Corexit 9500 Enhances Oil Biodegradation and Changes Active Bacterial Community Structure of Oil-Enriched Microcosms

To better understand the impacts of Corexit 9500 on the structure and activity levels of hydrocarbon-degrading microbial communities, we analyzed next-generation 16S rRNA gene sequencing libraries of hydrocarbon enrichments grown at 5 and 25°C using both DNA and RNA extracts as the sequencing templa...

Full description

Saved in:
Bibliographic Details
Published in:Applied and environmental microbiology 2017-05, Vol.83 (10), p.E03462
Main Authors: Techtmann, Stephen M, Zhuang, Mobing, Campo, Pablo, Holder, Edith, Elk, Michael, Hazen, Terry C, Conmy, Robyn, Santo Domingo, Jorge W
Format: Article
Language:English
Subjects:
Abundance
Alcanivorax
Aromatic compounds
Bacteria
Bacteria - classification
Bacteria - drug effects
Bacteria - genetics
Bacteria - metabolism
BASIC BIOLOGICAL SCIENCES
Biodegradation
Biodegradation, Environmental
Colwellia
Communities
Community structure
Consortia
Cycloclasticus
Degradation
Deoxyribonucleic acid
DNA
DNA sequencing
Enrichment
Environmental Microbiology
Flavobacterium
Gene sequencing
Hydrocarbon-degrading bacteria
Hydrocarbons - metabolism
Idiomarina
Lipids - pharmacology
Marinobacter
Microbial activity
Microcosms
Microorganisms
Oil
Oil spills
Petroleum - metabolism
Petroleum Pollution - analysis
Phylogeny
Relative abundance
Ribonucleic acid
RNA
rRNA 16S
Solvents
Vibrio
Waterborne diseases
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:To better understand the impacts of Corexit 9500 on the structure and activity levels of hydrocarbon-degrading microbial communities, we analyzed next-generation 16S rRNA gene sequencing libraries of hydrocarbon enrichments grown at 5 and 25°C using both DNA and RNA extracts as the sequencing templates. Oil biodegradation patterns in both 5 and 25°C enrichments were consistent with those reported in the literature (i.e., aliphatics were degraded faster than aromatics). Slight increases in biodegradation were observed in the presence of Corexit at both temperatures. Differences in community structure were observed between treatment conditions in the DNA-based libraries. The 25°C consortia were dominated by , , , , and species, while the 5°C consortia were dominated by several species of the genera , , and Most of these genera have been linked to hydrocarbon degradation and have been observed after oil spills. and , known aromatic degraders, were also found in these enrichments. The addition of Corexit did not have an effect on the active bacterial community structure of the 5°C consortia, while at 25°C, a decrease in the relative abundance of was observed. At 25°C, , , and were present at higher relative abundances in the RNA than DNA libraries, suggesting that they were active in degradation. Similarly, was greatly stimulated by the addition of oil at 5°C. While dispersants such as Corexit 9500 can be used to treat oil spills, there is still debate on the effectiveness on enhancing oil biodegradation and its potential toxic effect on oil-degrading microbial communities. The results of this study provide some insights on the microbial dynamics of hydrocarbon-degrading bacterial populations in the presence of Corexit 9500. Operational taxonomic unit (OTU) analyses indicated that several OTUs were inhibited by the addition of Corexit. Conversely, a number of OTUs were stimulated by the addition of the dispersant, many of which were identified as known hydrocarbon-degrading bacteria. The results highlight the value of using RNA-based methods to further understand the impact of dispersant on the overall activity of different hydrocarbon-degrading bacterial groups.
ISSN:0099-2240
1098-5336
DOI:10.1128/AEM.03462-16