A Novel Autotrophic Bacterium Isolated from an Engineered Wetland System Links Nitrate-Coupled Iron Oxidation to the Removal of As, Zn and S

• Published in: Water, air, and soil pollution Vol. 224; no. 4; pp. 1 - 15
• Main Authors: Mattes, Al, Gould, Douglas, Taupp, Marcus, Glasauer, Susan
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-04-2013; Springer; Springer Nature B.V
• Subjects: Analysis; Anoxic conditions; Applied sciences; Arsenic; Arsenic removal; Atmospheric Protection/Air Quality Control/Air Pollution; Bacteria; Bioremediation; Biosolids; Cell surface; Climate Change/Climate Change Impacts; Earth and Environmental Science; Environment; Environmental monitoring; Exact sciences and technology; Ferric oxide; Homology; Hydrogeology; Iron; Iron compounds; Iron oxides; Iron-oxidizing bacteria; Iron-reducing bacteria; Landfill; Landfills; Leukocytes (neutrophilic); Nitrate reduction; Nitrates; Oxidation; Oxidation-reduction reaction; Pollution; Refuse and refuse disposal; Sediments; Soil Science & Conservation; Statistical analysis; Studies; Sulfates; Surface flow; Waste disposal sites; Water pollution; Water Quality/Water Pollution; Wetlands; Zinc; British Columbia Canada; Canada; Canada, British Columbia; Sulfate reduction; Arsenic; Wetland; Zinc; Iron-oxidizing bacteria; Sulfur compounds; Nitrogen compounds; Autotrophy; Iron; Nitrates; Sulfates; Heavy metal; Chemical reduction; Trace element; Carcinogen; Pollution; Decontamination; Artificial medium; Constructed wetland; Bacteria; Poison; Oxidation
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-013-1490-8

A neutrophilic, autotrophic bacterium that couples iron oxidation to nitrate reduction (iron-oxidizing bacteria [IOB]) under anoxic conditions was isolated from a working bioremediation site in Trail, British Columbia. The site was designed and developed primarily to treat high concentrations of Zn and As that originate from capped industrial landfill sites. The system consisted of two upflow biochemical reactor cells (BCR) followed by three vegetated wetland polishing cells with sub-surface flow and a holding pond. During a 5-year period (2003–2007), the system treated more than 19,100 m
3
of contaminated water, removing and sequestering more than 10,700 kg of As, Zn and sulfate at average input water concentrations of: As, 58.6 mg l
−1
(±39.9 mg l
−1
); Zn, 51.9 mg l
−1
(±35.4 mg l
−1
) and SO
4
2−
, 781.5 mg l
−1
(±287.8 mg l
−1
). The bacterium was isolated in order to better understand the mechanisms underlying the consistent As removal that took place in the system. Analysis using Basic Local Alignment Search Tool (BLAST) database showed that the closest homologies are to
Candidatus accumulibacterphosphatis
(95 % homology),
Dechloromonas aromatica
(94 %), and
Sideroxydans lithotrophicus
ES-1 (92 %) Within the BCR cells, the IOB oxidized Fe
2+
generated by iron-reducing bacteria (IRB); the source of the iron was most likely biosolids and coatings of iron oxide on locally available sand used in the matrix. We have provisionally designated the novel bacterium as TR1.