Vacuolated Beggiatoa-like filaments from different hypersaline environments form a novel genus
Article first published online: 8 JUN 2011
© 2011 Society for Applied Microbiology and Blackwell Publishing Ltd
Thematic Issue: Human Microbiome
Volume 13, Issue 12, pages 3194–3205, December 2011
How to Cite
Hinck, S., Mußmann, M., Salman, V., Neu, T. R., Lenk, S., de Beer, D. and Jonkers, H. M. (2011), Vacuolated Beggiatoa-like filaments from different hypersaline environments form a novel genus. Environmental Microbiology, 13: 3194–3205. doi: 10.1111/j.1462-2920.2011.02513.x
- Issue published online: 30 NOV 2011
- Article first published online: 8 JUN 2011
- Received 12 June, 2009; accepted 14 April, 2011.
Vol. 14, Issue 12, 3287, Article first published online: 4 DEC 2012
In this study, members of a specific group of thin (6–14 µm filament diameter), vacuolated Beggiatoa-like filaments from six different hypersaline microbial mats were morphologically and phylogenetically characterized. Therefore, enrichment cultures were established, filaments were stained with fluorochromes to show intracellular structures and 16S rRNA genes were sequenced. Morphological characteristics of Beggiatoa-like filaments, in particular the presence of intracellular vacuoles, and the distribution of nucleic acids were visualized. In the intracellular vacuole nitrate reached concentrations of up to 650 mM. Fifteen of the retrieved 16S rRNA gene sequences formed a monophyletic cluster and were phylogenetically closely related (≥ 94.4% sequence identity). Sequences of known filamentous sulfide-oxidizing genera Beggiatoa and Thioploca that comprise non-vacuolated and vacuolated filaments from diverse habitats clearly delineated from this cluster. The novel monophyletic cluster was furthermore divided into two sub-clusters: one contained sequences originating from Guerrero Negro (Mexico) microbial mats and the other comprised sequences from five distinct Spanish hypersaline microbial mats from Ibiza, Formentera and Lake Chiprana. Our data suggest that Beggiatoa-like filaments from hypersaline environments displaying a thin filament diameter contain nitrate-storing vacuoles and are phylogenetically separate from known Beggiatoa. Therefore, we propose a novel genus for these organisms, which we suggest to name ‘Candidatus Allobeggiatoa’.