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The syntheses and characterizations of a series of novel fluorotitanophosphates [(N[H.sub.4]).sub.x][K.sub.4-x][[Ti.sub.2]P[O.sub.4][F.sub.9]] (x = 0, 0.70, 1.00, 1.25) are described. The partial substitution of potassium by ammonium has shown that the structure has converted to a more-symmetric version, while maintaining all of the topological features.

The design and synthesis of a tandem protein kinase substrate peptide acting as a phosphate-mediated molecular memory is described. The analysis has shown that the information can be recorded on the substrate peptide by protein kinase-catalyzed phosphorylation and have provided clues for developing practical molecular-based processing and computing.

The systematic derivatization of polyethylene imine (PEI) with alkyl ([C.sub.2]-[C.sub.12]), benzyl, and guanidinium groups which gives rise to catalysts ('synzymes') with rate accelerations of up to [10.sup.4] for the intramolecular transesterification of 2-hydroxypropyl-p-nitrophenyl phosphate, HPNP, in the absence of metal is reported.

The study describes the directed evolution of 2-keto-3-deoxy-6-phosphogalactonate (KDPGal) aldolase, which is used to replace 3-deoxy-D-arabino-heptulosonic acid 7-phosphate synthase(DAHP) for the synthesis of various shikimate pathway products. The substance has proved to be a lot more advantageous and beneficial, as it gives rise to several other variants and can also coamplify with transketolase.

A divergent strategy employed for the synthesis of [alpha]-aryl-substituted fosmidomycin analogues, which are often used as the antimalarial drugs are described. The methodology is found to exhibit a palladium-catalyzed Stille coupling as the key step, as the antimalarial activity of the analogues are clearly found to surpass that of the reference compound fosmidomycin.

The discovery of a new inherited metabolic disorder, dolichol kinase (DK1) deficiency that is responsible for the final step of the de novo biosynthesis of dolichol phosphate, is described. The results have shown that two homozygous mutations in the human homologue of the yeast DK1 caused a lethal phenotype, with death in early infancy.

A study focuses on the enolpyruvylshikimate-3-phosphate synthase, EPSP (AroA), which is a carboxyvinyl transferase that helps in the biosynthesis of aromatic amino acid by using shikimate 3-phosphate and phosphoenolpyruvate. The analysis reveals that a large amount of catalytic power is used up by AroA for the formation of an EPSP cation, an intermediate which is a very easy target motif for inhibitor design.

Refocused MAS-J-INEPT NMR experiments in the solid state for the characterization of crystalline silicophosphate phases and amorphous gels are described. It is shown that [super 2][J.sub.P-O-Si] coupling constants are strongly dependent on the crystallographic chemical paths and on the number of (-OP) bonds around the Si atoms.

Parathyroid hormone (PTH) and PTH-related protein (PTHrP) are two factors that share amino acid sequence homology and act via a common receptor. In tetrapods, PTH is the main endocrine factor acting in bone and kidney to regulate calcium and phosphate. PTHrP is an essential paracrine developmental factor present in many tissues and is involved in the regulation of ossification, mammary gland development, muscle relaxation, and other functions. Fish apparently lack an equivalent of the parathyroid gland and were long thought to be devoid of PTH. Only in recent years has the existence of PTH-like peptides and their receptors in fish been firmly established. Two forms of PTH, two of PTHrP, and a protein with intermediate characteristics designated PTH-L are encoded by separate genes in teleost fish. Three receptors encoded by separate genes in fish mediate PTH/PTHrP actions, whereas only two receptors have so far been found in terrestrial vertebrates. PTHrP has been more intensively studied than PTH, from lampreys to advanced teleosts. It is expressed in many tissues and is present in high concentration in fish blood. Administration of this peptide alters calcium metabolism and has marked effects on associated gene expression and enzyme activity in vivo and in vitro. This review provides a comprehensive overview of the physiological roles, distribution, and molecular relationships of the piscine PTH-like peptides. parathyroid hormone-related protein; calcium regulation; phosphate regulation; molecular evolution

The synthesis of a lithium gadolinium phosphate crystal, Li[Gd.sub.5][P.sub.5][O.sub.13] was carried out by a high temperature solution reaction and solved by single-crystal X-ray diffraction data. Li[Gd.sub.5][P.sub.5][O.sub.13] presents a new structural type and is built up from [[Gd.sub.5][P.sub.2][O.sub.13]].sup.-] layers and one-dimensional Li chains with an unusual Li-Li distance.

A new layered fluoroaluminophosphate [([C.sub.4][H.sub.11]NOH).sub.3.5][[Al.sub.4][(P[O.sub.4]).sub.5]F].0.5[H.sub.3]O denoted as AlPO-CJ20 with an Al/P ratio of 4:5 was solvothermally synthesized by using 2-amino-2-methyl-1-propanol as the template in the presence of [F.sup.-] ions. The alternation of Al-centered tetrahedra (Al[O.sub.4] and Al[O.sub.3]F) and P[O.sub.3](=O) tetrahedra gives rise to a new type of 4.6 16-net sheet.

The synthesis of single crystals of three new layered uranium phosphate fluorides A(U[O.sub.2])F(HP[O.sub.4]).x[H.sub.2]O (A = C[s.sup.+], [Rb.sup.+]; X = 0-1) was carried out by hydrothermal reactions using U[O.sub.3], [H.sub.3]P[O.sub.4], HF, and corresponding alkali metal halides as reagents. The experiments demonstrates that the ion exchange of A(U[O.sub.2]F(HP[O.sub.4])*x[H.sub.2]O materials not only provide a facile route for the low-temperature synthesis of layered alkali-metal uranium phosphate materials but also suggest how the structural diversity of the uranium layered materials could be tuned with different cations.

A study is presented to demonstrate that a ribonucleic acid (RNA)-capping ribozyme retains stereochemistry at a phosphorus reaction center. The retention of stereochemistry and kinetics implies that capping utilizes two inverting chemical steps that are separated by the transient formation of a rate-limiting covalent intermediate, and since all protein enzymes that mediate similar capping reactions utilize a covalent intermediate, chemical necessity may guide the evolution of both protein and RNA-capping catalysts.

The first example of a supramolecular stereocontrol over the propellar geometry of triarylalkylphosphonium cation, both in solution and in the solid state is described. The asymmetric ion pairing allowed a most simple experimental proof of the nature of the enantiomerization pathway in solution (two-ring flip).

The correlation of indirect NMR spin-spin coupling constants [.sup.3.J](P,C) and [.sup.2.J](P,H) with a local topology of the P-O...H-C motif is determined. Measuring of these coupling constants can provide critical constraints on the nucleic acid (NA) base and phosphate geometry and also help to determine the structure of NAs.

A report is presented on the synthesis of two new derivatives of 1,4,7-triazacyclononate and their use in the preparation of 'roof-shaped' hydroxo-bridged copper(ll) complexes, in which the (Cu2(mu-OH)2)(super 2+) core is asymmetric and the two Cu-tacn moieties adopt a syn configuration across the hydroxo-bridged core. The ability of these complexes to cleave phosphate ester is examined, which has involved the study of the reaction of the complexes with the model phosphate ester, bis(nitrophenyl)phosphate (BNPP).

A new copper(II) phosphate phase, Cs2Cu3P4O14 (1) was isolated employing the mixed CsCl/2Csl molten flux, in the exploratory synthesis of compounds containing transition-metal oxide magnetic nanostructures. The synthesis, structure and the magnetic properties of the new family of copper(ll) phosphates, C(sub 2-x)Rb(sub x)Cu3P4O14 (0.0

The first two low-dimensional beryllium phosphates compounds, [C5H14N2]2[Be3(HPO4)5].H2O (BePO-CJ29) and [C6H18N2]0.5[Be2(PO4)(HPO4)OH]-0.5H2O (BePO-CJ30), are successfully synthesized under mild hydrothermal/solvothermal conditions. The solvent has an important effect on the morphology of the crystals of BePO-29, and the additive TEOS favors the formation of high-quality large single crystals of BePO-CJ30.

A study to investigate the structure and desorption dynamics of thin D(sub 2)O overlayers deposited on serine- and serinephosphate- terminated self-assembled monolayers (SAMs) is conducted. The reflection absorption spectra obtained at sub-monolayer D(sub 2)O coverage reveals that surface modes dominate on the serine SAM surface, whereas vibrational modes characteristic for bulk ice are more prominent on the serinephosphate SAMs.

The two-step intercalation mechanism that can induce intercalated structures of hexadecylamines (HDAs), either in bilayers or in interdigitated layers, in the confined space of highly fictionalized layered alpha-ZrP intergalleries is demonstrated. A structural transition from the bilayers to the interdigitated layers is monitored by using in situ synchrotron WAXS showing that the hydrophobically intercalated HDAs are selectively deintercalated at a relatively low decomposition temperature around 220 degree Celsius.

A study to describe the synthesis of aluminophosphate (AlPO-5) and silicoaluminophosphate (SAPO-5) material (AFI topology) using five different tertiary amines or quaternary ammonium ions containing one or two benzyl rings as structure-directing agents was conducted. The results of atomic modeling revealed that the templates of benzyl ring self-assemble in the main AFI channel forming dimers with the benzyl ring parallel to each other.

The synthesis and properties of a nucleic acid analogue consisting of a benzene-phosphate backbone are described. The building blocks of the nucleic acid analogue are composed of bis(hydroxymethyl)-benzene residues connected to nucleobases via the biaryl-like axis.

3-Deoxy-D-arabino-heptulosonate-7-phosphate synthase (DAH7PS) catalyzes the condensation reaction between phosphoenolpyruvate (PEP) and the four-carbon monosaccharide D-erthyrose 4-phosphate (E4P). The broad specificity of the DAH7PS, the lack of allosteric inhibition, and various structural features indicate that of the enzymes Pyrocossus furiosus DAH7OPS might be the contemporary protein closest to the ancestral type I enzyme.

A new three-dimensional open-framework aluminophosphate (NH4)2AI4(PO4)4(HPO4).H2O with an AI/P ratio of4/5 is synthesized using pyridine as the solvent and 2-aminopyridine as the structure directing under solvothermal conditions. The structure was determined by single-crystal X-ray diffraction and further characterized by solid-state NMR techniques.

An investigation is conducted for the purpose of amalgamating zinc phosphates adorned by ancillary ligands, and to simultaneously comprehend the function of the ligands in constructing these solids. The fusion, composition and description of four new zinc phosphates are presented.

An extensive examination of the catalytic mechanism proposed for orotidine 5'-monophosphate decarboxylase (ODCase) is reported. The decarboxylation is accompanied by the movement of a fully conserved lysine residue toward the developing negative charge at the C6 position.

Conjugate bases of phosphoric acid form adducts with the hexaazamacrocycle, [18]aneN6, the composition of which varies with the ph of crystallization. At higher ph, the addition of water aids in the formation of stable structures.

Melaminium dihydrogenpyrophosphate obtained as a crystalline powder by thermal treatment of melaminium dihydrogenphosphate is the first intermediate in the synthesis of polymerized melamine phosphates. The crystal structure of MPy is determined by X-ray powder diffraction and the proposed hydrogen-bonding model is corroborated by solid-state NMR and periodic DFT calculations.

Polyphosphate ions are found to react easily with cyclic oxothiomolybdic backbone, allowing the formation of encapsulated substrates. Their molecular composition, formed in the solid phase, explains the versatility and abilities of these compounds.

The x-ray structure of human soluble epoxide hydrolase (sEH) reveals a domain-swapped quaternary structure. Soluble epoxide hydrolase is important in biology because of its activity against lipid epoxide substrates and its localization in liver, kidneys and vascular tissues.

A new class of orthogonal triphosphate substrate analogue for the direct labeling of analogue-specific kinase protein targets is described. Kinase mutation selection may require iterative rounds of optimization for activity as well as for specificity toward the analogue, and may involve second site mutations, which make the kinase more susceptible to the inhibitors or inhibitor based triphosphate analogues.

The studies revealed that squalene synthase (SQase) catalyzes two consecutive reactions in sterol biosynthesis. The first is the condensation of two molecules of famesyl diphosphate (FPP) to form acyclopropylcarbinyl intermediate, presqualene diphosphate (PSPP). It is concluded that the catalytic machinery of the enzyme can synthesize 1'-1 compounds typical of those seen in the sterol and carotenoid biosynthetic pathways, as well as the 1'-3 structures found in botryococcene.

The study revealed that squalene synthase (SQase) catalyzes the condensation of two molecules of farnesyl diphosphate (FPP) to form presqualene diphosphate (PSPP) and the subsequent rearrangement of NADPH-dependent reduction of PSPP to squalene (SQ). The study compared the SQase-catalyzed solvolysis of PSPP in the absence of NADPH(sub 3) to the reaction in the presence of NADPH(sub 3), and stated that it is apparent that the binding of the cofactor analogue substantially enhances the ability of SQase to control the regio-and stereochemistry of the rearrangements of PSPP.

The study represents the first detection of a tridentate coordination mode for triphosphate in solution. It has utilized advanced electron spin echo modulation and four-pulse- two-dimensional hyperfine sublevel correlation spectroscopic techniques to characterize the solution structure of the 1:1 triphosphate.

Researchers demonstrated the utility of the phosphate in generating very short and very strong C-HaO, N-HaO and O-HaO hydrogen bonds .A distances are in the range of shortest known hydrogen bonds in their respective categories. The phosphate assisted strong C-HaO interaction was observed which could have effect on anaresidues. The pseudopolymorphism exhibited should make the cyclic phosphate a promising substrate for hydrogen bonding.

Five new open-framework zinc phosphates, encompassing the entire hierarchy of open-framework structures are synthesized hydrothermally in the presence of a tetramine, triethylenetetramine. The structure of the open-framework zinc phosphates depends on the relative concentrations of the amine and phosphoric acid, with high concentrations of the latter favoring structures with lower dimensions.

We present the study on the structural and the magnetic properties of LiFeP[O.sub.4] and Li[Fe.sub.0.8] [Co.sub.0.2]P[O.sub.4]. The crystal structure was determined to be orthorhombic with space group Pnma by Rietveld refinement method. We have observed the increase in the lattice constants with [Co.sup.2+] ion substituted. The Mossbauer spectra of olivine LiFe[P[O.sub.4] and Li[Fe.sub.0.8][Co.sub.0.2]P[O.sub.4] have shown distorted line broadening below [T.sub.N]. In order to explain the observed line broadening, we have analyzed the Mossbauer spectra by considering the full Hamiltonian for the [sup.57]Fe nucleus, and both the magnetic dipole and the electric quadrupole interactions. Also, we have observed the anomalous change in the electric quadrupole splitting near the [T.sub.N]. Index Terms--Crystal field, Mossbauer spectroscopy, olivine structure.

The novel tetranuclear copper(II) complexes with alpha-D-glucose-1-phosphates, [Cu(sub 4)(mu-OH)(alpha-D-Glc-1P)(sub 2)(L)(sub 4)(H2O)2(sub 2)](NO3)(sub 3) were prepared and characterized by X-ray crystallography. Complex [Cu(sub 4)(mu-OH)(alpha-D-Glc-1P)(sub 2)(L)(sub 4)(H2O)2(sub 2)](NO3)(sub 3) was revealed to be a good precursor of the adenosine 5'-triphosphate (ATP) stabilized tetranuclear Cu(super II) complex of [Cu4(ATP)2(bpy)4].

High-nuclearity metal clusters were assembled to devise multidentate tripodal ligands, N[(C[H.sub.2]-m-[C.sub.6][H.sub.4]-C[H.sub.2]tacn).sub.3] and N[(C[H.sub.2]-o-[C.sub.6][H.sub.4]-C[H.sub.2]N[(C[H.sub.2]py).sub.2]).sub.3]. The results demonstrated the propensity of both the novel tripodal ligand platform, in the presence of phosphate or arsenate, to assemble {[M.sub.3](E[O.sub.4])} units and thus structurally mimic trimetallic active sites of proteins involved in phosphate metabolism.

A combined nuclear magnetic resonance (NMR) experimental and periodic density functional theory (DFT) computational study of the environments and periodic density functional theory (DFT) computational study of the environments and electronic structures occurring in a range of paramagnetic Fe(III) phosphates is described. The [super 31]P spin-echo mapping and [super 7]Li magic angle spinning NMR methods have produced the hyperfine shifts of the species of interest, which is complemented by periodic hybrid functional DFT calculations of the respective hyperfine and quadrupolar tensors.

[Super 31]P NMR was employed to establish that EDAC (1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide)-mediated reactions between primary amines and polyphosphate result in phosphoramidate linkages with the terminal phosphate groups. The findings from the study provide new pathways for the entire armamentarium of protein chemistry to modifying polyphosphate and conduct future studies to understand its biological roles.

Enigmazole A, a novel phosphate-containing macrolide, is isolated from a Papua New Guinea marine sponge Cinachyrella enigmatica and its structure and absolute stereochemistry are determined. The enigmazoles are the first phosphomacrolides from a marine source and enigmazole A has displayed cytotoxicity in the NCI 60-cell line antitumor screen, with a mean G[I.sub.50] of 1.7 [micro]M.

A detailed study was conducted for structural characterization and stereochemistry determination of a new sesquiterpene alcohol avermitilol obtained through the incubation of the recombinant protein, SAV_76, with farnesyl diphosphate in the presence of [Mg.sup.2+]. The finding offers insight into the biochemical function of the terpene synthase encoded by the sav76 gene of Streptomyces avermtilis which was expressed in Escherichia coli as an N-terminal-[His.sub.6]-tag protein.

The synthesis and decomposition kinetics of a series of phosphate mono-, di-, and triesters with a common leaving group (LG) (2'-(2-phenoxy)-1,10-phenanthroline) and their Cu(II) complexes are described. The energy in the obtained products resulting from P-O(LG) cleavage are found to be the driving force for the catalyzed reactions.

A total synthesis of phostriecin (sultriecin), its structural reassignment as a phosphate versus sulfate monoester and the assignment of its relative and absolute stereochemistry are described. The key elements of the work has depended on diagnostic [super 1]H NMR spectroscopic properties of the natural product for the assignment of relative and absolute stereochemistry as well as the subsequent structural reassignment and a convergent asymmetric total synthesis to provide the authentic materials.

The preparation of a new phosphate carbenoid [(n-BuO).sub.2]P(O)OZn[CH.sub.2]I and its application in organozinc-mediated reactions is described. The application of obtained carbenoid in the chain extension of 1,3-diketones and [2,3]-sigmatropic rearrangement reactions is also described.