TY - JOUR
T1 - In situ enrichment of a diverse community of bacteria from a 4–5 km deep fault zone in south africa
AU - Trimarco, Ellen
AU - Balkwill, David
AU - Davidson, Mark
AU - Onstott, Tullis C.
N1 - Funding Information:
This research was supported by grants from the National Science Foundation LExEn program (EAR-9978267) to Princeton University (T.C. Onstott). We gratefully acknowledge the support of Gold Fields Ltd. Thanks to D. Nell and J. Aucamp of Driefontein Gold Mine, as well as all researchers on the Witwatersrand Deep Microbiology Project. Thanks also to N. North, D. Moser, and T. Kieft for their support and inspiration.
PY - 2006
Y1 - 2006
N2 - The extreme environment of South Africa’s ultra-deep gold mines offers an opportunity to discover novel microorganisms (e.g., Alkaliphilus transvaalensis), including extremophiles that may provide insight into the origins of life on earth and offer industrial applications because of their thermophilic enzymatic properties. This study employed culture-independent methods to examine the bacterial diversity in water (T=55◦C, pH=9, Cl−=1000 ppm and age = 4–53 Ma) emanating from an exploration borehole in a South African Au mine that intersected a quartzite-hosted fault at 3.3 km below land surface. The more adhesive strains of sulfate reducing bacteria were effectively selected and enriched from the planktonic community by forcing water from a flowing borehole through a sand/agar cartridge that was installed within the borehole. The cartridge’s agar contained sulfate and lactate that diffused from the agar into the cartridge. DNA was extracted from the sand, after which a bacterial 16S rDNA gene clone library was generated. Analysis of clone sequences indicated that the groundwater bacterial community was quite diverse, including members of the α-, β-, and γ-Proteobacteria (20%), Actinobacteria (6%), Firmicutes (57%), Chloroflexi (3%), and Deinococcus- Thermus (14%) phyla. One of the most frequently detected clone types was associated with Desulfotomaculum (a known SRB). Another predominant clone type was closely related to Meiothermus cerbereus. A proportion of Proteobacteria clones were closely related to Ralstonia, Alishewanella, Hydrogenophaga, or Methylobacterium species. Some of the Firmicutes clones were closely related to Alkaliphilus transvaalensis, which was isolated froma nearby South African Au mine, or to Clostridium thermocellum. Of the total 21 OTUs identified from the cartridge sand, 6 most likely representnovel species of Firmicutes given their dissimilarity to other 16S rDNA sequences in the GenBank database.
AB - The extreme environment of South Africa’s ultra-deep gold mines offers an opportunity to discover novel microorganisms (e.g., Alkaliphilus transvaalensis), including extremophiles that may provide insight into the origins of life on earth and offer industrial applications because of their thermophilic enzymatic properties. This study employed culture-independent methods to examine the bacterial diversity in water (T=55◦C, pH=9, Cl−=1000 ppm and age = 4–53 Ma) emanating from an exploration borehole in a South African Au mine that intersected a quartzite-hosted fault at 3.3 km below land surface. The more adhesive strains of sulfate reducing bacteria were effectively selected and enriched from the planktonic community by forcing water from a flowing borehole through a sand/agar cartridge that was installed within the borehole. The cartridge’s agar contained sulfate and lactate that diffused from the agar into the cartridge. DNA was extracted from the sand, after which a bacterial 16S rDNA gene clone library was generated. Analysis of clone sequences indicated that the groundwater bacterial community was quite diverse, including members of the α-, β-, and γ-Proteobacteria (20%), Actinobacteria (6%), Firmicutes (57%), Chloroflexi (3%), and Deinococcus- Thermus (14%) phyla. One of the most frequently detected clone types was associated with Desulfotomaculum (a known SRB). Another predominant clone type was closely related to Meiothermus cerbereus. A proportion of Proteobacteria clones were closely related to Ralstonia, Alishewanella, Hydrogenophaga, or Methylobacterium species. Some of the Firmicutes clones were closely related to Alkaliphilus transvaalensis, which was isolated froma nearby South African Au mine, or to Clostridium thermocellum. Of the total 21 OTUs identified from the cartridge sand, 6 most likely representnovel species of Firmicutes given their dissimilarity to other 16S rDNA sequences in the GenBank database.
KW - 16S rDNA
KW - Groundwater
KW - Sulfate reduction
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U2 - 10.1080/01490450600875803
DO - 10.1080/01490450600875803
M3 - Article
AN - SCOPUS:85023887078
SN - 0149-0451
VL - 23
SP - 463
EP - 473
JO - Geomicrobiology Journal
JF - Geomicrobiology Journal
IS - 6
ER -