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
Engen Research Group Page
Chemistry Dept. Engen 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 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 25.July.2008

	Conformational disturbance in Abl kinase upon mutation and deregulation. Iacob RE, Pene-Dumitrescu T, Zhang J, Gray NS, Smithgall TE, Engen JR. Proc Natl Acad Sci U S A. 2009 Feb 3;106(5):1386-91. Epub 2009 Jan 21
	Tyrosine phosphorylation in the SH3 domain disrupts negative regulatory interactions within the c-Abl kinase core. Chen S, O'Reilly LP, Smithgall TE, Engen JR. J Mol Biol. 2008 Nov 7;383(2):414-23. Epub 2008 Aug 23.
	Ion mobility adds an additional dimension to mass spectrometric analysis of solution-phase hydrogen/deuterium exchange. Iacob RE, Murphy JP 3rd, Engen JR. Rapid Commun Mass Spectrom. 2008 Sep;22(18):2898-904.
	High-speed and high-resolution UPLC separation at zero degrees Celsius. Wales TE, Fadgen KE, Gerhardt GC, Engen JR. Anal Chem. 2008 Sep 1;80(17):6815-20. Epub 2008 Aug 2
	Engen J.R., Wales T.E., Hochrein J.M., Meyn M.A. 3rd, Ozkan S.B., Bahar I. & Smithgall T.E. (2008). Structure and Dynamic Regulation of Src-Family Kinases. Cell Mol Life Sci. in press. DOI: 10.1007/s00018-008-8122-2
	Chen S., Dumitrescu T.P., Smithgall T.E. & Engen J.R. (2008) Abl N-terminal Cap stabilization of SH3 domain dynamics. Biochemistry 47(21), 5795-5803.
	Brier S., Engen J.R. (2008). Hydrogen Exchange Mass Spectrometry: Principles and Capabilities. In “Mass Spectrometry Analysis for Protein-Protein Interactions and Dynamics", 2008. pp 11-43. ISBN: 978-0-470-25886-6, Blackwell Publishing, Mark R. Chance, Editor.
	Brier, S., Maria, G., Carginale, V., Capasso, A., Wu, Y., Taylor, R.M., Borotto, N.B., Capasso, C. & Engen, J.R. (2007). Purification and characterization of pepsins A1 and A2 from the Antarctic rock cod Trematomus bernacchi. FEBS J. 274(23), 6152-6166.
	Trible, R.P., Emert-Sedlak, L., Wales, T.E., Ayyavoo, V. Engen, J.R. & Smithgall, T.E. (2007). Allosteric loss-of-function mutations in HIV-1 Nef from a long-term non-progressor. J. Mol. Biol. 374(1), 121-129.
	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.

Last Updated 10/20/09