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Comparisons of the composition and biogeographic distribution of the bacterial communities occupying South African thermal springs with those inhabiting deep subsurface fracture water.

Magnabosco C, Tekere M, Lau MC, Linage B, Kuloyo O, Erasmus M, Cason E, van Heerden E, Borgonie G, Kieft TL, Olivier J, Onstott TC - Front Microbiol (2014)

Bottom Line: Proteobacteria were identified as the dominant phylum within both subsurface and thermal spring environments, but only one genera, Rheinheimera, was identified among all samples.Using Morisita similarity indices as a metric for pairwise comparisons between sites, we found that the communities of thermal springs are highly distinct from subsurface datasets.Although the Limpopo thermal springs do not appear to provide a new window for viewing subsurface bacterial communities, we report that the taxonomic compositions of the subsurface sites studied are more similar than previous results would indicate and provide evidence that the microbial communities sampled at depth are more correlated to subsurface conditions than geographical distance.

View Article: PubMed Central - PubMed

Affiliation: Department of Geosciences, Princeton University Princeton, NJ, USA.

ABSTRACT
South Africa has numerous thermal springs that represent topographically driven meteoric water migrating along major fracture zones. The temperature (40-70°C) and pH (8-9) of the thermal springs in the Limpopo Province are very similar to those of the low salinity fracture water encountered in the South African mines at depths ranging from 1.0 to 3.1 km. The major cation and anion composition of these thermal springs are very similar to that of the deep fracture water with the exception of the dissolved inorganic carbon and dissolved O2, both of which are typically higher in the springs than in the deep fracture water. The in situ biological relatedness of such thermal springs and the subsurface fracture fluids that feed them has not previously been evaluated. In this study, we evaluated the microbial diversity of six thermal spring and six subsurface sites in South Africa using high-throughput sequencing of 16S rRNA gene hypervariable regions. Proteobacteria were identified as the dominant phylum within both subsurface and thermal spring environments, but only one genera, Rheinheimera, was identified among all samples. Using Morisita similarity indices as a metric for pairwise comparisons between sites, we found that the communities of thermal springs are highly distinct from subsurface datasets. Although the Limpopo thermal springs do not appear to provide a new window for viewing subsurface bacterial communities, we report that the taxonomic compositions of the subsurface sites studied are more similar than previous results would indicate and provide evidence that the microbial communities sampled at depth are more correlated to subsurface conditions than geographical distance.

No MeSH data available.


Related in: MedlinePlus

Subsurface taxonomic distribution. A bar plot of the relative abundance (x-axis) of various phyla (color) per subsurface site (y-axis). Due to its high relative abundance, the phylum proteobacteria was split into its corresponding classes. Members of the “Other” bin include: BRC1, Caldiserica, Chlamydiae, Chloroplast, Crenarchaeota, Dictyoglomi, Elusimicrobia, Euryarchaeota, Fibrobacteres, Gemmatimonadetes, Lentisphaerae, Mitochondria, OP1, OP2, OP8, OP10, OP11, Spirochaetes, Synergistetes, TA06, Tenericutes, TG-1, Thermotogae, TM6, TM7, WS1, WS3, WS6, and Zetaproteobacteria.
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Figure 3: Subsurface taxonomic distribution. A bar plot of the relative abundance (x-axis) of various phyla (color) per subsurface site (y-axis). Due to its high relative abundance, the phylum proteobacteria was split into its corresponding classes. Members of the “Other” bin include: BRC1, Caldiserica, Chlamydiae, Chloroplast, Crenarchaeota, Dictyoglomi, Elusimicrobia, Euryarchaeota, Fibrobacteres, Gemmatimonadetes, Lentisphaerae, Mitochondria, OP1, OP2, OP8, OP10, OP11, Spirochaetes, Synergistetes, TA06, Tenericutes, TG-1, Thermotogae, TM6, TM7, WS1, WS3, WS6, and Zetaproteobacteria.

Mentions: Although the subsurface rarefaction curves (Supplement Figure 5) did not attain a plateau, the reduced slope of each curve toward the terminus suggested that the sequences for each of these samples are representative of their bacterial community. Across all sites, Proteobacteria were the most abundant phylum, with relative abundances ranging from 49% (Dr5IPC) to 59% (Be326_2012) (Figure 3). Weighted, pairwise Unifrac significance tests indicated that all sites were significantly different (p < 0.001); however, unweighted, pairwise UniFrac significance tests revealed that only 7 of the 21 pairs of sites were found to be significantly different (p < 0.05) from one another (Supplement Figure 6). All subsurface sites displayed a Pielou's evenness between 0.77 (TT109) and 0.80 (MM51940) (Table 3). Previous studies of South African fracture fluids (Takai et al., 2001; Moser et al., 2003, 2005; Kieft et al., 2005; Gihring et al., 2006; Lin et al., 2006a,b; Borgonie et al., 2011) identified a total of 243 unique genera in the South African subsurface (Chehoud, 2011). Of these 243 genera, 139 were observed in our V6 datasets.


Comparisons of the composition and biogeographic distribution of the bacterial communities occupying South African thermal springs with those inhabiting deep subsurface fracture water.

Magnabosco C, Tekere M, Lau MC, Linage B, Kuloyo O, Erasmus M, Cason E, van Heerden E, Borgonie G, Kieft TL, Olivier J, Onstott TC - Front Microbiol (2014)

Subsurface taxonomic distribution. A bar plot of the relative abundance (x-axis) of various phyla (color) per subsurface site (y-axis). Due to its high relative abundance, the phylum proteobacteria was split into its corresponding classes. Members of the “Other” bin include: BRC1, Caldiserica, Chlamydiae, Chloroplast, Crenarchaeota, Dictyoglomi, Elusimicrobia, Euryarchaeota, Fibrobacteres, Gemmatimonadetes, Lentisphaerae, Mitochondria, OP1, OP2, OP8, OP10, OP11, Spirochaetes, Synergistetes, TA06, Tenericutes, TG-1, Thermotogae, TM6, TM7, WS1, WS3, WS6, and Zetaproteobacteria.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4269199&req=5

Figure 3: Subsurface taxonomic distribution. A bar plot of the relative abundance (x-axis) of various phyla (color) per subsurface site (y-axis). Due to its high relative abundance, the phylum proteobacteria was split into its corresponding classes. Members of the “Other” bin include: BRC1, Caldiserica, Chlamydiae, Chloroplast, Crenarchaeota, Dictyoglomi, Elusimicrobia, Euryarchaeota, Fibrobacteres, Gemmatimonadetes, Lentisphaerae, Mitochondria, OP1, OP2, OP8, OP10, OP11, Spirochaetes, Synergistetes, TA06, Tenericutes, TG-1, Thermotogae, TM6, TM7, WS1, WS3, WS6, and Zetaproteobacteria.
Mentions: Although the subsurface rarefaction curves (Supplement Figure 5) did not attain a plateau, the reduced slope of each curve toward the terminus suggested that the sequences for each of these samples are representative of their bacterial community. Across all sites, Proteobacteria were the most abundant phylum, with relative abundances ranging from 49% (Dr5IPC) to 59% (Be326_2012) (Figure 3). Weighted, pairwise Unifrac significance tests indicated that all sites were significantly different (p < 0.001); however, unweighted, pairwise UniFrac significance tests revealed that only 7 of the 21 pairs of sites were found to be significantly different (p < 0.05) from one another (Supplement Figure 6). All subsurface sites displayed a Pielou's evenness between 0.77 (TT109) and 0.80 (MM51940) (Table 3). Previous studies of South African fracture fluids (Takai et al., 2001; Moser et al., 2003, 2005; Kieft et al., 2005; Gihring et al., 2006; Lin et al., 2006a,b; Borgonie et al., 2011) identified a total of 243 unique genera in the South African subsurface (Chehoud, 2011). Of these 243 genera, 139 were observed in our V6 datasets.

Bottom Line: Proteobacteria were identified as the dominant phylum within both subsurface and thermal spring environments, but only one genera, Rheinheimera, was identified among all samples.Using Morisita similarity indices as a metric for pairwise comparisons between sites, we found that the communities of thermal springs are highly distinct from subsurface datasets.Although the Limpopo thermal springs do not appear to provide a new window for viewing subsurface bacterial communities, we report that the taxonomic compositions of the subsurface sites studied are more similar than previous results would indicate and provide evidence that the microbial communities sampled at depth are more correlated to subsurface conditions than geographical distance.

View Article: PubMed Central - PubMed

Affiliation: Department of Geosciences, Princeton University Princeton, NJ, USA.

ABSTRACT
South Africa has numerous thermal springs that represent topographically driven meteoric water migrating along major fracture zones. The temperature (40-70°C) and pH (8-9) of the thermal springs in the Limpopo Province are very similar to those of the low salinity fracture water encountered in the South African mines at depths ranging from 1.0 to 3.1 km. The major cation and anion composition of these thermal springs are very similar to that of the deep fracture water with the exception of the dissolved inorganic carbon and dissolved O2, both of which are typically higher in the springs than in the deep fracture water. The in situ biological relatedness of such thermal springs and the subsurface fracture fluids that feed them has not previously been evaluated. In this study, we evaluated the microbial diversity of six thermal spring and six subsurface sites in South Africa using high-throughput sequencing of 16S rRNA gene hypervariable regions. Proteobacteria were identified as the dominant phylum within both subsurface and thermal spring environments, but only one genera, Rheinheimera, was identified among all samples. Using Morisita similarity indices as a metric for pairwise comparisons between sites, we found that the communities of thermal springs are highly distinct from subsurface datasets. Although the Limpopo thermal springs do not appear to provide a new window for viewing subsurface bacterial communities, we report that the taxonomic compositions of the subsurface sites studied are more similar than previous results would indicate and provide evidence that the microbial communities sampled at depth are more correlated to subsurface conditions than geographical distance.

No MeSH data available.


Related in: MedlinePlus