## Doctoral Dissertations

Fall 1997

Dissertation

Chemistry

#### Degree Name

Doctor of Philosophy

An iron nitrosyl complex of transferrin was studied. Three methods of generating nitric oxide gas were tested and resulted in no differences in product formation. The g-factors for the rhombic complex--prepared with and without carbonate addition to the buffer--were determined. For the complex prepared with carbonate g$\sb{\rm x}$ = 2.052, g$\sb{\rm y}$ = 2.028, and g$\sb{\rm z}$ = 2.013. For the complex prepared without addition of carbonate g$\sb{\rm x}$ = 2.051, g$\sb{\rm y}$ = 2.028, and g$\sb{\rm z}$ = 2.011. Complex concentration was little affected by the addition of extra Fe$\sp{2+},$ but does decrease over time after reaching a maximum two to three minutes after the start of the reaction. The complex was observed to form preferentially at the C-terminal lobe of the protein. The histidine residue, which normally serves as a ligand for Fe$\sp{+3}$ does not appear to be necessary for binding of the iron nitrosyl complex. An ENDOR spectrum of the complex obtained at 3.6 K yielded a signal attributed to the effect of matrix protons.