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Research has been conducted on the porphyrin arrays, a hexamer and a nonamer. The synthesis and characterization of these arrays have been carried out via elemental analysis and spectroscopic methods, and the results indicate that the construction scheme of these arrays involves sequential organic and inorganic reactions performed at the central tin(IV) ion of the porphyrin scaffold and at the peripheral meso-phenyl ring.

Research has been conducted on the solvated copper(I) and silver(I) perchlorate salts which crystallize from the N,N-dimethylthioformamide solution. The crystal structures of these salts have been determined via the single-crystal X-ray diffraction and the details are reported.

Research has been conducted on the methyl phosphite and methylethyl phosphate. Results indicate that these compounds may be used as probes of the paramagnetic metal ion reactivities toward the inner shell coordination exchange without the studies of the variable temperatures.

Research has been conducted on the alkali metal ions Li (super)+, Na (super)+ and K (super)+ in the constrained inositol orthoformate derivatives. The structural features conductive to the complexation of these metal ions have been investigated in solution, in the solid state and in the gas phase via the electrospray ionization mass spectroscopy and the details are discussed.

Research has been conducted on the type II restriction endonuclease BamHI which catalyzes the photodiester bond scission in the GAGTCC cognate sequence in the divalent metal ion presence. The role of the metal ions in the BamHI first step catalysis has been investigated and the findings indicate that the nucleophilic water molecule deprotonation by a substrate-assisted mechanism is unlikely.

Research has been conducted on the properties of the transition-metal complexes with coordinated radicals. The design and synthesis of the molecular-based magnetic materials have been explored via the metal-radical assemblies and the results are discussed.

Research has been conducted on the dimethyl sulfoxide solvated thallium(III) ion. The vibrational spectra and the structure of this ion have been investigated in the dimethyl sulfoxide solution and in a solid state, and the results of the comparison of the coordination and bonding of solvated thallium(III) ions with those of the other solvated metal ions with the d (super)10 electronic configuration are presented.

Research has been conducted on the alpha-alanine and the stable adducts if forms with lithium, sodium and potassium cations. The study of the conformations of these alanine and adducts has been performed via the density functional theory and the results are discussed.

Pyrococcus horikoshii 999 pyrazinamidase exhibits 37% homology to that of Mycobacterium tuberculosis and possesses a zinc-binding site in the active site of the enzyme. Crystal analysis indicates that enzyme inhibition at the metal ion-binding site results in the loss of enzyme activity, which leads to pyrazinamide-resistance in M. tuberculosis.

Research reveals that hammerhead ribozyme cleaves RNA between nucleotides G8 and A9 and the cleavage is mediated by metal ions. Data indicate that zinc is a preferred metal ion although nickel, cobalt, manganese, cadmium, and lead can also catalyze the cleavage. Alkaline-earth metals barely cleaved the ribozyme.

Research has been conducted on the metal ions promoting RNA catalysis. The roles of the metal ions involved in the glutamine-recognition domain distinct from those involved in the aminoacyl-transferase ribozyme domain have been investigated and the results are reported.

Research has been conducted on the catalytic residues of the ribozyme. The spatial arrangement of these ribozymes in the relation to the metal binding site has been investigated and the results are reported.

Research reveals that zinc causes an expansion of the footprint protection instead of abolishing the trans-acting regulator, SmtB-operator/promoter complex. Further, zinc does not affect the C3 protein-DNA complex.

Research has been conducted on the pyrazolyl ligands. The preparation of these ligands and their interactions with the Pd(II) salts have been investigated and the results indicate that the interactions with metal ion accelerate the P-N bond hydrolysis.

Research has been conducted on the phosphorus pyrazolides hydrolytically sensitive to the transition metal ions. The study of the tethered pyrazolyl phosphinate with the pyrazolyl group separated from the phosphorus via the pyrazolyl nitrogen atom is reported.

Research has been conducted on the tetradentate enediyne macrocycles. The syntheses of these macrocycles with the 24-, 26- and 28-membered rings has been carried out and the results of their thermal reactivities and those of Cu(II), Cu- and Zn(II) complexes are described.

Research demonstrates the kinetic allosteric properties of the divalent metal magnesium-activated yeast pyruvate kinase and metal modulation of the ligand interactions with the enzyme. Data suggest a regulatory role for the divalent metals in the glycolytic pathway.

The differential behavior of superoxide dismutase proteins, containing iron and manganese as metal ions, is due to differences in the hydrogen bonding between proteins and a solvent molecule coordinated to the metal ion. The reduction potential (E(sub)m) of the metal ions is influenced by the proton uptake by the enzyme upon reduction.

Research has been conducted on the mixed-valent uranium(V/VI) oxo-imido complex. The synthesis and structural characterization of this complex have been carried out and the results are reported.

Research has been conducted on the monoazathiacrown ethers. The synthesis of these ethers has been carried out and their metal-ion properties have been examined via the solvent extraction for the purpose of applying them in the supramolecular systems as building blocks.

Research has been conducted on the dipeptidyl peptidase III. The zinc ions in this peptidase have been replaced with Co (super)2+ and Cu (super)2+ in determining the involvement of the metal ions in the enzyme activity expression and in characterizing the metal ion geometry.

Research has been conducted on the bacteriorhodopsin. The temperature dependence of the bacteriorhodopsin's FT-IR spectra as a function of pH has been examined and the results indicate a strong dependence of the irreversible melting transition on the pH of the native bacteriorhodopsin.

Research has been conducted on the soluble chaperone calreticulin. The structural properties of the human calreticulin affected by the calcium and zinc ions have been investigated via analytical ultracentrifugation, proteolysis and circular dichroism and the results are discussed.

Results reveal that steady-state kinetic and thermodynamic studies of an N-terminally truncated and full-length type 2 human methionine aminopeptidase exhibit identical kinetic and physical properties. Data indicate that full-length enzyme is activated by cobalt(II) cation.

Research shows that sub-femtomolar range of zinc(II) is enough to cause half-maximal rate of the transcriptional activity in Zur protein of Escherichia coli. Data indicate that Zur possesses two distinct metal binding sites and the coordination between the two binding sites leads to an exceptional zinc sensitivity.

Research has been conducted on the tripodal ligand used in the synthesis of different monomeric complexes with the terminal hydroxo ligands. The isolation and characterization of these complexes have been carried out and the results are reported.

Research has been conducted on the OXA-10 and 14 class D beta-lactamases. The factors affecting the oligomerization state of these lactamases in solution have been investigated and the results indicate that these enzymes exist as an equilibrium mixture of a monomer and a dimer.

Research has been conducted on the stereoselectivity of the DNA polymerase. The pre-steady-state kinetic analysis of this stereoselectivity and its alteration by metal ions and by site-directed mutagenesis are discussed.

Research has been conducted on the trivalent lanthanide complexes of macrocyclic polyaminopolycarboxylate ligands TETA and DOTA. The kinetic, thermodynamic and structural properties of these ligands and the the ligand preorganization effect on the metal ion complexation have been investigated.

Insights into the critical role of manganese homeostasis are discussed relative to bacteria in this review article. New experimental and genomic sequence data indicate that some microorganisms, among them the Lyme disease pathogen, Borrelia burgdorferi, may not require iron, needing manganese instead for the metabolic and survival strategies they have evolved. Where competition for available iron exists, ability to get along without it can be a selective advantage, although a cell is capable of very few reactions, and no aerobic respiration.

Research has been conducted on the bleomycin and metallobleomycins. The interaction properties of these agents with site-specific and nonspecific DNA oligomers have been investigated.

Results reveal that although structural similarities are seen between acyl-transferase ribozymes, HS01 and E18, their dependency on the metal species for catalysis differs. The catalytic activity of ribozyme HS01 requires the inner-sphere coordinated magnesium ion whereas ribozyme E18 requires a fully hydrated outer-sphere magnesium ion.

A Staphylococcus aureus Zn(super.2+)-responsive regulatory element is discussed. The putative operon, zur, and components of an ABC-type transporter have been characterized, and it appears zur has no role in pathogenicity in a lesion model of S. aureus infection..

Research has been conducted on the enantiomerically pure spirocyclic alpha,beta-butenolides. The synthesis of these butenolides carried out via the acid- or bromonium ion-induced rearrangement of carbinol is described.

Research has been conducted on the nitrogenous entity-separated ion pairs. The generation of these ion pairs which contain nitrogen gas, benzyl cations and pivalate anions has been carried out via N-benzyl-N-nitrosopivalamide thermal deamination and the details are reported.

Research has been conducted on the spirobenzopyran derivatives. The synthesis of these derivatives carrying the oxomethylcrown ether moiety has been carried out and the use of different metal ions in studying the spirobenzopyran derivatives' photochroimism has been reported.

Research has been conducted on the phosphotriesterase isolated from Pseudomonas diminuta. The high-resolution X-ray structures of the substituted phosphotriesterase forms crystallized in the substrate analogues absence are described.

Research has been conducted on the molten globule intermediate of bovine carbonic anhydrase II. The dependence of the stability or unfolding of this intermediate on metal ion cofactor has been investigated.

Research has been conducted on the small GTPase Ras important for the intercellular signal transduction. The application of the high-field, high-frequency EPR spectroscopy to study the Ras.Mn (super)2+ .GDP complex at room temperature is described.

Research has been conducted on the quinone (Q (sub)B) reduction in Rhodobacter sphaeroides chromatophores. The effect of the metal ion binding on the electrogenic phases of electron transfer connected with the quinone reduction has been investigated via time-resolved electric potential changes.

Research has been conducted on the PvuII endonuclease active site variant. The analysis of this active site variant via two-dimensional NMR methods and stability measurements has been carried out.

The slow binding phenomenon elicited by metal ions appear to be a general case for malic enzyme in that alteration of its active site is unfavorable to catalysis. Data suggest that both manganese and chemical nature and correct coordination of the metal ions in the active site are catalytically essential.

Results demonstrate that the citrate transporter proteins CitM and CitH facilitate uptake of citrate and this activity is stimulated by divalent metal ions. Data suggest that the proteins actually transport complexes of divalent metal ions and citrate with a complementary metal ion specificity.