Chemistry Faculty

Protein structure is directly related to protein function, and the amino acid sequence that represents a particular gene contains all the necessary information to achieve that structure.  I am interested in how protein structures evolve, with particular emphasis on utilization of the iron-protoporphyrin cofactors such as heme from hemoglobin and myoglobin.  My studies of heme-proteins can be divided into two major projects.

1.  Biophysical characterization of a heme-peptide construct from cytochrome c: 
  
This projects involves the examination of the factors that modulate reduction potential in cytochrome c, and important protein in the electron transport chain.  Cytochrome c is characterized by a c-type heme, where the heme is covalently attached to the protein through two vinyl groups and two conserved cysteine residues in a CXXCH motif.  The XX in the motif represents that nearly any combination of amino acids have been found in different genes.  In particular, this protect is concerned with the role of the variable XX residues in promoting heme distortion through steric strain on the covalently attached cysteines.  The project will involve studying a heme-peptide construct that represents the CXXCH attachment motif.  Site directed mutagenesis will be used to examine the effect of residue size in the XX region.  Subsequent biophysical characterization will be done with NMR, cyclic voltammetry, and UV-Vis spectroscopy to look at heme electronic structure and reduction potential.

2.  A phylogenetic and structural analysis 2/2 hemoglobins: