Dataset Information

Microbial hitchhikers on intercontinental dust: catching a lift in Chad.

ABSTRACT: Ancient mariners knew that dust whipped up from deserts by strong winds travelled long distances, including over oceans. Satellite remote sensing revealed major dust sources across the Sahara. Indeed, the Bodélé Depression in the Republic of Chad has been called the dustiest place on earth. We analysed desert sand from various locations in Chad and dust that had blown to the Cape Verde Islands. High throughput sequencing techniques combined with classical microbiological methods showed that the samples contained a large variety of microbes well adapted to the harsh desert conditions. The most abundant bacterial groupings in four different phyla included: (a) Firmicutes-Bacillaceae, (b) Actinobacteria-Geodermatophilaceae, Nocardiodaceae and Solirubrobacteraceae, (c) Proteobacteria-Oxalobacteraceae, Rhizobiales and Sphingomonadaceae, and (d) Bacteroidetes-Cytophagaceae. Ascomycota was the overwhelmingly dominant fungal group followed by Basidiomycota and traces of Chytridiomycota, Microsporidia and Glomeromycota. Two freshwater algae (Trebouxiophyceae) were isolated. Most predominant taxa are widely distributed land inhabitants that are common in soil and on the surfaces of plants. Examples include Bradyrhizobium spp. that nodulate and fix nitrogen in Acacia species, the predominant trees of the Sahara as well as Herbaspirillum (Oxalobacteraceae), a group of chemoorganotrophic free-living soil inhabitants that fix nitrogen in association with Gramineae roots. Few pathogenic strains were found, suggesting that African dust is not a large threat to public health.

SUBMITTER: Favet J

PROVIDER: S-EPMC3603401 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Microbial hitchhikers on intercontinental dust: catching a lift in Chad.

Favet Jocelyne J Lapanje Ales A Giongo Adriana A Kennedy Suzanne S Aung Yin-Yin YY Cattaneo Arlette A Davis-Richardson Austin G AG Brown Christopher T CT Kort Renate R Brumsack Hans-Jürgen HJ Schnetger Bernhard B Chappell Adrian A Kroijenga Jaap J Beck Andreas A Schwibbert Karin K Mohamed Ahmed H AH Kirchner Timothy T de Quadros Patricia Dorr PD Triplett Eric W EW Broughton William J WJ Gorbushina Anna A AA

The ISME journal 20121220 4

Ancient mariners knew that dust whipped up from deserts by strong winds travelled long distances, including over oceans. Satellite remote sensing revealed major dust sources across the Sahara. Indeed, the Bodélé Depression in the Republic of Chad has been called the dustiest place on earth. We analysed desert sand from various locations in Chad and dust that had blown to the Cape Verde Islands. High throughput sequencing techniques combined with classical microbiological methods showed that the ...[more]

PMID: 23254516

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Dataset Information

Microbial hitchhikers on intercontinental dust: catching a lift in Chad.

Publications

Microbial hitchhikers on intercontinental dust: catching a lift in Chad.

Similar Datasets

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