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A molecular dynamics study is conducted to analyze the correlations between the nuclear volume, solvent-accessible surface and the folding state of various unfolded conformers of a [alpha] or a [beta] protein with any helical peptide. The results prove that the unfolded conformations need not be necessarily extended, as the volume variation does not affect the folding state to a large extent and hence is ignored in the study of the interiors of the protein.

The synthesis of three types of met- and zinc- myoglobin dyads, ZnMbAc(4)[Me.sup.+], ZnMbAc(6)[Me.sup.+], and metMbAc(6) is described by incorporating chemically modified metalloporphyrin cofactor appending an acridine(Ac) or a methylacridium ion ([[AcMe].sup.+]) into apo-Mb. It is shown that synthetic manipulation at the Mb surface with the use of an artificial DNA binder along with photoinduced reaction, can give insight to build new Mb-DNA complex and sensitive fluorescent for DNA.

A study shows that classical electrostatistics describes the quantitative description of, both the binding of the diatomic ligands XO (X= C. N, O) to the heme group in myoglobin and the dependence of their vibrational frequencies upon an external field by classical electrolysis. It is suggested that ligand binding occurs via an electrostatic bond, a generalization of the standard ionic bond to include induction, and that classical electrostatics can replace quantum mechanics for a considerable simplification of some complex problems.

A method for diffusion coefficient (D) measurement for proteins based on the pulsed laser-induced transient grating method using a photosensitive cross-linker is applied to characterize the pH denaturation process of holo- and apo-myoglobin (Mb) from the viewpoint of protein-water interaction. It is found that the pH denaturation curve monitored by D agrees quite well with that determined by the circular dichroism intensity for holo-Mb.

A demonstration of two-dimensional heterocorrelation analysis between spectrally resolved and temporally resolved fluorescene is presented to investigate the decay dynamics of the 8-anilino-1-naphthalenesulfonate-(ANS-) apomyoglobin complex. The relative decay dynamics across the emission spectra are resolved without measuring fluorescence lifetime at each wavelength as in the approach of decay-associated spectra.

Covalently linked films of the ferric heme protein myoglobin and poly-L-lysine graphite electrodes reacted with tert-butylhydroperoxide (tBuOOH) to form ferryloxy protein species according to Michaelis-Menten enzyme kinetics. Apparent kinetic constants are most likely governed by acidity-controlled protein conformations and their binding with tBuOOH in the intermediate protein-substrate complex.

The photolysis and rebinding kinetics of carboxy-myoglobin (MbCO) embedded in a trehalose glass at room temperature using transient absorption and diffractive optics-based phase grating spectroscopy on nanosecond to microsecond time scale was investigated. The result suggests that protein structure plays a significant role in the bond energies at active sites which in turn provides a tuning element of the effective barrier heights independent to the transition state region.

CO rebinding kinetics after nanosecond photolysis of myoglobin encapsulated in wet silica gels exhibits an enhanced geminate phase that allows the determination of the microscopic rate constants and the activation barriers for distinct ligand docking sites inside the protein matrix. The germinate phase can be well-described by a biphasic lifetime distribution, using a maximum entropy method, reflecting rebinding from the distal and proximal sites.

The rebinding of CO to myoglobin (Mb) from locations around the active site is studied using a combination of molecular dynamics and stochastic simulations for native and L29F mutant Mb. It is observed that in the case of L29F mutant, the free-energy surface is flatter and the dynamics is much more rapid.

Ultrafast protein dynamics of the CO adduct of a myoglobin mutant with the polar distal histidine replaced by a nonpolar valine (H64V) are investigated by spectrally resolved infrared stimulated vibrational echo experiments and molecular dynamics (MD) simulations. It is observed that in aqueous solution at room temperature, the vibrational dephasing rate of CO in the mutant is reduced by approximately fifty percent relative to the native protein.

The dynamics of nitric oxide (NO) rebinding to Mb and its model system, microperoxidase, in D2O solution at 283 K after photolysis was directly observed by monitoring the stretching mode of NO using time-resolved IR spectroscopy is accurately determined. The transient spectra of photolyzed MbNO reveal two overlapping vibrational bands for bounds NO 1598 and 1611 cm(super -1).

9-287 GHz electron paramagnetic resonance (EPR) spectroscopy is used to examine the location of peroxyl radical in horse heart myoglobin (Mb), oxidized with H2O2. The high-field EPR spectra of the Mb peroxyl radical are simulated using a Hamiltonian, which describes the exchange and dipolar interaction between an oxoferryl iron and a protein radical.

The resonant Raman active mode identified in numerous studies as the heme iron-histidine stretch in the Raman spectrum of 15 exogenous ligands to the heme iron in the myoglobin proximal cavity mutant H93g is investigated. It is seen that Raman bands attributed to in-plane modes of the heme are unaffected by the change in heme-iron ligation.

Two oppositely charged polysaccharides, quaternized hydroxyethyl cellulose ethoxylate (HECE) and alginate (AA), are assembled into [{HECE/AA}.sub.n] layer-by-layer (LBL) films and the films are used to load myoglobin (Mb) from its solution. This model has provided an effective approach to control the electroactivity of immobilized redox proteins in the multilayer assembly containing weak polyions by adjusting pH and has developed controllable electrochemical biosensors based on the direct electrochemistry of enzymes.

The refolding mechanism of apomyoglobin (apoMb) subsequent to high-temperature unfolding is examined by computer simulations. The results have shown that apoMb has followed a different folding pathway after high-temperature denaturation.

The diffusion of carbon monoxide through myoglobin is explored by calculating molecular dynamics trajectories. The classical equations of motion are integrated for 2 nanoseconds and the resulting pathways are analyzed.

Environmental perturbation leading to changes in protein hydration and local motion in apomyoglobin are explored to describe the mechanism of cold denaturation. Low temperature produces solvent-induced packing defects at the protein surface.

The comparative analysis of two structurally related phenothiazine drugs, promazine and triflupromazine hydrochlorides are presented. The studies provide insight into drug-protein affinity and thermodynamic denaturation parameters.

Tetrahertz (THz) time-domain spectroscopy is applied to measure the absorption of electromagnetic radiation from 0.1 to 1.2 THz for Mb-water mixtures. The results demonstrate that THz absorption per protein molecule is increased by presence of biological water and that water increases the protein polarizability.

The terahertz time-domain spectroscopy (THz-TDS) investigations of myoglobin (Mb) powder, at several hydration levels between 3.6 and 4.2 wt %, are presented. The result suggests that the absorption mechanisms are similar to those in liquid water, and hinders the spectroscopic identification of biomolecules in frequency range.

A computational study of the heme relaxation process in two tailored myoglobins-the His93Gly mutant with native heme b (b is in italic) and wild type myoglobins in which the two isopropionate side chains in the heme were each replaced by hydrogen atoms is presented. The simulation results suggest that little change in the relaxation rate is expected for the His93Gly mutant with native heme b (b is in italic) - and its acidic chains are intact.