TY - JOUR
T1 - Hypoxic methane oxidation coupled to denitrification in a membrane biofilm
AU - Alrashed, Wael
AU - Lee, Jangho
AU - Park, Joonhong
AU - Rittmann, Bruce
AU - Tang, Youneng
AU - Neufeld, Josh D.
AU - Lee, Hyung Sool
N1 - Funding Information:
This work was financially supported by Natural Sciences and Engineering Research Council of Canada ( STPGP 478972 ) and the National Research Foundation of Korea (NRF) grant ( NRF-2016K1A3A1A12953714 ).
PY - 2018/9/15
Y1 - 2018/9/15
N2 - Methane oxidation coupled to denitrification (MOD) was tested in a membrane biofilm reactor (MBfR) using methane gas as the sole electron donor. Nitrate reduction to nitrite was rate limiting, and CH4 was present in the effluent. Slow kinetics of methane oxidation by bacteria were the factors that led to slow kinetics and incomplete removals. Methylocystaceae contained the largest fraction (21%) of bacterial SSU rRNA genes, and Archaea were nearly absent. The functional metagenome included all the genes essential for aerobic methane oxidation (pmo, mdh, mtdB, folD, and fdh) and nitrate reduction to dinitrogen (nap/nar, nir, nor and nos), but not for reverse methanogenesis (mcr). The functional metagenome supports that Methylocystaceae conducted MOD in syntrophy with heterotrophic denitrifiers (e.g., Comamonadaceae and Brucellaceae), suggesting aerobic MOD. DO measurements, serum-bottle tests, and calculation of O2 permeation bolster hypoxically aerobic MOD would mainly account for denitrification in the MBfR.
AB - Methane oxidation coupled to denitrification (MOD) was tested in a membrane biofilm reactor (MBfR) using methane gas as the sole electron donor. Nitrate reduction to nitrite was rate limiting, and CH4 was present in the effluent. Slow kinetics of methane oxidation by bacteria were the factors that led to slow kinetics and incomplete removals. Methylocystaceae contained the largest fraction (21%) of bacterial SSU rRNA genes, and Archaea were nearly absent. The functional metagenome included all the genes essential for aerobic methane oxidation (pmo, mdh, mtdB, folD, and fdh) and nitrate reduction to dinitrogen (nap/nar, nir, nor and nos), but not for reverse methanogenesis (mcr). The functional metagenome supports that Methylocystaceae conducted MOD in syntrophy with heterotrophic denitrifiers (e.g., Comamonadaceae and Brucellaceae), suggesting aerobic MOD. DO measurements, serum-bottle tests, and calculation of O2 permeation bolster hypoxically aerobic MOD would mainly account for denitrification in the MBfR.
KW - Denitrification
KW - Dissolved methane
KW - Metagenome
KW - Methane oxidation
KW - Methanotrophs
KW - Methylocystaceae
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U2 - 10.1016/j.cej.2018.04.202
DO - 10.1016/j.cej.2018.04.202
M3 - Article
AN - SCOPUS:85047086628
VL - 348
SP - 745
EP - 753
JO - Chemical Engineering Journal
JF - Chemical Engineering Journal
SN - 1385-8947
ER -