Molecular analysis of a sulphate-reducing consortium used to treat metal-containing effluents.
A sulphate-reducing consortium used in a bioprocess to remove toxic metals from solution as insoluble sulphides, was characterised using molecular (PCR-based) and traditional culturing techniques. After prolonged cultivation under anoxic biofilm-forming conditions, the mixed culture contained a low diversity of sulphate-reducing bacteria, dominated by one strain closely related to Desulfomicrobium norvegicum, identified by three independent PCR-based analyses. The genetic targets used were the 16S rRNA gene, the 16S-23S rRNA gene intergenic spacer region and the disulfite reductase (dsr) gene, which is conserved amongst all known sulphate-reducing bacteria. This organism was also isolated by conventional anaerobic techniques, confirming its presence in the mixed culture. A surprising diversity of other non-sulphate-reducing facultative and obligate anaerobes were detected, supporting a model of the symbiotic/commensal nature of carbon and energy fluxes in such a mixed culture while suggesting the physiological capacity for a wide range of biotransformations by this stable microbial consortium.
Boothman
C
C
School of Earth, Atmospheric and Environmental Sciences and Williamson Research Centre for Molecular Environmental Science, University of Manchester, Manchester , UK.
Hockin
S
S
Holmes
D E
DE
Gadd
G M
GM
Lloyd
J R
JR
D001419:Bacteria / Q000235:genetics* / Q000378:metabolism; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology; D020564:Deltaproteobacteria / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D008670:Metals / Q000378:metabolism*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013431:Sulfates / Q000378:metabolism*; D013559:Symbiosis; D014871:Water Microbiology; D014874:Water Pollutants, Chemical / Q000378:metabolism*
D008670:Metals; D012336:RNA, Ribosomal, 16S; D013431:Sulfates; D014874:Water Pollutants, Chemical