Megan McEvoy
Assistant Professor of Biochemistry and Molecular Biophysics
Ph.D. 1997, University of Oregon, Eugene
Structure/Function Relationships in Proteins; Metal Resistance and Homeostasis
Research Interests
Research in the McEvoy lab uses a combination of biochemical and biophysical approaches to address protein structure/function relationships in microbial metal resistance systems. Metals are required at low intracellular levels for proper cellular function. However environments with high metal concentrations can be lethal unless cells can regulate the levels of metals within the cell. Humans have taken advantage of the toxicity of metals and have used metals as antimicrobials in a wide variety of settings, though increasing numbers of organisms have been discovered with metal resistance systems that allows their survival in environments with high concentrations of metals.
One type of metal resistance system we have been studying is an export complex, the Cus system, which spans both the inner and outer membranes of gram-negative bacteria. This system is involved in copper and silver resistance in the bacterium E. coli, which provides an excellent model system to study metal transport and homeostasis. Our approaches to studying this system include biochemical characterization as well as structural characterization using NMR spectroscopy and x-ray crystallography. We are seeking to understand the molecular mechanism of this metal efflux system by determining the structures of the components and characterizing their interactions with each other and with metals.
Selected Publications
D. Quaranta, M. M. McEvoy, & C. Rensing (2009). Site Directed Mutagenesis Identifies a Molecular Switch Involved in Copper Sensing by the Histidine Kinase CinS in Pseudomonas putida KT2440. Journal of Bacteriology, Jun 19, epub ahead of print.
I. Loftin, N. J. Blackburn, & M. M. McEvoy (2009). Tryptophan Cu(I)-pi Interaction Fine-tunes the Metal Binding Properties of the Bacterial Metallochaperone CusF. Journal of Biological Inorganic Chemistry, April 21, epub ahead of print.
I. Bagai, C. Rensing, N. J. Blackburn, & M. M. McEvoy (2008). Direct Metal Transfer between Periplasmic Proteins Identifies a Bacterial Copper Chaperone. Biochemistry, 47, 11408.
I. Bagai, W. Liu, C. Rensing, N. J. Blackburn, & M. M. McEvoy (2007). Substrate-linked Conformational Change in the Periplasmic Component of a Cu(I)/Ag(I) Efflux System. Journal of Biological Chemistry, 282, 35695-35702.
I. Bagai, W. Liu, C. Rensing, N. J. Blackburn, & M. M. McEvoy (2007). Substrate-linked Conformational Change in the Periplasmic Component of a Cu(I)/Ag(I) Efflux System. Journal of Biological Chemistry, 282, 35695-35702.
I. R. Loftin, S. Franke, N. J. Blackburn, & M. M. McEvoy (2007). Unusual Cu(I)/Ag(I) Coordination of Escherichia coli CusF as Revealed by Atomic Resolution Crystallography and X-ray Absorption Spectroscopy. Protein Science 16, 2287-2293.
Kittleson, J.T., I.R. Loftin, A.C. Hausrath, K.P. Engelhardt, C. Rensing, & M.M. McEvoy (2006). Periplasmic metal-resistance protein CusF exhibits high affinity and specificity for both CuI and AgI. Biochemistry 45: 11096-11102.
Loftin IR, Franke S, Roberts SA, Weichsel A, Heroux A, Montfort WR, Rensing C, McEvoy MM. A Novel Copper-Binding Fold for the Periplasmic Copper Resistance Protein CusF. Biochemistry. 2005 Aug 9;44(31):10533-10540.
Astashkin, A.V., A.M. Raitsimring, F.A. Walker, C. Rensing, and M.M. McEvoy (2005). Characterization of the copper(II) binding site in the pink copper binding protein CusF by electron paramagnetic resonance spectroscopy. Journal of Biological Inorganic Chemistry 10: 221-230.
Dyer, C.M., M.L. Quillin, A. Campos, J. Lu, M.M. McEvoy, A.C. Hausrath, E.M. Westbrook, P. Matsumura, B.W. Matthews, and F.W. Dahlquist (2004). Structure of the Constitutively Active Double Mutant CheYD13K Y106W Alone and in Complex with a FliM Peptide. Journal of Molecular Biology 342: 1325-1335.