Response of Ammonia-oxidizing Bacterial and Archaeal Populations to Organic Nitrogen Amendments in Low-Nutrient Groundwater

Journal Article · Mon Feb 01 04:00:00 EST 2010 · Applied and Environmental Microbiology

DOI:https://doi.org/10.1128/AEM.02436-09· OSTI ID:975155

Reed, David W; Fujita, Yoshiko; Smith, Jason M; Francis, Christopher A

To better understand the fate of ammonia introduced into low-nutrient groundwater as a result of the application of a novel remediation approach for trace metal contaminants, the diversity and abundance of ammonia-oxidizing bacteria and archaea (AOB and AOA, respectively) were examined in samples collected during a field trial of the approach. The ammonia is derived from microbial urea hydrolysis, which has the potential to induce the formation of calcite and remove contaminants by coprecipitation in the calcite. The in situ oxidation of the ammonia by AOB and AOA could, however, potentially destabilize the calcite and lead to elevated nitrate levels in the groundwater. To evaluate the potential for stimulating ammonia oxidation by addition of urea, samples were collected from the Eastern Snake River Plain Aquifer in Idaho before, during, and after the addition of molasses and urea, and subjected to PCR analysis of ammonia monooxygenase subunit A (amoA) genes. AOB and AOA were present in all of the samples tested, with the AOA amoA genes more numerous in all of the samples except those collected following urea addition, when AOB genes were slightly more abundant. Following urea addition, nitrate levels rose and ammonia-oxidizing microorganisms (AOB + AOA) increased relative to the total microbial population, evidence that nitrification was stimulated by urea hydrolysis. Bacterial amoA diversity was limited to two sequence types, whereas the archaeal amoA analyses revealed 20 unique operational taxonomic units (OTUs), including several that were significantly different from any reported previously from other environments. In view of the results from this study, the potential for stimulation of ammonia-oxidizing communities should be considered in field-scale engineering activities involving microbial urea hydrolysis in groundwater.

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: DOE - SC
• DOE Contract Number: AC07-05ID14517
• OSTI ID: 975155
• Report Number(s): INL/JOU-09-15772
• Journal Information: Applied and Environmental Microbiology, Journal Name: Applied and Environmental Microbiology Journal Issue: 8 Vol. 76; ISSN AEMIDF; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ABUNDANCE
AMMONIA
AQUIFERS
BACTERIA
CALCITE
COMMUNITIES
COPRECIPITATION
GENES
GROUND WATER
HYDROLYSIS
MICROORGANISMS
MOLASSES
NITRATES
NITRIFICATION
NITROGEN
OXIDATION
SNAKE RIVER PLAIN
STIMULATION
UREA
ammonia monooxygenase
ammonia oxidation
calcite precipitation
qPCR
trace metal or raionuclide remediation