Teresa Thiel, Ph.D.

Research Interests: hydrogen production, nitrogen fixation, cyanobacteria, symbiosis, metal transport, gene regulation.

My research is in the area of microbiology and molecular biology, specifically on nitrogen fixation, hydrogen production and gene regulation in filamentous cyanobacteria, both in free-living and in symbiotic associations with plants.

• We study three sets of genes that encode the proteins requires for three independent nitrogenases that convert atmospheric nitrogen to ammonia and also produce hydrogen from sunlight and water. We are working to understand the molecular mechanisms that control the differential expression of the three sets of genes, including the role of environmental factors, including metal ions.
• We are investigating the feasibility of genetically modifying cyanobacteria for the commercial production of hydrogen gas for fuel cells that can be used to power automobiles in the future. This includes the study of cyanobacterial hydrogen producing enzymes as well the introduction of hydrogenases from other bacteria into Anabaena.
• We are interested in the roles of metals, especially metal cofactors, such as molybdenum and vanadium, in the control of gene expression in Anabaena.
• We are studying the factors that regulate the symbiotic relationship between the nitrogen fixing cyanobacterium, Nostoc, and plant cells, particularly the liverwort Blasia.

Recent Publications

Vernon, S.A., Pratte, B.S, and Thiel T. 2016. Role of the nifB1 and nifB2 promoters in cell-type-specific expression of two Mo-nitrogenases in the cyanobacterium Anabaena variabilis ATCC 29413.

Pratte, B. S. and Thiel, T. 2016, Homologous regulators, CnfR1 and CnfR2, activate expression of two distinct nitrogenase gene clusters in the filamentous cyanobacterium Anabaena variabilis ATCC 29413. Molecular Microbiology, 100: 1096–1109. doi:10.1111/mmi.13370 

Pratte, B.S., Ungerer, J. and Thiel, T. 2015. The role of RNA secondary structure and processing in stability of the nifH1 transcript in the cyanobacterium Anabaena variabilis.J. Bacteriol. 192:13 3311-3320.

Thiel, T, and Pratte B.S. 2014. Regulation of three nitrogenase gene clusters in the cyanobacterium Anabaena variabilis ATCC 29413. Life 4:944-967.

Thiel, T, Pratte B.S., Zhong J., Goodwin L., Copeland A., Lucas S., Han C., Pitluck S., Land M.L., Kyrpides N.C, and Woyke T. 2014.Complete genome sequence of Anabaena variabilis ATCC 29413. Standards in Genomic Research. 9:3. 

Pratte, B. and Thiel, T. 2014. Regulation of nitrogenase gene expression by transcript stability in the cyanobacterium  Anabaena variabilis. J. Bacteriol. 196:3609-3621.

Thiel, T, Pratte B.S. 2013. Alternative nitrogenases in Anabaena variabilis: The role of molybdate and vanadate in nitrogenase gene expression and activity. Advances in Microbiology. 3:87-95.

Sheridan, R., Pratte, B.S., and Thiel, T. 2013  Regulation of the V-nitrogenase genes in Anabaena variabilis by RNA processing and by dual repressors. Mol Microbiol 88:413-424.

Duggan, P.S., Thiel, T., and Adams, D.G. 2013. Symbiosis between the cyanobacterium Nostoc and the liverwort Blasia requires a CheR-type MCP methyltransferase. Symbiosis 59:111-120.

Ungerer, J., Pratte, B.S., and Thiel, T. 2010. RNA processing of nitrogenase transcripts in the cyanobacterium Anabaena  variabilis.  J. Bacteriol. 192:3311-3320. (Abstract/FREE Full Text)

Ungerer, J., Pratte, B.S., and Thiel, T. 2008. Regulation of fructose transport and its effect on fructose toxicity in Anabaena spp.  J. Bacteriol. 190:8115-8125. (pdf file)

Weyman, P.D., Pratte, B. and Thiel, T.  2008. Transcription of hupSL is regulated by NtcA and not by hydrogen in Anabaena variabilis ATCC 29413. Applied Environ. Microbiol. 74: 2103-2110. (pdf file)

Shearn-Bochsler, V.,  Green,  D. E., Converse,  K.A., Docherty, D.E., Thiel, T., Geisz, H. N.; Fraser, William R.; Patterson-Fraser, Donna L.  2008. Avian poxvirus infection in a nestling Southern Giant Petrel (Macronectes giganteus) from Antarctica. Polar Biol. 31:569–573. (pdf file)

Thiel, T., and Pratte, B., 2006. High-affinity vanadate transport system in the cyanobacterium Anabaena variabilis ATCC 29413. J. Bacteriol. 188:464-468.

Pratte, B., Eplin, K., and Thiel, T. 2006.  Cross-functionality of NifH1 and VnfH in nitrogen fixation in Anabaena variabilis. J. Bacteriol. 188: 5806-5811.

Thiel, T. 2006. Nitrogenase, Hydrogenase and Hydrogen Production by Cyanobacteria. In: Singh, S. (ed). Micro-algal Biotechnology. Pvt.Ltd, New Delhi,India. 

Thiel, T., Whiteman, N.K. Tirapé, A., Ines-Baquero, M., Cedeño, V., Walsh, T, Jiménez-Uzcátegui, G. and Parker, P.G. 2005. Characterization of Canarypox-like Viruses Infecting Endemic Birds in the Galápagos Islands.  J. Wildl. Dis. 41:342-353.

Thiel, T. 2004. Nitrogen Fixation in Heterocyst-Forming Cyanobacteria. 2004. pp. 73-110. Chapter 5. In: W. Klipp, B. Masepohl, J.R. Gallon & W.E. Newton (eds.), Genetics andRegulation of Nitrogen Fixing Bacteria. Kluwer Academic Publishers, Printed in the Netherlands.

Zahalak, M., Pratte, B., Werth, K.J., and Thiel, T. 2004. Molybdate transport and its effect on nitrogen utilization in the cyanobacterium Anabaena variabilis ATCC 29413. Molec. Microbiol. 51: 539-550.

Thiel T, Pratte B, Zahalak M. Transport of molybdate in the cyanobacterium Anabaena variabilis ATCC 29413. Arch Microbiol. 179:50-56 (2002).

Meeks. J. C., Elhai, J., Thiel, T., Potts, M., Larimer, F, Lamerdin, J., Predki, P. and R. Atlas. An overview of the genome of Nostoc punctiforme, a multicellular, symbiotic cyanobacterium. Photosynthesis Research. 70:85-106 (2002). 

Thiel, T., Meeks, J.C, Elhai, J., Potts, M., Larimer, F., Lamerdin, J., Predki, P., and R. Atlas. Nitrogen Fixation: analysis of the genome of the Nostoc punctiforme. in: Nitrogen Fixation: Global Perspectives. Edited by Finan, T.M, O'Brian, M.R., Layzell, D.B., Vessey, J.K, and Newton, W. CABI Publishing. New York. pp. 88-92. (2002).

Thiel, T. and B. Pratte. Effect on heterocyst differentiation of nitrogen fixation in vegetative cells of the cyanobacterium Anabaena variabilis ATCC 29413. J. Bacteriol. 183: 280-286. (2001).

Thiel, T. Genetics and regulation of multiple nitrogenases in the cyanobacterium Anabaena variabilis ATCC 29413. pp. 1-27. In: Cyanobacterial and Algal Metabolism and Environmental Biotechnology. Edited by T. Fatma. Phycological Society. India. (1999).

Thiel, T., Liczkowski, L., and S.T. Bissen. New zwitterionic butanesulfonic acids that extend the alkaline range of four families of Good buffers: evaluation for use in biological systems. J. Biochem. Biophys. Meth. 37: 117-129. (1998).

Thiel, T., Lyons, E.M., and Thielemier, J. Organization and regulation of two clusters of nif genes in the cyanobacterium Anabaena variabilis. pp. 517-521. In: Phototrophic Prokaryotes. Edited by G.A. Peschek, W. Loeffelhardt, and G. Schmetterer. Plenum Press, N.Y. (1998).

Heinlein, M., Wood, M.R., Thiel, T., and R.N. Beachy. Targeting and modification of prokaryotic cell-cell junctions by tobacco mosaic virus cell-to-cell movement protein. Plant J. 14: 345-351. (1998).

Thiel, T., Lyons, E.M. and J.C. Erker. Characterization of genes for a second Mo-dependent nitrogenase in the cyanobacterium Anabaena variabilis. J. Bacteriol. 179:5222-5225. (1997). 

Thiel, T., Lyons, M., and M. Zahalak. Regulation of alternative nitrogenase systems by environmental factors in the cyanobacterium Anabaena variabilis. In Bothe, H. (ed.) Biological Fixation of Nitrogen for Ecology and Sustainable Agriculture. NATO ASI ser. G.Springer Verlag. pp. 159-162. (1997).

Thiel, T. Isolation and characterization of the vnfEN genes of the cyanobacterium Anabaena variabilis. J. Bacteriol.178:4493-4499 (1996). 

Thiel, T., Lyons, E. M., Erker, J. C. and A. Ernst. A second nitrogenase in vegetative cells of a heterocyst-forming cyanobacterium. Proc. Natl. Acad. Sci. U.S.A. 92:9358-9362. (1995). 

Zahalak, M., Beachy, R.N., and T. Thiel. Expression of the movement protein of tobacco mosaic virus in the cyanobacterium Anabaena sp. PCC 7120. Molecular Plant Microbe Interactions. 8:192-199 (1995).

Lyons, E. and T. Thiel. Characterization of nifB, nifS, and nifU mutants of the cyanobacterium Anabaena variabilis: NifB is required for the V-dependent nitrogenase. J. Bacteriol. 177:1570-1575. (1995).

Thiel, T. Genetic analysis of cyanobacteria. In: Bryant, D.A. (Ed.) The Molecular Biology of the Cyanobacteria. Kluwer AcademicPress. Dordrecht, The Netherlands pp. 581-611. (1994).

Thiel, T. Characterization of genes for an alternative nitrogenase in the cyanobacterium Anabaena variabilis. J. Bacteriology 175:6276-6286. (1993).