Ken Rousslang

Department of Chemistry

Office: Thompson 390K
Phone: 253-879-3124
rousslang@ups.edu
(and a little more about me or my publications) at my Blackboard web site

RESEARCH INTERESTS

The Relationship Between Structure and Function In Proteins

The precise physiological function of the molecules that make up our bodies is highly dependent upon their three-dimensional shape. Many of the active molecules in our bodies are proteins, such as enzymes or hormones. For example, the way in which an enzyme performs its specific function depends intimately upon its structure-whether it snips a chemical bond, or binds another molecule. The action of a hormone requires a shape and size compatible with its receptor.

Under controlled conditions in our laboratory, when these molecules are irradiated with a laser or high intensity arc lamp or other light source, they absorb light at a characteristic wavelength, and then emit light at a new wavelength. Absorption and subsequent emission of visible light by these molecules provides a means for inferring the structure of these submicroscopic systems that govern important body functions. For example, we have used the interaction of light with matter to gather information about molecular systems involving liver function, reproduction, and blood sugar regulation.

We examine the steady-state and time-dependent light emission from aromatic amino acids such as tryptophan in proteins. We measure the induced fluorescence and phosphorescence of each protein systematically and compare it to the results from better understood systems. The work involves the use of computer-controlled instrumentation that was built and developed by me and the students who have worked with me in the lab, providing a range of opportunities for research that emphasizes one or more of the areas of instrument automation, computer programming, mathematical modeling and statistics, quantum mechanics, physical biochemistry, or the use of lasers in applications in luminescence.

Current projects include the study of tissue factor protein (TFP), essential in the process of blood clotting, and the study of a single tryptophan containing protein involved in phosphorylation. Molecular samples are provided by colleagues at the University of Washington Departments of Obstetrics and Gynecology, and Biochemistry, and by the Mt. Sinai Medical Hospital.

From the phosphorescence emission spectrum and excited state decay of the four tryptophan residues in human tissue factor protein, we hope to gain information about the three dimensional solution conformation of the protein. This information will help to elucidate the physiological role of TFP in the process of clotting in the human body, and help answer the more general question of the relationship between protein structure and function. The proteins involved in the mechanism of oxidative phosphorylation are of fundamental interest.

References

Ross, J. B. A., Rousslang, K. W., DeHaen, C., Lavis, V. R., and Deranleau, D. A.; [12-homoarginine]glucagon: Synthesis and Observations on Conformation, Biological Activity, and Copper-mediated Peptide Cleavage, Biochem. Biophys. Acta 576, 372-384 (1979).

Ross, J. B. A., Rousslang, K. W., and Brand, L.; Time-Resolved Fluorescence and Anisotropic Decay of Tryptophan in Adrenocorticotropin (1-24). Biochemistry 20, 4361-4369 (1981).

Petra, P. H., Namkung, P. C., Senear, D. F. McRae, D. A., Rousslang, K. W., Harding, C. O., Teller,D. C., and Ross, J. B. A.; Molecular Characterization of the Sex-Steroid-Binding Protein (SBP) of Plasma. Re-Examination of Rabbit SBP and Comparison with the Human, Macague, and Baboon Proteins. J. Steroid Biochem. 25, 2, 191-200 (1986).

Rousslang, K. W., Allen, L. and Ross, J. B. A.; Phosphorescence Maxima and Triplet State Lifetimes of NAD+ and e-NAD+ in Ternary Complexes with Horse Liver Alcohol Dehydrogenase. Photochem. Photobiol., 49, 2, 137-143 (1989).

Recent Publications

Esposito, A. P., Rousslang, K., and Reid, P. J., Direct Evidence for the Ultrafast Photoisomerization of Chlorine Monoxide in Condensed Environments, Journal of Photochemistry and Photobiology A, Chemistry 129 (1-2), pp. 9-15, 2000.

Ross J. B. A., Rusinova, E., Luck, L. A., and Rousslang, K. W., Spectral Enhancement of Proteins by in vivo Incorporation of Tryptophan analogues, chapter in Topics in Fluorescence Spectroscopy, Volume VI: Protein Fluorescence (Lakowicz, J. R., ed.), 2000.

Rousslang, K. W., Reid, P. J., Haynes, D . R., Holloway, D. M., Dragavon, J., and Ross, J.B. A., Time-Resolved Phosphorescence Of Tyrosine, Tyrosine Analogs, And Tyrosyl Residues In Oxytocin And Small Peptides, J. Protein Chemistry, 21: 547-555, November 2003 .

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ROUSSLANG (rousslang@ups.edu)