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An effort is made to show that it is possible to acquire high-resolution, solution NMR measurements of sol-gel (SG)-encapsulated proteins and also that extensive studies are possible with labeled proteins. The combination of SG-encapsulation and NMR spectroscopy has provided a structural data on intermediates formed by ligand photolysis and snapshots of conformation changes during ligand rebinding.

Studies reveal a new approach to deduce the presence of efficient entry and escape channels in horseradish peroxidase (HRP) with the help of diatomic probe molecules as compared to the myoglobin (Mb). The results show that slower and circuitous escape pathways are developed by this process, as Mb is supposed to be involved in the trapping of diatomic molecules and also shows that the heme relaxation dynamics are not the source of the NO rebinding to Mb.

A resonance Raman (RR) and X-ray absorption characterization of Mb-HNO, which yields new information on bonding within this species, is discussed. The results provided definitive evidence for the structure of Mb-HNO, which supports the structure deduced on the basis of NMR experiments and is the first structural characterization of an HNO bound to a heme protein.

New constituted myoglobins possessing a hydrophobic domain at the terminal of the two heme propionate side chains are constructed. The artificially created domain worked as a barrier against exogenous ligand penetration into the heme pocket, whereas the bound O2 was stabilized in the reconstituted myoglobin as well as in the native one.

A new myoglobin having a suitable amino acid configuration on the heme distal side and a hydrophobic substrate binding suite near the heme pocket at the same time is proposed. The findings indicate that the Km values significantly decrease and the Kcat/km values remarkably increase for 2-methoxyphenol oxidation catalyzed by myoglobins that are prepared by the appropriate hybridization between a mutant and a modified heme and in this approach.

The initial step of the photodissociation pathway of CO-ligated hemoglobin and myoglobin is investigated by means of time-dependent density function theory (TDDFT)(super 6) implemented in the QChem package of programs. It is observed that the iron prefers to occupy the in-plane position in the singlet states.