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Title: Changes in bacterial community structure correlate with initialoperating conditions of a field-scale denitrifying fluidized bedreactor

Abstract

High levels of nitrate are present in groundwater migratingfrom the former waste disposal ponds at the Y-12 National SecurityComplex in Oak Ridge, TN. A field-scale denitrifying fluidized bedreactor (FBR) was designed, constructed, and operated with ethanol as anelectron donor for the removal of nitrate. After inoculation, biofilmsdeveloped on the granular activated carbon particles. Changes in thebacterial community of the FBR were evaluated with clone libraries (n=500partial sequences) of the small-subunit rRNA gene for samples taken overa 4-month start-up period. Early phases of start-up operationwerecharacterized by a period of selection, followed by low diversity andpredominance by Azoarcus-like sequences. Possible explanations were highpH and nutrient limitations. After amelioration of these conditions,diversification increased rapidly, with the appearance of Dechloromonas,Pseudomonas, and Hydrogenophaga sequences. Changes in NO3, SO4, and pHalso likely contributed to shifts in community composition. The detectionof sulfate-reducing-bacteria-like sequences closely related toDesulfovibrio and Desulfuromonas in the FBR have important implicationsfor downstream applications at the field site.

Authors:
; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
COLLABORATION - MiamiU.
OSTI Identifier:
903366
Report Number(s):
LBNL-60455
Journal ID: ISSN 0175-7598; AMBIDG; R&D Project: VGTLTH; BnR: KP1102010; TRN: US200720%%298
DOE Contract Number:
DE-AC02-05CH11231
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Microbiology and Biotechnology; Journal Volume: 71; Journal Issue: 5; Related Information: Journal Publication Date: August, 2006
Country of Publication:
United States
Language:
English
Subject:
54; 59; ACTIVATED CARBON; BINDING ENERGY; DESULFOVIBRIO; DIVERSIFICATION; ELECTRONS; ETHANOL; FLUIDIZED BED REACTORS; GENES; INOCULATION; NATIONAL SECURITY; NITRATES; NUTRIENTS; PONDS; PSEUDOMONAS; START-UP; VALENCE; WASTE DISPOSAL; Bioremediation Stress Response sulfate reducers fieldstudies

Citation Formats

Hwang, C., Wu, W.-M., Gentry, T.J., Carley, J., Carroll, S.L., Schadt, C., Watson, D., Jardine, P.M., Zhou, J., Hickey, R.F., Criddle,C.S., and Fields, M.W. Changes in bacterial community structure correlate with initialoperating conditions of a field-scale denitrifying fluidized bedreactor. United States: N. p., 2007. Web.
Hwang, C., Wu, W.-M., Gentry, T.J., Carley, J., Carroll, S.L., Schadt, C., Watson, D., Jardine, P.M., Zhou, J., Hickey, R.F., Criddle,C.S., & Fields, M.W. Changes in bacterial community structure correlate with initialoperating conditions of a field-scale denitrifying fluidized bedreactor. United States.
Hwang, C., Wu, W.-M., Gentry, T.J., Carley, J., Carroll, S.L., Schadt, C., Watson, D., Jardine, P.M., Zhou, J., Hickey, R.F., Criddle,C.S., and Fields, M.W. Mon . "Changes in bacterial community structure correlate with initialoperating conditions of a field-scale denitrifying fluidized bedreactor". United States. doi:.
@article{osti_903366,
title = {Changes in bacterial community structure correlate with initialoperating conditions of a field-scale denitrifying fluidized bedreactor},
author = {Hwang, C. and Wu, W.-M. and Gentry, T.J. and Carley, J. and Carroll, S.L. and Schadt, C. and Watson, D. and Jardine, P.M. and Zhou, J. and Hickey, R.F. and Criddle,C.S. and Fields, M.W.},
abstractNote = {High levels of nitrate are present in groundwater migratingfrom the former waste disposal ponds at the Y-12 National SecurityComplex in Oak Ridge, TN. A field-scale denitrifying fluidized bedreactor (FBR) was designed, constructed, and operated with ethanol as anelectron donor for the removal of nitrate. After inoculation, biofilmsdeveloped on the granular activated carbon particles. Changes in thebacterial community of the FBR were evaluated with clone libraries (n=500partial sequences) of the small-subunit rRNA gene for samples taken overa 4-month start-up period. Early phases of start-up operationwerecharacterized by a period of selection, followed by low diversity andpredominance by Azoarcus-like sequences. Possible explanations were highpH and nutrient limitations. After amelioration of these conditions,diversification increased rapidly, with the appearance of Dechloromonas,Pseudomonas, and Hydrogenophaga sequences. Changes in NO3, SO4, and pHalso likely contributed to shifts in community composition. The detectionof sulfate-reducing-bacteria-like sequences closely related toDesulfovibrio and Desulfuromonas in the FBR have important implicationsfor downstream applications at the field site.},
doi = {},
journal = {Applied Microbiology and Biotechnology},
number = 5,
volume = 71,
place = {United States},
year = {Mon Apr 02 00:00:00 EDT 2007},
month = {Mon Apr 02 00:00:00 EDT 2007}
}
  • High levels of nitrate are present in groundwater migrating from the former waste disposal ponds at the Y-12 National Security Complex in Oak Ridge, TN. A field-scale denitrifying fluidized bed reactor (FBR) was designed, constructed, and operated with ethanol as an electron donor for the removal of nitrate. After inoculation, biofilms developed on the granular activated carbon particles. Changes in the bacterial community of the FBR were evaluated with clone libraries (n=500 partial sequences) of the small-subunit rRNA gene for samples taken over a 4-month start-up period. Early phases of start-up operation were characterized by a period of selection, followedmore » by low diversity and predominance by Azoarcus-like sequences. Possible explanations were high pH and nutrient limitations. After amelioration of these conditions, diversification increased rapidly, with the appearance of Dechloromonas, Pseudomonas, and Hydrogenophaga sequences. Changes in NO{sub 3}, SO{sub 4}, and pH also likely contributed to shifts in community composition. The detection of sulfate-reducing-bacteria-like sequences closely related to Desulfovibrio and Desulfuromonas in the FBR have important implications for downstream applications at the field site.« less
  • High levels of nitrate are present in groundwater migrating from the former waste disposal ponds at the Y-12 National Security Complex in Oak Ridge, TN. A field-scale denitrifying fluidized bed reactor (FBR) was designed, constructed, and operated with ethanol as an electron donor for the removal of nitrate. After inoculation, biofilms developed on the granular activated carbon particles. Changes in the bacterial community of the FBR were evaluated with clone libraries (n=500 partial sequences) of the small-subunit rRNA gene for samples taken over a 4-month start-up period. Early phases of start-up operation were characterized by a period of selection, followedmore » by low diversity and predominance by Azoarcus-like sequences. Possible explanations were high pH and nutrient limitations. After amelioration of these conditions, diversification increased rapidly, with the appearance of Dechloromonas, Pseudomonas, and Hydrogenophaga sequences. Changes in NO{sub 3}, SO{sub 4}, and pH also likely contributed to shifts in community composition. The detection of sulfate-reducing-bacteria-like sequences closely related to Desulfovibrio and Desulfuromonas in the FBR have important implications for downstream applications at the field site.« less
  • The species (cytospecies) structure and seasonal dynamics of a thermophilic bluegreen algal/bacterial community from Mimbres, New Mexico are described. Using stereological techniques, several common quantitative ecological parameters (biomass, density, distribution measurements, Species Diversity Indices, importance values) were described for the community growing ca. 1 m beneath the water surface on the inner walls of a concrete cistern. Temperature and pH were relatively constant while water flow rates, duration and intensity of light showed seasonal variation. The total volume of the mat occupied by living organsisms did not exceed 2% during the entire year. The remaining volume was occupied by gasmore » and water bubble chambers, gelatinous matrix, empty tubes, mineral deposits, and water. The total biomass remained constant except during a period of severe, seasonal light reduction (November). Species Diversity Indices, density and importance values for the bluegreen algal and bacterial populations showed seasonal changes. The three dominant bluegreen algal cytospecies which represented the greatest amount of biomass alternated in their abundance on a seasonal basis while the three dominant bacterial cytospecies remained the same throughout the period of study. Although considerable season change occurred in the species structure of this community, the total living volume remainedrelatively constant with the major changes in the bluegreen algal populations. Many of the seasonal changes observed appear to correlate with seasonal changes in light intensity and duration.« less
  • Heterotrophic bacterial communities in water and sediment samples from 3 sites in a reservoir receiving acid mine drainage water were studied for stress-related changes due to the pollution. Acridine range direct counts and heterotrophic plate counts were made. Community similarity and numbers of acid and metal tolerant isolates were determined. Bacterial diversity was lower in water polluted by acid mine drainage and there were reduced numbers of heterotrophic bacteria.
  • Spatial heterogeneity in physical, chemical, and biological properties of soils allows for the proliferation of diverse microbial communities. Factors influencing the structuring of microbial communities, including availability of nutrients and water, pH, and soil texture, can vary considerably with soil depth and within soil aggregates. Here we investigated changes in the microbial and functional communities within soil aggregates obtained along a soil profile spanning the surface, vadose zone, and saturated soil environments. The composition and diversity of microbial communities and specific functional groups involved in key pathways in the geochemical cycling of nitrogen, Fe, and sulfur were characterized using amore » coupled approach involving cultivation-independent analysis of both 16S rRNA (bacterial and archaeal) and functional genes (amoA and dsrAB) as well as cultivation-based analysis of Fe(III)-reducing organisms. Here we found that the microbial communities and putative ammonia-oxidizing and Fe(III)-reducing communities varied greatly along the soil profile, likely reflecting differences in carbon availability, water content, and pH. In particular, the Crenarchaeota 16S rRNA sequences are largely unique to each horizon, sharing a distribution and diversity similar to those of the putative (amoA-based) ammonia-oxidizing archaeal community. Anaerobic microenvironments within soil aggregates also appear to allow for both anaerobic- and aerobic-based metabolisms, further highlighting the complexity and spatial heterogeneity impacting microbial community structure and metabolic potential within soils.« less