Jack Throck Watson
Emeritus Professor, Biochemistry
Emeritus Professor, Chemistry
- B.S., 1961, Iowa State University
- Ph.D., 1965, M.I.T.
- 1965-68, USAF School of Aerospace Medicine
- Postdoctoral Researcher, 1968-69; Institut de Chimie, Strasbourg, France
- 1969-1980, Faculty Member, Vanderbilt University
- 1988, 1995. Professeure Invité Ecole Normale Superieure, Paris. Analytical Chemistry
watsonj@msu.edu
501A Biochemistry Building
Michigan State University
East Lansing, MI 48824-1319
Office: 517-353-0855
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Jack Throck Watson Research Interests continued
Secondary Structure (continued)
We have developed a chemical approach to disulfide bond mapping that involves chemical cleavage on the N-terminal side of cyanylated cysteines to yield degradation products that can be analyzed by D/I for mass mapping of the peptide or protein. By combining this cyanylation approach with the technique of partial reduction of proteins containing more than one disulfide bond, we have demonstrated that it is possible to deduce the connectivity of cysteines involved in a given disulfide bond. Furthermore, we can cyanylate at low pH to avoid disulfide bond exchange. Our cyanylation/mass mapping approach also is applicable to peptides and proteins involving adjacent cysteines in their primary structure. This novel mass mapping approach to disulfide bond analysis offers new hope to protein chemists studying tightly knotted proteins that are refractory to conventional methodology. Representative projects include characterizing the disulfide bonding structure of proteins involved in von Willebrand disease (bleeding disorder), the putative misfolded proteins involved in cataract formation, vasoendothelial growth factor which controls growth of new blood vessels in cardiovascular beds and in tumor formation, and in natural products containing small, but tightly knotted peptides that inhibit HIV proteases.
Protein Folding (continued)
Proteins containing cystines that are involved in disulfide bond formation during the refolding process have been widely studied, but there is controversy concerning the trapping of folding intermediates because of problems with disulfide bond exchange, etc. We have demonstrated in studies with human epidermal growth factor that our cyanylation methodology is applicable to the trapping of sulfhydryl-containing intermediates involved in the refolding of cysteine-containing proteins.
Our cyanylation methodology offers the advantages of trapping the folding intermediates in an acidic medium to avoid disulfide bond exchange. Cyanylation of the free sulfhydryls quenches any further folding of the intermediates, and initiates the analytical protocol for direct determination of the disulfide bonding pattern. We are presently studying the refolding of long R3 insulin-like growth factor.
Full text of research interests