Grantee Research Project Results

Potential for the Sea Ice Microbial Community to Bioremediate Crude Oil

EPA Grant Number: FP917310
Title: Potential for the Sea Ice Microbial Community to Bioremediate Crude Oil
Investigators: Bowman, Jeff S
Institution: University of Washington
EPA Project Officer: Packard, Benjamin H
Project Period: September 6, 2011 through September 5, 2014
Project Amount: $126,000
RFA: STAR Graduate Fellowships (2011) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Fellowship - Emerging Environmental Approaches and Challenges: Innovative Investigations for Oil Spill Impacts

Objective:

This study has three objectives: (1) establish a baseline of microbial community structure and composition within sea ice, including members of the rare biosphere who may have bioremediation potential; (2) search for genes known to be involved in the degradation of crude oil within several different components of the sea ice environment; and (3) determine the prevalence of these genes within the active segment of the microbial community.

Approach:

DNA will be extracted from samples of first year ice, young sea ice, marine water and surface ice features (known to be microbial enriched) from McMurdo Sound, Antarctica. Pending additional field opportunities, samples also may be collected from Barrow, Alaska or Nuuk, Greenland. Purified DNA from these samples will be amplified for the V6 hypervariable region of the 16S rRNA gene and sequenced in a massively parallel fashion using the paired-end technique on either the SOLiD or Illumina sequencing platforms. Both of these platforms support sufficient multiplexing to allow replication, yet still allow for great sequencing depth (tens of millions of reads per sample). Taxonomic and phylogenetic analysis of assembled paired-ends, and community description with standard ecological indices will establish a valuable baseline of the sea ice microbial community. Amplification of the purified DNA with primers specific to genes marking known pathways for the degradation of crude oil components, followed by clone library and T-RFLP analysis will characterize the bioremediation potential of the sea ice microbial community. Amplification of these same genes from sea ice microcosms labeled with heavy carbon substrates (stable isotope probing, or SIP) will determine to what extent these genes are contained within an active segment of the microbial community, and thus are available for rapid bioremediation.

Expected Results:

Due to the concentrating effects of eutectic freezing, sea ice brines are considered to be an organic rich environment. Microbes adapted to life in sea ice should be capable of living under these conditions and degrading a wide range of organic compounds. Because of this, the expectation is to find that the sea ice microbial community is able to consume a broad range of organic compounds found in crude oil. If this is the case, then sea ice might serve as the seedbank for a community of oil degrading organisms in the case of an oil spill at high latitudes.

Potential to Further Environmental Human Health Protection

Increasing oil exploration in the Arctic, and the potential for exploration in the Antarctic, raise the risk of a release of crude oil in ice covered seas. This project provides valuable information on the potential of the sea ice microbial community to bioremediate released crude oil.

Supplemental Keywords:

sea ice bacteria, bioremediation, stable isotope probing, Arctic oil exploration

Progress and Final Reports:

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.