Prof. John R. Engen

	John R. Engen
	Bioanalytical Mass Spectrometry Faculty Fellow, Associate Professor of Chemistry & Chemical Biology The Barnett Institute 341 Mugar Life Sciences Northeastern University 360 Huntington Avenue Boston MA 02115 email: j.engen@neu.edu voice: 617-373-6046 fax: 617-373-2855 Chemistry Dept. Engen Page Engen Research Group Page

Education

1994 B.S., Molecular Biology, Union College
1995 B.S., Biochemistry, Union College
1999 Ph.D., Analytical Chemistry, University of Nebraska-Lincoln
2000 EMBO Postdoctoral Fellow, EMBL Heidelberg, Germany
2001 Postdoctoral Associate, Los Alamos National Laboratory

Research Interests

Research in the laboratory centers on the use of state-of-the-art mass spectrometry (MS) to study the conformations and movements of proteins and protein machines. Mass spectrometry can be used to study protein conformation if the proteins in question are labeled with a structure-dependent labeling method such as amide hydrogen exchange (HX). See also www.hxms.com.

Proteins contain a number of hydrogens that can exchange with hydrogen in the surrounding solvent. The most useful hydrogen to follow is the backbone amide hydrogen. If the normal H₂O solvent is changed to D₂O, the protein gradually becomes deuterated. Because deuterium and hydrogen differ in mass by 1 dalton, the incorporation of deuterium (aka, hydrogen exchange) into a protein can be monitored with high resolution mass spectrometry.

The rate of HX depends on hydrogen bonding and solvent accessibility. Folded proteins can have amino acids with HX rates as much as 1 billion times slower than the same amino acid that is not in a folded protein. Protein folding and unfolding, whether in cells or in the test tube, represent large changes in protein structure, hydrogen bonding and solvent accessibility that can be investigated with HX MS. Smaller structural changes critical for protein function can also be probed with HX MS.

Projects of current interest include: (1) the analysis of structural changes in the Src-family of tyrosine kinases during interactions with regulatory proteins and (2) the analysis of the conformational features of viral proteins that are not amenable to crystallography or NMR.

There are ongoing opportunities for undergraduate, graduate and postdoctoral research in the group. Interested people should contact Prof. Engen by email.

Selected Recent Publications See Research Page for complete listing 22.Dec.2006

	Mitchell, J.L. Trible, R.P., Emert-Sedlak, L.A., Weis, D.D., Lerner, E.C., Applen, J.J., Sefton, B.M., Smithgall, T.E. & Engen, J.R. (2007). Functional characterization and conformational analysis of the Herpesvirus saimiri Tip-C484 protein. J. Mol. Biol. in press. DOI: 10.1016/j.jmb.2006.12.026.
	Weis, D.D., Kass, I.J. & Engen, J.R. (2006). Semi-automated analysis of hydrogen exchange mass spectra using HX-Express. J. Am. Soc. Mass Spectrom., 17(12), 1700-1703. Software website: www.hxms.com/HXExpress
	Weis, D.D., Kjellen, P., Sefton, B.M., & Engen, J.R. (2006). Altered dynamics in Lck SH3 upon binding to the LBD1 domain of Herpesvirus saimiri Tip. Protein Sci. 15(10), 2402-2410.
	Meyn, M.A., Wilson, M.B., Abdi, F.A., Fahey, N., Schiavone, A.P., Wu, J., Hochrein, J.M., Engen, J.R., & Smithgall, T.E. (2006). Src-family kinases phosphorylate Bcr-Abl SH3-SH2 region and modulate Bcr-Abl transforming activity. J. Biol. Chem., 281(41), 30907-16.
	Hochrein, J.M., Wales, T.E., Lerner, E.C., Schiavone, A.P., Smithgall, T.E. & Engen, J.R. (2006). Conformational features of the full-length HIV and SIV Nef proteins by mass spectrometry. Biochemistry 45(25), 7733-7739.
	Wu, Y., Hobbins, W.B. & Engen, J.R. (2006). Ultra performance liquid chromatography (UPLC) further improves hydrogen/deuterium exchange mass spectrometry. J. Am. Soc. Mass Spectrom. 17(2), 163-167.
	Wales, T.E. & Engen, J.R. (2006). Hydrogen exchange mass spectrometry for the analysis of protein dynamics. Mass Spectrom. Rev. 25(1), 158-170.