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Title: Identification and environmental distribution of dcpA encoding the 1,2-dichloropropane-to-propene reductive dehalogenase in organohalide-respiring Chloroflexi

Abstract

Dehalococcoides mccartyi (Dhc) strains KS and RC grow with 1,2-dichloropropane (1,2-D) as an electron acceptor in enrichment cultures derived from hydrocarbon-contaminated and pristine river sediments, respectively. Transcription, expression, enzymatic and PCR analyses implicated the reductive dehalogenase gene dcpA in 1,2-D dichloroelimination to propene and inorganic chloride. Quantitative real-time PCR (qPCR) analyses demonstrated Dhc cell increase during growth with 1,2-D and suggested that both Dhc strains carried a single dcpA gene copy per genome. Dhc strain RC and strain KS produced 1.8 0.1 x 107 and 1.4 0.5 x 107 cells per mole of propene formed, respectively. The dcpA gene was identified in 1,2-D-to-propene-dechlorinating microcosms established with sediment samples collected from different geographical locations in Europe and North and South America. Clone library analysis revealed two distinct dcpA phylogenetic clusters, both of which the dcpA gene-targeted qPCR assay captured, suggesting the qPCR assay is useful for site assessment and bioremediation monitoring at 1,2-D-contaminated sites.

Authors:
 [1];  [2];  [2];  [2];  [3];  [2];  [2]
  1. University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL)
  2. ORNL
  3. {Bob} L [ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1118749
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied and Environmental Microbiology; Journal Volume: 80; Journal Issue: 3
Country of Publication:
United States
Language:
English

Citation Formats

Padilla-Crespo, Elizabeth, Yan, Jun, Swift, Cynthia M, Chourey, Karuna, Hettich, Robert, Ritalahti, Kirsti M, and Loeffler, Frank E. Identification and environmental distribution of dcpA encoding the 1,2-dichloropropane-to-propene reductive dehalogenase in organohalide-respiring Chloroflexi. United States: N. p., 2014. Web. doi:10.1128/AEM.02927-13.
Padilla-Crespo, Elizabeth, Yan, Jun, Swift, Cynthia M, Chourey, Karuna, Hettich, Robert, Ritalahti, Kirsti M, & Loeffler, Frank E. Identification and environmental distribution of dcpA encoding the 1,2-dichloropropane-to-propene reductive dehalogenase in organohalide-respiring Chloroflexi. United States. doi:10.1128/AEM.02927-13.
Padilla-Crespo, Elizabeth, Yan, Jun, Swift, Cynthia M, Chourey, Karuna, Hettich, Robert, Ritalahti, Kirsti M, and Loeffler, Frank E. Wed . "Identification and environmental distribution of dcpA encoding the 1,2-dichloropropane-to-propene reductive dehalogenase in organohalide-respiring Chloroflexi". United States. doi:10.1128/AEM.02927-13.
@article{osti_1118749,
title = {Identification and environmental distribution of dcpA encoding the 1,2-dichloropropane-to-propene reductive dehalogenase in organohalide-respiring Chloroflexi},
author = {Padilla-Crespo, Elizabeth and Yan, Jun and Swift, Cynthia M and Chourey, Karuna and Hettich, Robert and Ritalahti, Kirsti M and Loeffler, Frank E},
abstractNote = {Dehalococcoides mccartyi (Dhc) strains KS and RC grow with 1,2-dichloropropane (1,2-D) as an electron acceptor in enrichment cultures derived from hydrocarbon-contaminated and pristine river sediments, respectively. Transcription, expression, enzymatic and PCR analyses implicated the reductive dehalogenase gene dcpA in 1,2-D dichloroelimination to propene and inorganic chloride. Quantitative real-time PCR (qPCR) analyses demonstrated Dhc cell increase during growth with 1,2-D and suggested that both Dhc strains carried a single dcpA gene copy per genome. Dhc strain RC and strain KS produced 1.8 0.1 x 107 and 1.4 0.5 x 107 cells per mole of propene formed, respectively. The dcpA gene was identified in 1,2-D-to-propene-dechlorinating microcosms established with sediment samples collected from different geographical locations in Europe and North and South America. Clone library analysis revealed two distinct dcpA phylogenetic clusters, both of which the dcpA gene-targeted qPCR assay captured, suggesting the qPCR assay is useful for site assessment and bioremediation monitoring at 1,2-D-contaminated sites.},
doi = {10.1128/AEM.02927-13},
journal = {Applied and Environmental Microbiology},
number = 3,
volume = 80,
place = {United States},
year = {Wed Jan 01 00:00:00 EST 2014},
month = {Wed Jan 01 00:00:00 EST 2014}
}
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