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The electron transfer reactions of myoglobin (Mb) are observed at an indium oxide electrode with a highly hydrophilic surface. In addition, the biological functions and the properties of Mbs reconstituted with heme and modified amino acids residues are electrochemically studied.

A proton NMR spectroscopy was used to determine the detailed structures of the alpha-cyclodextrin complexes. It is shown that a long chain surfactant molecule can bind two alpha-cyclodextrin molecules.

The chemical shifts of various compounds including cyclic and acyclic saccharides, oligoglycines, and sodium chloride using an external reference in terms of volume magnetic susceptibilities and molar volumes of these compounds is investigated. The equilibrium formation constant and structure of ion-pair of tetrathylammonium (TMA) and benzenesulfonate ion (BS) are estimated from chemical shifts referred to an internal standard.

The Myoglobin is reconstituted with the ferric complex of corrphycene in order to investigate the influence of porphyrin deformation on the equilibrium between high-spin and low-spin states in the azide derivatives. The remarkable high-spin bias of the spin equilibrium at room temperature and cleavage of the iron-histidine bond at 15 K are explained in terms of the contracted and trapezoidal metallo core that weakens the iron-histidine bond of azide metmyoglobin bearing corrphycene.

The C-HCOSY, H-H COSY, and NOESY spectra of 2-[(cyclohexylhydroxyphenylacety)oxy]-N, N-diethyl-N-methylethanaminium bromide (OB), an antiacetylcholine drug, in D(sub 2)O are studied. Calculations of molecular mechanics, molecular dynamics, and molecular hydrophobic and hydrophilic surface areas are made for the prediction of its solution structure. A pair of the corresponding protons and carbons of the cyclohexyl group are magnetically nonequivalent with one another is established.

The bitter taste of oxyphenonium bromide, an antiacetylcholine drug, is suppressed by cyclodextrins. The extent of the suppression can be predicted from the electromotive force measurements with an oxyphenonium bromide-selective electrode. The relationship between the bitter taste intensity and the electromotive force holds true, regardless of the kind and concentration of natural and modified cyclodextrins. This result is explicable on the basis of the observation that both the bitter taste and the electric potential are determined by the concentration of free oxyphenonium bromide. Some implications and limitations of the present approach are discussed.

A study was conducted to obtain the dimerization constant of propantheline bromide (PB) from the concentration dependence of the chemical shift of a PB proton. The solution structure of the PB dimer was estimated based on the Johnson-Bovey theory and molecular modeling. Docking experiments were carried out to position the PB molecule in the cavity. Results indicated anti-cooperative binding that may be correlated with the small dimerization constant of PB.

A study was conducted to analyze a technique for computing molecular surface area changes associated with the docking of host and guest. The method was utilized to estimate the structures and binding constants of cyclodextrin inclusion systems. Water-accessible molecular surface area was determined as the area of surface traced out by the center of a water molecule rolling over the van der Waals surface of the solute molecule. Results indicated the effectiveness of the method in determining the solution structures of six cyclodextrin inclusion systems.

Research was conducted to examine the aggregation patterns of sodium taurocholate (TC) and taurodeoxycholate (TDC) in an isotonic sodium chloride solution at 298.2 K using frontal derivative chromatography on Sephadex G-10 columns. Quantitative analysis was based on different aggregation models. Results indicate that the stepwise models for the self-association of TC and TDC are more rigorous than others.

A study was conducted to examine the structural and functional consequences of a 6,7-dicarboxyheme-substituted myoglobin which can be attributed to the disruption of the heme propionate-apoglobin linkage after the reconstitution. The oxygen affinities of the native myoglobin and the 6,7-dicarboxyheme-substituted myoglobin were compared. Results revealed that the heme adopted a unique orientation in the protein pocket which allowed two carboxylates to extend toward solvent sphere. The globin side chains remained intact except to those found nearby the heme 6,7-carboxylates.

A study was conducted to analyze the complex formation of diheptanoylphosphatidylcholine with alpha and gamma-cyclodextrins in deuterium oxide solutions. Proton nuclear magnetic resonance (NMR) was used to carry out the analysis. The Varian XL-300 NMR spectrometer was utilized to obtain the NMR spectra. Experimental results indicated that the magnetic nonequivalence of the terminal methyl and intermediate methylene groups induced by cyclodextrin complexation may be correlated with a decrease in mobility and difference in the environment.

The capacity factors, K', of 11 cyclic dipeptides (X-Y) including diastereomers have been determined on an RP-HPLC column in 30% and 50% methanol and 10%, 30%, and 50% acetonitrile solutions. These factors are roughly correlated with hydrophobic parameters, such as octanol-water partition coefficients estimated and k' values for alcohols. For a pair of diastereomers of cyclic (L-X-L-Phe) and (L-X-D-Phe) derivatives [k'.sub.LL] is larger than [k'.sub.LD], and for cyclic (D-Ala-L-Trp) and (L-Ala-L-Trp) [k'.sub.LL] is smaller than [k'.sub.DL], particularly in highly aqueous solutions. These elution orders can be well predicted by the holistic molecular surface area approach which takes into account the folded structures of cyclic dipeptides. The present results will be useful for prediction of the log k' values of larger peptides and the hydrophobicity and related properties of peptides.

Research has been conducted on the coordinated halide ligated iron(III) porphyrin, porphycene, and corrphycene complexes. The results of the molecular orbital calculations demonstrate the role of spin distribution on the corrphycene ring in the relationship between NMR chemical shifts and the spin state in these complexes.

Research has been conducted on the iron(III) porphyrin complexes with weak axial ligands. Results indicate that bis(tetrahydrofuran)(2,7,12,17-tetrapropylporphycenato)iron(III) perchlorate is a pure intermediate spin complex, and the results of the Mossbauer spectroscopy, (super)1 H NMR, EPR and SQUID magnetometry are presented.

The initial protein folding dynamics was investigated based on a pulsed laser light triggering method and a unique transient grating method. Plastocyanin (PC) functions as an electron transfer protein and apoPC were chemically modified with a 4,5-dimethoxy-2-nitrobenzyl (DMNB) group, which exhibits an absorpion band a 355nm, and studied the early events in the beta-sheets' refolding process of apoPC.

Laser flash photolysis method is used to study how small molecules like carbon monoxide and p-nitrophenol, which is a substrate-analogue inhibitor, affect the oxygen binding kinetics of the protein tyrosinase in Streptomyces antibioticus. The O2-binding rate constant and the initial intensity change increases with temperature and the larger intensity changes for higher temperatures may correspond to an enhancement in protein fluctuations, which increase the dissociation of the O2 molecule from the protein.

Cysteine to various sites on the surface of sperm whale human myoglobin (Mb) is introduced by mutation to investigate the effects of a cysteine residue on Mb. The rate constant for heme reduction increased for higher mutant Mb concentration, whereas it did not change significantly when the CO concentration is reduced from 100% Co to 50% Co with 50% O2.

The dimer and micelle of sodium taurocholate (TC) have the back-to-back structure as revealed by two-dimensional NMR spectroscopy. The dimer and micelles of TC in aqueous media have the back-to-back structure association (normal micelle) driven by hydrophobic interaction instead of those of face-to-face association (reverse micelle) driven by ionic interaction of hydrogen bonds.

A study was conducted, using nuclear magnetic resonance (NMR), to investigate the formation of complexes between alpha-cyclodextrin (alpha-CD) and dodecyltrimethylammonium bromide (DTAB). The result determined the accurate 1:1 and 1:2 binding constants and chemical shift variations for these complexes.

The micellar structure of sodium taurocolate (TC) in the deutrium oxide on the basis of two-dimensional NOE spectroscopy is presented. It is concluded that the concentration dependence of the chemical shift of TC is explicable in terms of dimerizatin and pentamierization.

Research has been conducted on hemiporphycene iron complex. The authors report that this complex has been incorporated into the apomyoglobin pocket in order to investigate iron atom's ligand binding ability in porphyrinoid.

The complex formation of alpha-cyclodextrin (alpha-CD) with propanesulfonate (PS) and propanol (PrOH) is investigated by proton NMR spectroscopy and molecular surface area calculations. The solution structures of the 1:1 complexes of alpha-CD with PS and PrOH are estimated on the basis of vicinal coupling constants and two-dimensional phase-sensitive nuclear Overhauser effect spectroscopy (ROESY).

The proton NMR and molecular surface area calculations are used to investigate the complex formation of benzenesulfonate (BS) and alpha-cyclodextrin (alpha-CD). In addition, the crystal structure of the complex of sodium benzenesulfonate (BS) and alpha-CD are determined using the Johnson-Bovey theory and the ROESY spectrum.

The aggregation patterns of sodium taurochenodeoxycholate and tauroursodeoxycholate (TUDC) in an isotonic sodium chloride solution are investigated. The result suggests that 7beta-hydroxyl group of TUDC inhibits micellar growth because of increased intermolecular mismatching contact with the hydrophobic surface and decreased intermolecular hydrogen bonds in the micelle.