DNA content of 12 isolates was interrogated by using Affymetrix GeneChip. Analysis revealed genomic regions of M. tuberculosis deleted from all isolates of putative diagnostic and biological consequence. The distribution of deleted sequences suggests that M. africanum subtype II isolates are situated among strains of "modern" M. tuberculosis. In contrast, other M. africanum isolates (subtype I) constitute two distinct evolutionary branches within the M. tuberculosis complex. To test for an association between deleted sequences and biochemical attributes used for speciation, a phenotypically diverse panel of "M. africanum-like" isolates from Guinea-Bissau was tested for these deletions. These isolates clustered together within one of the M. africanum subtype I branches, irrespective of phenotype. These results indicate that convergent biochemical profiles can be independently obtained for M. tuberculosis complex members, challenging the traditional approach to M. tuberculosis complex speciation. Furthermore, the genomic results suggest a rational framework for defining M. africanum and provide tools to accurately assess its prevalence in clinical specimens.
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161
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Marmiesse M, Brodin P, Buchrieser C, Gutierrez C, Simoes N, Vincent V, Glaser P, Cole ST, Brosch R. Macro-array and bioinformatic analyses reveal mycobacterial 'core' genes, variation in the ESAT-6 gene family and new phylogenetic markers for the Mycobacterium tuberculosis complex. MICROBIOLOGY-SGM 2004; 150:483-496. [PMID: 14766927 DOI: 10.1099/mic.0.26662-0] [Citation(s) in RCA: 144] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
To better understand the biology and the virulence determinants of the two major mycobacterial human pathogens Mycobacterium tuberculosis and Mycobacterium leprae, their genome sequences have been determined recently. In silico comparisons revealed that among the 1439 genes common to both M. tuberculosis and M. leprae, 219 genes code for proteins that show no similarity with proteins from other organisms. Therefore, the latter 'core' genes could be specific for mycobacteria or even for the intracellular mycobacterial pathogens. To obtain more information as to whether these genes really were mycobacteria-specific, they were included in a focused macro-array, which also contained genes from previously defined regions of difference (RD) known to be absent from Mycobacterium bovis BCG relative to M. tuberculosis. Hybridization of DNA from 40 strains of the M. tuberculosis complex and in silico comparison of these genes with the near-complete genome sequences from Mycobacterium avium, Mycobacterium marinum and Mycobacterium smegmatis were undertaken to answer this question. The results showed that among the 219 conserved genes, very few were not present in all the strains tested. Some of these missing genes code for proteins of the ESAT-6 family, a group of highly immunogenic small proteins whose presence and number is variable among the genomically highly conserved members of the M. tuberculosis complex. Indeed, the results suggest that, with few exceptions, the 'core' genes conserved among M. tuberculosis H37Rv and M. leprae are also highly conserved among other mycobacterial strains, which makes them interesting potential targets for developing new specific anti-mycobacterial drugs. In contrast, the genes from RD regions showed great variability among certain members of the M. tuberculosis complex, and some new specific deletions in Mycobacterium canettii, Mycobacterium microti and seal isolates were identified and further characterized during this study. Together with the distribution of a particular 6 or 7 bp micro-deletion in the gene encoding the polyketide synthase pks15/1, these results confirm and further extend the revised phylogenetic model for the M. tuberculosis complex recently presented.
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Affiliation(s)
- Magali Marmiesse
- Unité de Génétique Moléculaire Bactérienne, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Priscille Brodin
- Unité de Génétique Moléculaire Bactérienne, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Carmen Buchrieser
- Laboratoire de Génomique des Micro-organismes Pathogènes, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Christina Gutierrez
- Centre National de Référence des Mycobactéries, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Nathalie Simoes
- Laboratoire de Génomique des Micro-organismes Pathogènes, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Veronique Vincent
- Centre National de Référence des Mycobactéries, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Philippe Glaser
- Laboratoire de Génomique des Micro-organismes Pathogènes, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Stewart T Cole
- Unité de Génétique Moléculaire Bactérienne, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
| | - Roland Brosch
- Unité de Génétique Moléculaire Bactérienne, Institut Pasteur, 25-28 rue du Docteur Roux, 75724 Paris Cedex 15, France
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162
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Viana-Niero C, de Haas PE, van Soolingen D, Leão SC. Analysis of genetic polymorphisms affecting the four phospholipase C (plc) genes in Mycobacterium tuberculosis complex clinical isolates. Microbiology (Reading) 2004; 150:967-978. [PMID: 15073306 DOI: 10.1099/mic.0.26778-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The Mycobacterium tuberculosis genome contains four highly related genes which present significant similarity to Pseudomonas aeruginosa genes encoding phospholipase C enzymes. Three of these genes, plcA, plcB and plcC, are organized in tandem (locus plcABC). The fourth gene, plcD, is located in a different region. This study investigates variations in plcABC and plcD genes in clinical isolates of M. tuberculosis, Mycobacterium africanum and ‘Mycobacterium canettii’. Genetic polymorphisms were examined by PCR, Southern blot hybridization, sequence analysis and RT-PCR. Seven M. tuberculosis isolates contain insertions of IS6110 elements within plcA, plcC or plcD. In 19 of 25 M. tuberculosis isolates examined, genomic deletions were identified, resulting in loss of parts of genes or complete genes from the plcABC and/or plcD loci. Partial plcD deletion was observed in one M. africanum isolate. In each case, deletions were associated with the presence of a copy of the IS6110 element and in all occurrences IS6110 was transposed in the same orientation. A mechanism of deletion resulting from homologous recombination of two copies of IS6110 was recognized in a group of genetically related M. tuberculosis isolates. Five M. tuberculosis isolates presented major polymorphisms in the plcABC and plcD regions, along with loss of expression competence that affected all four plc genes. Phospholipase C is a well-known bacterial virulence factor. The precise role of phospholipase C in the pathogenicity of M. tuberculosis is unknown, but considering the potential importance that the plc genes may have in the virulence of the tubercle bacillus, the study of isolates cultured from patients with active tuberculosis bearing genetic variations affecting these genes may provide insights into the significance of phospholipase C enzymes for tuberculosis pathogenicity.
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Affiliation(s)
- C Viana-Niero
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo - Escola Paulista de Medicina (UNIFESP-EPM), Rua Botucatu, 862 3° andar, 04023-062, São Paulo, Brazil
| | - P E de Haas
- Diagnostic Laboratory of Infectious Diseases and Perinatal Screening, National Institute of Public Health and the Environment (RIVM), PO Box 1, 3720 BA, The Netherlands
| | - D van Soolingen
- Diagnostic Laboratory of Infectious Diseases and Perinatal Screening, National Institute of Public Health and the Environment (RIVM), PO Box 1, 3720 BA, The Netherlands
| | - S C Leão
- Departamento de Microbiologia, Imunologia e Parasitologia, Universidade Federal de São Paulo - Escola Paulista de Medicina (UNIFESP-EPM), Rua Botucatu, 862 3° andar, 04023-062, São Paulo, Brazil
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163
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Lantos A, Niemann S, Mezõsi L, Sós E, Erdélyi K, Dávid S, Parsons LM, Kubica T, Rüsch-Gerdes S, Somoskövi A. Pulmonary tuberculosis due to Mycobacterium bovis subsp. caprae in captive Siberian tiger. Emerg Infect Dis 2004; 9:1462-4. [PMID: 14718093 PMCID: PMC3035528 DOI: 10.3201/eid0911.030297] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We report the first case of pulmonary tuberculosis caused by Mycobacterium bovis subsp. caprae in a captive Siberian tiger, an endangered feline. The pathogen was isolated from a tracheal aspirate obtained by bronchoscopy. This procedure provided a reliable in vivo diagnostic method in conjunction with conventional and molecular tests for the detection of mycobacteria.
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164
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Mostowy S, Cousins D, Behr MA. Genomic interrogation of the dassie bacillus reveals it as a unique RD1 mutant within the Mycobacterium tuberculosis complex. J Bacteriol 2004; 186:104-9. [PMID: 14679230 PMCID: PMC303463 DOI: 10.1128/jb.186.1.104-109.2003] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite their remarkable genetic homology, members of the Mycobacterium tuberculosis complex express very different phenotypes, most notably in their spectra of clinical presentation. For example, M. tuberculosis is regarded as pathogenic to humans, whereas members having deleted RD1, such as Mycobacterium microti and Mycobacterium bovis BCG, are not. The dassie bacillus, an infrequent variant of the M. tuberculosis complex characterized as being most similar to M. microti, is the causative agent of tuberculosis (TB) in the dassie (Procavia capensis). Intriguingly, the dassie bacillus is not pathogenic to rabbits or guinea pigs and has never been documented to infect humans. Although it was identified more than a half-century ago, the reasons behind its attenuation are unknown. Because large sequence polymorphisms have presented themselves as the most obvious genomic distinction among members of the M. tuberculosis complex, the DNA content of the dassie bacillus was interrogated by Affymetrix GeneChip to identify regions that are absent from it but present in M. tuberculosis H37Rv. Comparison has led to the identification of nine regions of difference (RD), five of which are shared with M. microti (RDs 3, 7, 8, 9, and 10). Although the dassie bacillus does not share the other documented deletions in M. microti (RD1(mic), RD5(mic), MID1, MID2, and MID3), it has endured unique deletions in the regions of RD1, RD5, N-RD25, and Rv3081-Rv3082c (virS). RD1(das), affecting only Rv3874-Rv3877, is the smallest natural deletion of the RD1 region uncovered and points to genes within this region that are likely implicated in virulence. Newfound deletions from the dassie bacillus are discussed in relation to their evolutionary and biological significance.
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Affiliation(s)
- Serge Mostowy
- McGill University Health Centre, Montreal, Canada H3G 1A4
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