Structural determinations for

Lambright, D.G., et al. Structural determinants for activation of the a-subunit of heterotrimeric G protein. Nature 369 621-628, 1994. 

The structures determined for hematite and corundum show that these crystals consist of a compact arrangement of approximately, but not exactly, spherical ions of oxygen and of iron or aluminum, held together by inter-ionic forces which are prob- atoms in the units of structure of ably electrostatic in nature. No evidence hematite and corundum small cir-... 

Structure determinations for YB4 (x-ray) and ErB4 (neutron) confirm the structure described above and indicate that the length of the B—B bonds between two octahedra is shorter than the length of the B—B bonds in an octahedron. Moreover, Er and B atoms exhibit a strong anisotropic thermal movement in ErB4... 

Elder, R.C., Ludwig, K, Cooper, J.N. and Eidsness, M.K (1985) EXAFS and WAXS structure determination for an antiarthritic drug, sodium gold(l) thiomalate. Journal of the American Chemical Society, 107, 5024—5026. 

The neuropeptide Y (NPY) belongs to a family of peptides that includes peptide YY and pancreatic polypeptide, and it is associated with several diseases such as asthma, immune system disorders, inflammatory diseases, anxiety, depression and diabetes mellitus. NPY is found in the central and peripheral nervous system, and its biological functions are mediated by interactions with five receptor sub-types, i.e. Yl, Y2, Y4, Y5 and Y6. Several studies indicate that the feeding behavior is influenced by interactions between NPY and Yl and Y5. Deswal and Roy used Cerius descriptors and genetic function approximation QSAR to investigate the structural determinants for the inhibition potency of 24 compounds with the general structure 4 for the NPY Y5 receptor [31]. The best QSAR (H = 0.720,... 

Principles and Characteristics Traditional analytical approaches include off-line characterisation of isolated components, and the use of several chromatographic separations, each optimised for a specific spectroscopic detector. Neither LC-NMR nor LC-MS alone can always provide complete structure determinations. For example, MS may fail in assigning an unequivocal structure for positional isomers of substituents on an aromatic ring, whereas NMR is silent for structural moieties lacking NMR resonances. Often both techniques are needed. 

Piomelli D, Beltramo M, Glasnapp S, Lin SY, Goutopoulos A, Xie XQ, Makriyannis A. Structural determinants for recognition and translocation by the anandamide transporter. Proc Natl Acad Sci USA 1999 10 5802-5807. 

Although low energy structures for prephenate have been reported before [40], these have been optimized using gas-phase quantum mechanics, and are not compatible with the structure determined for the prephenate inside the active site of CM [41], The first calculation of the electronic spectrum of prephenate inside the active site of the enzyme was done by our group [18]. Using the MD/QM method described, we were also able to obtain an electronic spectrum for prephenate in solution. 

The zinc teflate Zn(OTeF5)2 has been synthesized and characterized by IR and 19F NMR spectroscopy. The interaction with a number of weakly coordinating solvents was studied and the single-crystal X-ray structures determined for nitrobenzene derivatives [Zn(OTeF5)2 (PhN02)2]2 and Zn(0TeF5)2(PhN02)3.428... 

Zinc boryloxides with a tetrameric Zn404 core (45) have only recently been characterized. The single-crystal X-ray structure and multinuclear NMR spectroscopy studies were used as a basis for discussion of deformation of the central core.435 Alkali metal zinc orthoborates MZn4(B03)3 (M = K, Rb, Cs) have been synthesized and single-crystal X-ray structures determined for M = K and Rb.436... 

We have recently investigated X-ray structure of 3-methoxycarbonyl-[l,4,2] diazaphospholo[4,5-a]pyridine as first example of molecular structure determination for [l,4,2]diazaphosphole ring [84], The ester substituent lies strictly in the molecular plane with carbonyl group in the trans orientation with the formal C=P bond. Endocyclic P-N and P-C bonds are averaged between respective single and double bond lengths. 

G. Fischer et al. Decisive structural determinants for the interaction of proline derivatives with the intestinal H+/peptide symporter., Eur. J. 

Very powerful tools for the study of dienes and, to some extent, polyenes (in particular annular polyenes) are both H and 13 C NMR spectroscopies, which will be discussed in a separate section. As previously mentioned 1,3-butadiene is more stable in the s-trans conformation and in the H NMR spectrum both butadiene (1) and 2,3,6,7-tetramethyl-2,4,6-octatriene (3) display the vinyl proton at a low chemical shift value. In these simple examples the S value can be predicted theoretically. The 111 NMR spectrum of a C25-branched isoprenoid was examined as part of the structural determination for biomarkers and is shown in Figure l6. The other spectral and structure assignments are described later in this review. 

Mundell, S. J., Pula, G., Carswell, K., Roberts, P. J., and Kelly, E. (2003) Agonist-induced internalization of metabotropic glutamate receptor 1A structural determinants for protein kinase C- and G protein-coupled receptor kinase-mediated internalization../. Neurochem. 84,294-304. 

Fig. 3.17. The chemical structures determined for the dye components of BCDP using NMR and MS. Reprinted with permission from G. A. Umbuzeiro et al. [97).

There are four other proteins - stellacyanin, rusticyanin, umecyanin and ami-cyanin (Table 3) which have been fairly extensively studied. A crystal structure determination for amicyanin from Thiobacillus versutus is now under way [61]. A number of other type 1 proteins have been identified. These include pseudo-... 

Mueller, T. D. and Fbigon, J. Structural determinants for the binding of ubiquitin-like domains to the proteasome. Embo J 2003, 22, 4634-45. 

The complexity of the solvable structure strongly depends on the spectral resolution of the diffraction method in use. Structures with about 60 atoms in the asymmetric unit were solved from powder data combining synchrotron X-ray diffraction with refinement from neutron diffraction data from the same material (Morris et al. 1994 Admans 2000). About half of that complexity can be achieved with good laboratory X-ray diffractometers (Masciocchi et al. 1996 Kariuki et al. 1999). Neutron diffraction data can better be used for structure refinement than for structure determination, for the same reason. 

Black B.E., Foltz D.R., Chakravarfhy S., Luger K., Woods V.L. Jr, Cleveland D.W Structural determinants for generating centromeric chromatin. Nature 2004, 430, 578-582. 

Melnyk R.A., Hewitt K.M., Lacy D.B., Lin H.C., Gessner C.R., Li S., Woods V.L. Jr, Collier R.J. Structural determinants for the binding of anthrax lethal factor to oligomeric protective antigen. J. Biol. Chem. 

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