Magnetic spectroscopic (EPR, ESEEM, Mössbauer, MCD and NMR) studies of low-spin ferriheme centers and their corresponding heme proteins

Synthetic model compounds for hemoproteins

The Chemistry and Biochemistry of Heme c: Functional Bases for Covalent Attachment

Still a puzzle: why is haem covalently attached in c-type cytochromes?

https://www.jbc.org/content/260/29/15699.full.pdf

Myoglobin: cytochrome b5 interactions and the kinetic mechanism of metmyoglobin reductase.

A proton NMR method is described for determining the orientation of a porphyrin within the heme pocket of a hemoprotein. The pattern of the hyperfine-shifted heme methyl resonances in low-spin ferric model compounds is demonstrated to characteristically reflect the position of a localized low-symmetry perturbation on the pi system. The specific assignments via deuteration of the two interconvertible sets of methyl resonances observed for deuteroporphyrin-reconstituted sperm whale metmyoglobin cyanide lead to the conclusion that the low-symmetry perturbations on the heme due to the apo-protein contacts differ for the two protein components by a 180 degrees rotation about the alpha-gamma meso axis. Hence the heme in the reconstituted myoglobin is "disordered" in solution, and the altered functional properties of the reconstituted protein cannot be simply attributed to the local effect of the heme substituent. This NMR technique has applicability for determining the relative heme orientation in related hemoproteins, and may clarify the origin of doubling of heme resonances observed in several native hemoproteins.

https://www.pnas.org/content/pnas/75/12/5755.full.pdf

Proton nuclear magnetic resonance characterization of heme disorder in hemoproteins.

NMR studies of low-spin ferric complexes of natural porphyrin derivatives. 1. Effect of peripheral substituents on the .pi. electronic asymmetry in biscyano complexes

Letter: Nuclear magnetic resonance study of stereospecific dimerization of dicyanohemin.

Regioselective base-catalyzed exchange of ring methyl protons in protoporphyrin IX. A new facet of porphyrin chemistry.

NMR studies of low-spin ferric complexes of natural porphyrin derivatives. 2. Determination of the dimer structure of the biscyano complex using intermolecular paramagnetic dipolar relaxations

David B. Viscio

Papers

Proton nuclear magnetic resonance characterization of heme disorder in hemoproteins.

NMR studies of low-spin ferric complexes of natural porphyrin derivatives. 1. Effect of peripheral substituents on the .pi. electronic asymmetry in biscyano complexes

Letter: Nuclear magnetic resonance study of stereospecific dimerization of dicyanohemin.

Regioselective base-catalyzed exchange of ring methyl protons in protoporphyrin IX. A new facet of porphyrin chemistry.

NMR studies of low-spin ferric complexes of natural porphyrin derivatives. 2. Determination of the dimer structure of the biscyano complex using intermolecular paramagnetic dipolar relaxations