Faculty and Staff Directory
Caryn E. Outten
|Title:||Professor and Guy F. Lipscomb Professor of Chemistry / Biochemistry and Molecular
Bioinorganic / Biophysical
|Department:||Chemistry and Biochemistry
Department of Chemistry and Biochemistry
Office: GSRC 308
Lab: GSRC 305, 803-777-4736
Lab 2: GSRC 306
Lab 3: GSRC 313
Lab 4: GSRC 320
Caryn Outten Group Website
Publications on PubMed
Department of Chemistry and Biochemistry
B.S., 1995, College of William and Mary
M.S., 1996, Northwestern University
Ph.D., 2001, Northwestern University
Honors and Awards
Garnet Apple Award for Teaching Innovation, 2016; SC Governor's Young Scientist Award for Excellence in Scientific Research, 2013; University of South Carolina Breakthrough Rising Star, 2011; Presidential Early Career Award for Scientists and Engineers (PECASE), 2009; NIEHS Transition to Independent Positions (K22) Award, 2005-08.
The goals of the C. Outten research laboratory are two-fold: we seek to understand how cells maintain adequate levels of the essential metal iron and we study how the redox-active tripeptide glutathione is distributed and used throughout the cell. By using the single-celled eukaryote Saccharomyces cerevisiae (baker’s yeast) as our primary model system, we investigate iron and glutathione metabolism using molecular genetics, protein biochemistry, and cell biology approaches.
Project 1: Iron Regulation Mechanisms. Iron is an essential nutrient that is required for a number of basic cellular functions (e.g. electron transfer, oxygen transport, enzyme catalysis). However, too much iron can be toxic due to its ability to catalyze formation of reactive oxygen species. Consequently, the process by which cells maintain iron at sufficient, non-toxic levels, known as iron homeostasis, is essential for cell survival. Human defects in iron homeostasis are common disorders that lead to anemias, muscles myopathies, mitochondrial dysfunction disorders, and hemochromatosis. We study the structure, function, and subcellular localization of iron binding proteins that play important roles in iron trafficking and regulation to better understand iron homeostasis at the cellular and molecular level. Most of the proteins we focus on bind iron as Fe-S cluster cofactors with electronic properties that allow us to monitor the metal-protein interactions and coordination chemistry using biophysical spectroscopic techniques (UV-visible absorbance, circular dichroism, electron paramagnetic resonance, etc). Our long-term goal is to provide novel insights into the basic biology of iron metabolism that will aid the prevention and treatment of human iron disorders.
Project 2: Mitochondrial Glutathione Metabolism. Our goals for this project are to identify factors that control mitochondrial redox balance and characterize the role of the tripeptide glutathione in mitochondrial function. To accomplish this, we use green fluorescent protein (GFP)-based redox sensors we developed to measure the glutathione redox state (oxidized vs. reduced) in different subcellular compartments. The mitochondrion is a specialized organelle within cells that houses numerous essential functions, including the respiratory machinery responsible for cellular energy production. Consequently, disruption of mitochondrial redox balance contributes to a host of human disorders, including cancer, neurodegenerative diseases, and aging. To better understand redox control pathways in mitochondria, we have targeted green fluorescent protein (GFP)-based redox sensors to cytosolic and mitochondrial subcellular compartments to provide a readout of redox changes in live cells. These sensors equilibrate with local glutathione (GSH) pools and register thiol redox changes via disulfide bond formation. This approach allows us to selectively monitor the redox state of subcellular compartments in real time. Our long-term goal is to characterize the subcellular impact of environmental and genetic factors on thiol redox homeostasis to more fully understand their effects on human health and disease.
Albetel AN, Outten CE. "Characterization of glutaredoxin Fe-S cluster-binding interactions using circular dichroism spectroscopy." Methods Enzymol. 2018, 599:327-353. DOI: 10.1016/bs.mie.2017.11.003.
Outten CE. "Checks and balances for the iron bank." J Biol Chem. 2017, 292(38):15990-15991. DOI: 10.1074/jbc.H117.785741.
Ponsero AJ, Igbaria A, Darch MA, Miled S, Outten CE, Winther JR, Palais G, D'Autréaux B, Delaunay-Moisan A, Toledano MB. "Endoplasmic reticulum transport of glutathione by Sec61 is regulated by Ero1 and Bip." Mol Cell. 2017, 67(6):962-973.e5. DOI: 10.1016/j.molcel.2017.08.012.
Dlouhy AC, Beaudoin J, Labbé S, Outten CE. "Schizosaccharomyces pombe Grx4 regulates the transcriptional repressor Php4 via [2Fe-2S] cluster binding." Metallomics. 2017, 9(8):1096-1105. DOI: 10.1039/c7mt00144d.
Dlouhy AC, Li H, Albetel AN, Zhang B, Mapolelo DT, Randeniya S, Holland AA, Johnson MK, Outten CE. "The Escherichia coli BolA protein IbaG forms a histidine-ligated [2Fe-2S] bridged complex with Grx4." Biochemistry. 2016, 55(49):6869-79. DOI: 10.1021/acs.biochem.6b00812.