Mycoplasma mycoides subsp. mycoides small-colony type (SC), the aetiological agent of contagious bovine pleuropneumonia (CBPP), can be grouped into two major, epidemiologically distinct, clusters. One cluster contains strains isolated from different European countries since 1980 and a second cluster contains African and Australian strains collected over the last 50 years. Genetic analysis of representative strains from the two clusters revealed a genomic segment of 8·84 kb, located close to a copy of IS1296, which is present in all strains of the African cluster but lacking in all strains of the European cluster. This segment contains a copy of IS1634, a gene for a potential lipoprotein, lppB, open reading frames encoding a putative surface-located membrane protein and a hypothetical proline-rich membrane protein, and two open reading frames showing similarity to putative ABC transporters. The product of the lppB gene, lipoprotein B (LppB), has an apparent molecular mass of 70 kDa and was shown to be surface located. It is detected with monospecific antibodies in all strains of the African cluster tested, but not in European-cluster strains. DNA sequence analysis of the splicing site at which European strains differ from African-cluster strains by the lack of the 8·84 kb segment showed that the European cluster has arisen by deletion from a strain of the African cluster. Hence, M. mycoides subsp. mycoides SC strains isolated in different European countries from the newly reemerging outbreaks of CBPP, which occurred after the eradication of the epizootic in Europe in the middle of the 20th century, represent a phylogenetically newer cluster that has been derived from a strain of the older cluster of M. mycoides subsp. mycoides SC which is still endemic on the African continent.
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1 November 2012 in International Journal of Medical Microbiology
The temporal and spatial diversity of Coxiella burnetii genotypes associated with human and animal disease in Portugal was analysed using a 6-locus multiple-locus variable-number tandem repeat analysis (MLVA) and a 10-locus multi-spacer sequence typing (MST) panel. Fifteen cultured C. burnetii isolates from 13 Q fever patients and a stillborn goat and 6 additional PCR-positive ruminant tissue samples obtained during 2006-2011 were included in this study. Seven MLVA genotypes (types S-Y) were obtained, including 4 new MLVA types (U, V, W, and X), all corresponding to 3 MST profiles (types 4, 8, and 13) previously reported from France and Spain. MLVA types U-Y, all belonging to MST type 4, were found in acute Q fever patients from the districts of Évora, Faro, Lisbon, and Setúbal. Different MLVA types were associated with goats from Castelo Branco district (S) and chronic Q fever patients from both Castelo Branco and Lisboa districts (S and T), matching with MST types 13 and 8, respectively. In conclusion, a genotypic diversity of C. burnetii consistent with a non-outbreak situation was identified. The involvement of different genotypes in acute and chronic Q fever was found, linking one of the chronic genotypes to goats from the eastern region of the country.