Article

Porca E, Jurado V, Zgur-Bertok D, Saiz-Jimenez C, Pasic L.. Comparative analysis of yellow microbial communities growing on the walls of geographically distinct caves indicates a common core of microorganisms involved in their formation. FEMS Microbiol Ecol 81: 255-266

Instituto de Recursos Naturales y Agrobiologia, IRNAS-CSIC, Seville, Spain.
FEMS Microbiology Ecology (Impact Factor: 3.57). 04/2012; 81(1):255-66. DOI: 10.1111/j.1574-6941.2012.01383.x
Source: PubMed

ABSTRACT

Morphologically similar microbial communities that often form on the walls of geographically distinct limestone caves have not yet been comparatively studied. Here, we analysed phylotype distribution in yellow microbial community samples obtained from the walls of distinct caves located in Spain, Czech Republic and Slovenia. To infer the level of similarity in microbial community membership, we analysed inserts of 474 16S rRNA gene clones and compared those using statistical tools. The results show that the microbial communities under investigation are composed solely of Bacteria. The obtained phylotypes formed three distinct groups of operational taxonomic units (OTUs). About 60% of obtained sequences formed three core OTUs common to all three sampling sites. These were affiliated with actinobacterial Pseudonocardinae (30-50% of sequences in individual sampling site libraries), but also with gammaproteobacterial Chromatiales (6-25%) and Xanthomonadales (0.5-2.0%). Another 7% of sequences were common to two sampling sites and formed eight OTUs, while the remaining 35% were site specific and corresponded mostly to OTUs containing single sequences. The same pattern was observed when these data were compared with sequence data available from similar studies. This comparison showed that distinct limestone caves support microbial communities composed mostly of phylotypes common to all sampling sites.

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    • "In this cave the outbreak was produced by complex bacterial communities which form spots of yellow, white and gray color (Saiz-Jimenez et al., 2011). Each colored spot is composed of a high number of different bacteria from distinct phyla (Cuezva et al., 2012; Porca et al., 2012) and therefore it would be impossible to apply a similar protocol to quantify the dispersion of a single microorganism, that by the way would not be majority. "
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