Professor Department of Biochemistry, University of Kentucky (7/95-present) Joint appointment Graduate Center for Toxicology, University of Kentucky (7/96-present) Joint appointment Department of Chemistry, University of Kentucky (9/97-present) Director Biological NMR Facility, University of Kentucky (7/95-present)

Research Interests  |  Publications  |  PubMed

Research Interests

      The central theme of our research is understanding and describing the specific interactions and structural parameters that govern recognition between molecules.

      Nucleic Acids: Our main research effort is focused on understanding the dynamics and conformational differences between damaged and undamaged DNAs, and their interactions with repair proteins. The primary tools that are employed in these studies are nuclear magnetic resonance spectroscopy (NMR) and synthetic organic chemistry. We have observed evidence for altered helix dynamics in response to photo-alkylation of DNA by the mutagen psoralen. The results of these studies should help clarify the relationship between DNA damage, DNA repair and carcinogenesis. We are continuing to develop techniques to incorporate dynamic information from NMR into the structure determination of nucleic acid solution conformations. Data of this kind will enable the community to deduce DNA structures more accurately from spectroscopic data, and to understand the limitations of those structures better. Many protein components of DNA repair systems in both prokaryotes and eukaryotes have been identified and are ripe for biophysical investigation.

      My group also focuses on understanding the molecular interactions that govern molecular recognition of ligand-nucleic acid and ligand-protein systems. Synthetic, enzymatic and NMR studies of ligand-macromolecule complexes yield structural information that allows identification of some of the intermolecular features that are involved in specific molecular recognition processes. DNA and RNA are logical targets for the rational structure based development of therapeutic agents because of their central role in metabolism. Small molecule ligand-DNA systems can be synthesized with reasonable ease and are spectroscopically tractable. The many different kinds of binding modes exhibited by molecules with DNA makes it possible to decompose the interactions into various simpler components.

      Isoprenylation: The superfamily of GTP-binding proteins are involved in the regulation of cellular receptor mediated signaling pathways. These small G-proteins are regulated by both post-translational modifications and interactions with a number of regulatory proteins. Post-translational modification by isoprenylation involves the covalent attachment of either a 15-carbon farnesyl or 20-carbon geranylgeranyl group to COOH-terminal cysteines and is crucial for the biological activity of these proteins. The post-translational isoprenylation of proteins requires multiple steps of substrate recognition. We are working with Professor Doug Andres' group to synthesize and evaluate new heterobifunctional photo-affinity probes to study the biochemistry of protein isoprenylation in eukaryotic cells.

      Fullerenes: Working with Professor Mark Meier's group, we are developing methodology for the selective functionalization of fullerenes. In particular, we are interested in the functionalization of fullerene derivatives through chemical modification of hydrogenated fullerenes. The central focus of our efforts is understanding of how the initial addition reaction directs the reactivity of the remaining C=C bonds in the molecule. The application of NMR methods has been critical for obtaining definitive structural proof of these new materials.

      PCB's: In Conjuction with Professor Larry Robertson's group, we are investigationg the chemistry of metabolically activated polychlorinatedbiphenys (PCB). We are particularly interested in the potential formation of DNA adducts by these compounds.

Selected publications

Research problems for undergraduate (BCH/CHE 395) and graduate students.

1. Structure and dynamics of nucleic acids.
2. Synthesis of novel heterobifunctional photoprobes.
3. The mechanism of action of protein isoprenylation.
4. The chemistry and structure of fullerenes (C60, C61, C70 C84 etc.).
5. NMR spectroscopy in structural biology.

DNA Structure & Function:

Micali, E., Chehade, K. A. H., Isaacs, R. J., Andres, D. A. and Spielmann, H. P. (2001) "Protein Farnesyltransferase Isoprenoid Substrate Discrimination is Dependent on Isoprene Double Bonds and Branched Methyl Groups" in press, Biochemistry.  Abstract

Isaacs, R. J. and Spielmann, H. P. (2001) "NMR Evidence for Mechanical Coupling of Phosphate BI-BII Transitions With Deoxyribose Conformational Exchange in DNA" J. Mol. Biol. 311, 149-160. Abstract

Isaacs, R. J. and Spielmann, H. P. (2001) "Relationship of DNA Structure to Internal Dynamics: Correlation of Helical Parameters from NOE Based NMR Solution Structures of d(GCGTACGC)2 and d(CGCTAGCG)2 with 13C Order Parameters Implies Conformational Coupling in Dinucleotide Units" J. Mol. Biol. 307, 525-540. Abstract

Skrzypek, M., Lester, R. L., Spielmann, H. P. Zingg, N., Shelling, J. and Dickson, R. C. (2000) "Dominant suppressor mutation bypasses the sphingolipid requirement for growth of Saccharomyces cells at low pH: role of the CWP2 gene" Curr. Genet 38, 191-201. Abstract

Spielmann, H. P. (1998) "Dynamics of a Bis-intercalator DNA Complex by 1H-Detected Natural Abundance 13C NMR Spectroscopy" Biochemistry, 37 (48), 16863-16876 Abstract

Spielmann, H. P. (1998) "Dynamics in Psoralen Damaged DNA by 1H Detected Natural Abundance 13C NMR Spectroscopy" Biochemistry 37, 5426 -5438. Abstract

Yang, D., Strode, J. T., Spielmann, H. P., Wang, A.H.-J. and Burke, T. G. (1998) "DNA Interactions of Two Clinical Camptothecin Drugs Stabilize Their Active Lactone Forms" J. Am. Chem. Soc. 120, 2979-2980. Abstract

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Protein Isoprenylation

C. Than, H. Morimoto, P.G. Williams, K. A. H. Chehade, D. A. Andres and H. P. Spielmann (2001) "Preparation, NMR Characterization and Labeling Reactions of Tritiated Triacetoxy Sodium Borohydride" J. Org. Chem. 66, 3602-3605. Abstract

Chehade, K. A. H. and Spielmann, H. P. (2000) "Facile and Efficient Synthesis of 4-Azidotetrafluoroaniline: A New Photoaffinity Reagent" 65, 4949-4953. J. Org. Chem. Abstract

Kareem A. H. Chehade,  Douglas A. Andres,  Hiromi Morimoto and  H. Peter Spielmann  (2000) "Design and Synthesis of a Transferable Farnesyl Pyrophosphate
Analog to Ras by Protein Farnesyltransferase" J. Org. Chem. 65, 3027-3033. Abstract

Fullerene Chemistry

H. Peter Spielmann, Brad R. Weedon, and Mark S. Meier (2000) "Preparation and NMR Characterization of C­₇₀H₁₀:  Cutting a Fullerene p-System in Half"   J. Org. Chem, 65, 2755-2758.  Abstract

Weedon, B. R., Haddon, R. C., Spielmann, H. P., and Meier, M. S. (1999) "Fulleroid Addition Regiochemistry is Driven by p-Orbital Misalignment" J. Am. Chem. Soc., 121, 335 -340. Abstract

Spielmann, H. P., Wang, G-W., Meier, M. S, and Weedon, B. R. (1998) "Preparation of C70H2, C70H4 and C70H8: Three Independent Reduction Manifolds in the Zn(Cu) Reduction of C70" J. Org. Chem, 63, 9865-9871. Abstract

Spielmann, H. P., Wang, G-W., Meier, M. S, and Weedon, B. R. (1998) "Preparation of C70H2, C70H4 and C70H8: Three Independent Reduction Manifolds in the Zn(Cu) Reduction of C70" J. Org. Chem, 63, 9865-9871.

Weedon, B. R., Meier, M. S, and Spielmann, H. P. (1998) "Hydrogenation of the Parent Fulleroid of C60 by Zinc/Copper Reduction" Recent Advances in the Chemistry and Physics of Fullerenes and Related Materials, 6, In Press.

Bergosh, R. G.; Meier, M. S.; Spielmann, H. P.; Wang, G.-W.; Weedon, B. R. (1997) "The Lower Hydrides of C60 and C70," In Recent Advances in the Chemistry and Physics of Fullerenes and Related Materials, 4, 240-245.

Bergosh, R. G., Meier, M. S., Laske Cooke, J. A., Spielmann, H. P. and Weedon, B. R. (1997) "Dissolving Metal Reductions of Fullerenes" J. Org. Chem. 62, 7667-7672. Abstract

Meier, M. S, Weedon, B. R., Spielmann, H. P. (1996) "Synthesis and Isolation of One Isomer of C60H6" J. Am. Chem. Soc. 118, 11682-11683. Abstract

Metabolism of PCBs

Amaro, A. R., Oakley, G. G., Bauer, U., Spielmann, H. P., Robertson, L. W. (1996) "Metabolic activation of PCBs to Quinones: Reactivity toward Nitrogen and Sulfur Nucleophiles and Influence of Superoxide Dismutase" Chemical Research in Toxicology 9, 623-629. Abstract