The major focus of my research effort at this time is development of new tools to investigate metal toxicology. Since heavy metals are persistent and accumulate in ecosystems, humanity’s growing reliance on metal resources compels the development of new tools to investigate metal toxicology. Elucidation of biologically relevant heavy metal binding motifs is fundamentally critical to toxicological assessment. My research group is specifically interested in the development of new NMR methods for toxicological assessment.

     An estimated 30-50% of all proteins require interaction with a metal ion for full physiological activity.  In general, metal ion binding sites are formed by the cooperative, simultaneous interaction of a number of ligating protein groups leading to considerable metal specificity. However, when challenged with non-essential metal ions, it is possible to replace native metal ions leading to physiologically detrimental changes in protein activity. 

     Cd(II), Hg(II) and Pb(II) are toxic metal ions which often dramatically alter the activity of enzymes and possess one or more isotope with favorable NMR properties.  To begin development of NMR methods that can be used for toxicological assessment, the coordination chemistry of polydentate ligands containing donors which simulate ligation by amino acid side chain donors are being characterized with these metals by multinuclear NMR. In addition, we have recently begun to investigate the mercury coordination properties of cyclic dipeptides of histidine and methionine.  The goal of these studies is to elucidate patterns in both chemical shifts and coupling constants that can be correlated with the geometry, coordination number, and identity of ligands in the primary coordination sphere of of these metals.

     In the past twelve years, over 50 new complexes of Hg(II) involving fifteen different ligand systems have been prepared in my lab and structurally characterized by X-ray crystallography (through collaborations with Marj Kastner at Bucknell University, Raymond Butcher at Howard University and Robert Pike internally).  Most of these complexes have been correlated with solution state NMR data.  Significantly, many of these complexes have demonstrated slow-exchange behavior in solution on the NMR time scale which has rarely been observed for small coordination compounds of Hg(II).  Furthermore, we have been able to measure heteronuclear coupling constants between ¹⁹⁹Hg and ¹H which are comparable in magnitude to those measured for mercury-substituted proteins. We have also conducted comparable studies with a number of Cd(II) complexes.

      In addition to the mercury coordination chemistry studies, my research group recently began investigating the catalytic potential of silica immobilized copper complexes. At this time, the effect of the pH of immobilization on peroxidase and catechol oxidase activity is under investigation. 

Selected Research Highlights:
• first example of following a conformational change in an organic ligand by monitoring of heteronuclear coupling between ligand protons and a metal (Inorg. Chem. 1998, 37, 4641). 
• first systematic comparison of ¹⁹⁹Hg and ^111/113Cd proton coupling constants in isostructural complexes (Inorg. Chem. 1999, 38, 1126).
• first observation of coupling between ¹⁹⁹Hg and ¹H over five bonds in a Hg(II) coordination compound (Inorg. Chem. 2002, 41, 2529). 
• first observation of slow exchange on the chemical shift time scale between five coordination complexes of Hg(II) (Inorg. Chem. 2002, 41, 2529).
• first observation of slow exchange on the J(¹H¹⁹⁹Hg) time scale for a complex of Hg₂²⁺ (J. Chem. Crystallog. 2003, 33, 455).

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External Funding

“Mechanistic Comparison of Evolutionarily Divergent Peptidyl alpha-Hydroxylating Monooxygenases”
 Jeffress Memorial Trust
 1/1/95 - 12/31/97
 $26,000 (Original award $16,000 & $10,000 renewal)

“Investigation of Mechanism-Based Inhibition of Peptidyl alpha-Amidating Monooxygenase” (with undergraduate Rebecca L. Casaubon)
 Council on Undergraduate Research Summer Opportunity for Research
 6/1/96 - 8/15/96
 $3,200 (student stipend & living expenses).

“Structure-Spectroscopy Correlations of Multidentate Hg(II) Complexes” 
 Petroleum Research Foundation Type GB 
 9/1/96 - 8/31/98
 $20,000. 

“Development of a Novel Probe of Metal-Protein Interactions During Protein Folding Transitions” 
 Research Corporation Cottrell College Science Awards
 1/1/98 - 12/31/99
 $28,952

“Novel ¹⁹⁹Hg NMR Methods for Monitoring Protein Folding”
 National Institutes of Health - Academic Research Enhancement Award
 6/1/99 - 5/31/04
 $107,200

“Investigation of Silica Supported Copper Complexes as Biomimetics of Mononuclear Monooxygenases” 
 Jeffress Memorial Trust
 5/28/01 - 9/30/04
 $49,825 (Original award $29,825 and two $10,000 renewals)

“Extending the Reach of ¹⁹⁹Hg NMR as a Metallobioprobe”
 Camille and Henry Dreyfus Scholar Fellow Program for Undergraduate Institutions
 6/1/03 - 05/30/06
 $100,000

“Exploring the metal biochemistry of Hg(II) with multidentate mixed N,S-donor ligands by X-ray crystallography and NMR Spectroscopy”
 Petroleum Research Fund
 9/1/03 - 8/31/06
 $50,000

“Foundations for Toxicological Studies: Probing Speciation and Structure of Cd(II), Hg(II) and Pb(II) with Multidentate Chelating Ligands”
 National Science Foundation
 09/01/03 – 08/31/06
 $180,000

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Publications

Bold = Undergraduate; Italics = Master's Student

D. C. Bebout, D. E. Ehmann, J. C. Trinidad, K. K. Crahan, M. E. Kastner,  and D. A. Parrish “Preparation of Hg(II) Complexes of Tris[(2-pyridyl)-methyl]amine and Characterization by X-ray Crystallography and NMR Spectroscopy” Inorg. Chem. 1997, 36, 4257-4264.

D. C. Bebout, D. E. Ehmann, A. E. DeLanoy, M. E. Kastner,  D. A. Parrish, R. J. Butcher “Characterization of Hg(II) Complexes of Bis[(2-pyridyl)methyl]amine and by X-ray Crystallography and NMR Spectroscopy” Inorg. Chem.1998, 37, 2952-2959.

D. C. Bebout, J. F. Bush II, K. K. Crahan, M. E. Kastner, D. A. Parrish “Correlation of a Solution State Conformational Change between Mercuric Chloride Complexes of Tris[(2-(6-methylpyridyl))-methyl]amine with X-ray Crystallographic Structures” Inorg. Chem. 1998, 37, 4641-4646.

D. C. Bebout, S. W. Stokes, R. J. Butcher “Comparison of Heteronuclear Coupling Constants for Isostructural Nitrogen Coordination Compounds of ^111/113Cd and ¹⁹⁹Hg”, Inorg. Chem. 1999, 38, 1126-1133.

D. C. Bebout, J. F. Bush II, K. K. Crahan; E. V. Bowers, R. J. Butcher “Sterically Demanding Multidentate Ligand Tris[(2-(6-methylpyridyl)methyl]amine Slows Exchange and Enhances Solution State Ligand Proton NMR Coupling to ¹⁹⁹Hg(II)” Inorg. Chem. 2002, 41, 2529. 

D. C. Bebout, J. F. Bush II, E. M. Shumann, J. A. Viehweg, M. E. Kastner; D. A. Parrish, S. M. Baldwin “Caging the Mercurous Ion: A Tetradentate Tripodal Nitrogen Ligand Enhances Stability and J(¹H¹⁹⁹Hg),” J. Chem. Cryst. 2003, 33, 455-462.

D. C. Bebout, G. S. Murphy, M. M. Garland, E. V. Bowers, R. J. Butcher “Investigation of the Mercury(II) Coordination Chemistry of Tris[(1-methylimidazol-2-yl)methyl]amine by X-ray Crystallography and NMR,” Dalton Trans. 2003, 2578-2584.

D. C. Bebout “Mercury: Inorganic and Coordination Chemistry” Encyclopedia of Inorganic Chemistry, 2nd edition, 2005, in print.

S. M. Berry, D. C. Bebout, R. J. Butcher “Solid state and solution state coordination chemistry of the zinc triad with the mixed N,S donor ligand bis(2-methylpyridyl)sulfide” Inorg. Chem. 2005, 44, 27-39.

M. M. Makowska-Grzyska, K. Doyle, R. A. Allred, E. Szajna, A. M. Arif, D. C. Bebout and L. M. Berreau “Structural, Spectroscopic and Reactivity Properties of N₂S₂(thioether)O(amide)-Ligated Hg(II) Complexes: The First Examples of Hg(II)-mediated Amide Cleavage,” Eur. J. Inorg. Chem. 2005, 822-827.

W. Lai, S. M. Berry, D. C. Bebout and R. J. Butcher “Investigation of Group 12 Metal Complexes with a Tridentate SNS Ligand by X-ray Crystallography and ¹H NMR” Inorg. Chem. accepted pending revisions.

D. C. Bebout and S. M Berry "Probing Mercury Complex Speciation with Multinuclear NMR" Structure and Bonding: Recent Developments in Mercury Science, manuscript in preparation.

W. Lai, S. M. Berry, D. C. Bebout and R. J. Butcher “ Comparison of Zinc Triad Metal Complexes of N-(2-pyridylmethyl)-N-(2-(methylthio)ethyl)amine in the Solid- and Solution-State", manuscript in preparation.
 

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Research Students

Current Students
 

Brad Carra Chemistry Honors Candidate	Katie Dunn Senior Research Assistant	John-Andrew Hocker Sophomore Research Assistant
Class of 2006	Class of 2006	Class of 2008
Daniel Tice Sophomore Research Assistant	Cyrus Wegbreit Sophomore Research Assistant	Bejamin Winer Sophomore Research Assistant
Class of 2008	Class of 2008	Class of 2008

Former Students

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Teaching Highlights

My teaching assignments at William and Mary have included courses in Biochemistry and Organic Chemistry as well as courses for non-majors. I am also an active participant in the various research programs offered by the department. Recent syllabi are linked to selected courses.
 

Courses	Enrollment	Semesters Instructed
Chem 150W Freshman Seminar:              Drugs: Panacea or Scourge	15	F ‘02, '04, '05
Chem 252 Chemistry Lab II (Organic) Chem 353 Chemistry Lab III (Organic)	-- 75	(In charge w/o session S '03, '04) F '94-'96 (In charge w/o session F ’99, ’00, ’02)
Chem 414 Biochemistry	20-120	S ’00, ‘03, '04, 05
Chem 415 Advanced Biochemistry	15-25	F ’93 - ’97, S ’99, F ’99 – ’00
Chem 420 Biochemistry Lab	3-8	S ’94 - ’99, F ’00

Additional courses no longer offered by the department: 
Survey of Organic and Biological Chemistry (S ‘97 - ’98)
Special Topics Courses (cross-listed with Biology and co-instructed with Biology faculty indicated)
           Metalloproteases (S ’95; D. Reilly)
           Angiogenic and Vascular Control Factors (S ’96; M. Saha)
           Novel Signalling Molecules (S ‘ 97; S. Broadwater)

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Former Camille & Henry Dreyfus Postdoctoral Fellow

Steven M . Berry 

Camille & Henry Dreyfus Postdoctoral Fellow 

BS, University of Minnesota - Duluth 1997
Coordination Chemistry with Larry C. Thompson

PhD, University of Illinois at Urbana - Champaign 2003
Bioinorganic Chemistry with Yi Lu

Research Interests: Bioinorganic chemistry, metalloprotein design
Areas of Teaching Expertise: Inorganic,  Biochemistry, General Chemistry

(218)726-7087 ; e-mail: smberry@d.umn.edu

Dr. Steven M. Berry joined the Bebout research group in June 2003 as a prestigious Camille & Henry Dreyfus Postdoctoral Fellow. Dr. Berry investigated the coordination chemistry of the zinc triad with mixed N,S-donor ligands. He prepared over ten new complexes that have been characterized crystallographically in collaboration with Raymond Butcher at Howard University. Most of these complexes have also been characterized in the solution state by multinuclear NMR. His work in the Bebout lab contributed to one published paper and two more that are in preparation. He also contributed to a an invited review article for the Structure and Bonding series.

At The College of William and Mary, Dr. Berry taught a section of Chem 151: Chemistry Laboratory I (General) in Fall 2003 and cotaught a section of Chem 420: Biochemistry Laboratory with Professor Lisa Landino in Spring 2004 and 2005. He cotaught a new section of Chem 414: Biochemistry tailored to chemistry majors with Professor Bebout during Spring 2004 and 2005. He taught a section of Chem 103: General Chemistry I.

Dr. Berry started a tenure-track faculty position in the Chemistry Department at the University of Minnesota - Duluth in fall 2005.
 

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