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- Abu Al-Soud, Waleed, et al.
(författare)
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Assessment of PCR-DGGE for the identification of diverse Helicobacter species, and application to faecal samples from zoo animals to determine Helicobacter prevalence.
- 2003
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Ingår i: Journal of Medical Microbiology. - : Microbiology Society. - 0022-2615 .- 1473-5644. ; 52:9, s. 765-771
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Tidskriftsartikel (refereegranskat)abstract
- Helicobacter species are fastidious bacterial pathogens that are difficult to culture by standard methods. A PCR-denaturing gradient gel electrophoresis (PCR-DGGE) technique for detection and identification of different Helicobacter species was developed and evaluated. The method involves PCR detection of Helicobacter DNA by genus-specific primers that target 16S rDNA and subsequent differentiation of Helicobacter PCR products by use of DGGE. Strains are identified by comparing mobilities of unknown samples to those determined for reference strains; sequence analysis can also be performed on purified amplicons. Sixteen DGGE profiles were derived from 44 type and reference strains of 20 Helicobacter species, indicating the potential of this approach for resolving infection of a single host by multiple Helicobacter species. Some more highly related species were not differentiated whereas in highly heterogeneous species, sequence divergence was observed and more than one PCR-DGGE profile was obtained. Application of the PCR-DGGE method to DNA extracted from faeces of zoo animals revealed the presence of Helicobacter DNA in 13 of 16 samples; a correlation was seen between the mobility of PCR products in DGGE analysis and DNA sequencing. In combination, this indicated that zoo animals are colonized by a wide range of different Helicobacter species; seven animals appeared to be colonized by multiple Helicobacter species. By this approach, presumptive identifications were made of Helicobacter bilis and Helicobacter hepaticus in a Nile crocodile, Helicobacter cinaedi in a baboon and a red panda, and Helicobacter felis in a wolf and a Taiwan beauty snake. All of these PCR products (400 bp) showed 100 % sequence similarity to 16S rDNA sequences of the mentioned species. These results demonstrate the potential of PCR-DGGE-based analysis for identification of Helicobacter species in complex ecosystems, such as the gastrointestinal tract, and could contribute to a better understanding of the ecology of helicobacters and other pathogens with a complex aetiology.
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| 2. |
- Coenye, Tom, et al.
(författare)
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Stenotrophomonas africana Drancourt et al. 1997 is a later synonym of Stenotrophomonas maltophilia (Hugh 1981) Palleroni and Bradbury 1993
- 2004
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Ingår i: INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY. - : Microbiology Society. - 1466-5026 .- 1466-5034. ; 54, s. 1235-1237
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Tidskriftsartikel (refereegranskat)abstract
- Type and reference strains of Stenotrophomonas maltophilia and Stenotrophomonas africana were compared with each other and with the type strains of other Stenotrophomonas species, using SDS-PAGE of whole-cell proteins, DNA–DNA hybridization and extensive biochemical characterization. S. maltophilia LMG 958T and S. africana LMG 22072T had very similar whole-cell-protein patterns and were also biochemically very similar. A DNA–DNA binding level of 70 % between both type strains confirmed that S. africana and S. maltophilia represent the same taxon. It is concluded that S. africana is a later synonym of S. maltophilia.
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| 3. |
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| 4. |
- Goris, Johan, et al.
(författare)
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Diversity of Transconjugants that Acquired Plasmid pJP4 or pEMT1 after Inoculation of a Donor Strain in the A- and B-horizon of an Agricultural Soil and Description of Burkholderia hospita sp. nov. and Burkholderia terricola sp. nov.
- 2002
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Ingår i: Systematic and Applied Microbiology. ; 25:3, s. 340-352
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Tidskriftsartikel (refereegranskat)abstract
- We examined the diversity of transconjugants that acquired the catabolic plasmids pJP4 or pEMT1, which encode degradation of 2,4-dichlorophenoxyacetic acid (2,4-D), in microcosms with agricultural soil inoculated with a donor strain (Dejonghe, W., Goris, J., El Fantroussi, S., Höfte, M., De Vos, P., Verstraete, W., and Top, E. M. Appl. Environ. Microbiol. 2000, p. 3297–3304). Using repetitive element PCR fingerprinting, eight different rep-clusters and six separate isolates could be discriminated among 95 transconjugants tested. Representative isolates were identified using 16S rDNA sequencing, cellular fatty acid analysis, whole-cell protein analysis and/or DNA-DNA hybridisations. Plasmids pJP4 and pEMT1 appeared to have a similar transfer and expression range, and were preferably acquired and expressed in soil by indigenous representatives of Ralstonia and Burkholderia. Two rep-clusters were shown to represent novel Burkholderia species, for which the names Burkholderia hospita sp. nov. and Burkholderia terricola sp. nov. are proposed. When easily degradable carbon sources were added together with the plasmid-bearing donor strain, also a significant proportion of Stenotrophomonas maltophilia isolates were found. The transconjugant collections isolated from A- (0–30 cm depth) and B-horizon (30–60 cm depth) soil were similar, except for B. terricola transconjugants, which were only isolated from the B-horizon.
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