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High-Resolution Respirometry to Assess Bioenergetics in Cells and Tissues Using Chamber- and Plate-Based Respirometers
Published on: October 26, 2021
Genomic insights into organohalide respiration
1School of Civil and Environmental Engineering, Cornell University, Ithaca, NY 14853, United States. Rer26@cornell.edu
Current Opinion in Biotechnology
|March 16, 2013
Summary
Genome sequencing reveals obligate organohalide-respiring bacteria (OHRB) possess numerous reductive dehalogenase genes, likely acquired through transposition. This advances bioremediation strategies for chlorinated contaminants.
Area of Science:
- Microbiology
- Environmental Science
- Genomics
Background:
- Organohalide-respiring bacteria (OHRB) are crucial for bioremediation of chlorinated pollutants.
- Recent genome releases have expanded our understanding of OHRB diversity and function.
Purpose of the Study:
- To analyze newly released genomes of OHRB, focusing on genera like Dehalococcoides, Dehalogenimonas, and Dehalobacter.
- To investigate the genetic basis for organohalide respiration (OHR) and identify potential mechanisms for dehalogenase gene acquisition.
Main Methods:
- Comparative genomic analysis of OHRB genomes.
- Identification and characterization of reductive dehalogenase (RDase) genes and associated genetic elements.
Main Results:
- Obligate OHRB genomes (Dehalococcoides, Dehalogenimonas, Dehalobacter) contain 10-39 unique RDase genes.
- These RDase genes are often flanked by transcriptional regulators and transposition-related genes, suggesting active gene shuffling.
- Other OHRB genera (e.g., Desulfitobacterium, Geobacter) utilize OHR as one of several metabolic strategies.
Conclusions:
- The genetic architecture of obligate OHRB genomes supports their specialized role in dehalogenation.
- Transposition likely drives the expansion and regulation of dehalogenase gene repertoires in OHRB.
- Functional assays are needed to determine the substrate ranges of newly discovered dehalogenases.
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