Photo of Kassner, Richard

Richard Kassner

Emeritus Professor

Address:

4236 SES, MC 111

Office Phone Voice:

(312) 996-5202

About

I am interested in the role of transition metal ions in biological systems. Transition metal ions are usually found coordinated to the side-chains of amino acid residues in proteins or in specialized coordination complexes such as heme which are bound to proteins. The metal ion represents the active site of many proteins participating in such diverse functions as electron transfer, catalysis and O2 transport and storage. It is remarkable that each of these functions is associated with different heme proteins. The particular function and properties of the heme group are determined by the protein to which it is attached.

My research group is studying the manner in which the structure of the protein alters the redox potential, spin state, ligand binding and catalytic properties of the heme iron to suit it for a particular function. We are attempting to identify the structural parameters in proteins through a comparative study of heme proteins and model heme complexes as well as using the techniques of molecular biology to carry out site-directed mutagenesis of particular amino acids in a heme protein. The studies involve a variety of chemical and spectroscopic methods including UV/VIS, IR, Raman and NMR. Such studies will help to reveal the structural basis for differences between normal and abnormal mutant hemoproteins.

 

The structure of a protein elucidated by the Kassner lab.
C. vinosum cytochrome c' is a dimeric hemoprotein with a four a-helical bundle structure. The protein environment surrounding the vacant axial ligand site of the heme iron is being studied to understand the ligand binding properties of the protein.

Education

BS, Purdue University, 1961
PhD, Yale University, 1966
Postdoctorate Fellow, University of California, San Diego, 1966-68
Visiting Scholar, Stanford University, 1976