Dr. Elise R. Sullivan
Ph.D., University of Maryland, 1999
Marine Microbiology
Using an ecological approach to study bacteria I have looked at very diverse environments where bacteria live, ranging from groundwater samples taken from deep cores in the earth, to the shell of a lobster, to highly acidic vats at a vinegar production plant. Students in my lab have explored the community diversity as well as identified active members using techniques that include fluorescence microscopy, electron microscopy, DNA fingerprinting (DGGE), gas chromatography (GC), and flow cytometry. Currently, I am working on two areas of research in my laboratory:
Microbial degradation of pollutants.
Although different organisms are known to degrade various pollutants ranging from highly chlorinated chemicals to oily petroleum products, we don’t fully understand the mechanisms involved and whether these organisms are active at a contaminated site. One of my projects is to determine the abundance of key members of the microbial population within trichloroethene (TCE) contaminated bedrock, and monitor whether their numbers increase as a result of bioremediation efforts. Another project examines how bacteria ingest oily pollutants for food, since these hydrophobic substrates are difficult to move into the hydrophilic interior of the cell. Our ultimate goal is to better understand the microbiology of contaminated sites to improve bioremediation practices.
Microbiology of lobster shell disease.
The American lobster is the single most important commercial fishery in New Hampshire. The animal is susceptible to shell disease, which causes lesions on the lobster’s exoskeleton that reduce their market value. Recent statistics show that prevalence of shell disease has increased dramatically in New England over the past few years. The cause of shell disease has not yet been determined. My goal is to determine the normal microbiota of lobsters and compare how it differs from diseased animals. By determining what microbe(s) are responsible for lobster shell disease we will be better able to know how to protect this valuable natural resource.
Both research projects focus on studying microbial communities in their natural environment, rather than taking a more classical approach of working with single organisms in pure culture. With the set of tools we currently use, there is an endless possibility of other microbial communities we may explore in the future.
Publications:
- Snellman, E.A., Sullivan, E.R., and Colwell, R.R. 2002. Purification and properties of the extracellular lipase, LipA, of Acinetobacter sp. RAG-1. Eur. J. Biochem. 269:5771-5779.
- Sullivan, E.R., Zhang, X., and Young, L.Y. 2001. Anaerobic mineralization of stable-isotope-labeled 2-methylnaphthalene. Appl. Environ. Microbiol. 67:4353-4357.
- Zhang, X., Sullivan, E.R. and Young, L.Y. 2000. Evidence for aromatic ring reduction in the biodegradation pathway of carboxylated naphthalene by a sulfate reducing consortium. Biodegradation, 11:117-124.
- Sullivan, E.R., Leahy, J.G. and Colwell, R.R. 1999. Cloning and sequence analysis of the lipase and lipase chaperone genes from Acinetobacter calcoaceticus RAG-1, and redefinition of a proteobacterial lipase family and an analogous lipase chaperone family. Gene, 230:277-285.
- Vaneechoutte, M., Tjerberg, I., Baldi, F., Pepi, M., Fani, R., Sullivan, E.R., van der Toorn, J. and Dijkshoorn, L. 1999. The oil-degrading Acinetobacter strain RAG-1 and the strain described as Acinetobacter venetianus sp. nov. belong to the same genomic species. Res. Microbiol. 150:69-73.
- Sullivan, E.R. 1998. Molecular genetics of biosurfactant production. Curr. Opin. Biotechnol. 9:263-269.
