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Bonding Properties (bond + property)
Selected AbstractsTyrosine Hydrogen Bond Properties for the Two Binding Sites of ApoovotransferrinCHINESE JOURNAL OF CHEMISTRY, Issue 10 2005Ying-Qi Li Abstract The interaction of gallium(III) with the ligands containing phenolic group(s), such as salicylic acid, 8-hydroxyquinoline, N,N' -bis(2-hydroxybenzyl)ethylenediamine- N,N, -diacetic acid (HBED), N,N, -ethylenebis[2-(o -hydroxyphenyl)glycine (EHPG), and ovotransferrin, was studied, respectively, by means of fluorescence in 0.01 mol/L Hepes at pH 7.4 and room temperature. Fluorescence intensity showed an increase when gallium(III) was bound to 8-hydroxyquinoline and HBED. In contrast, it was decreased with the interaction of gallium(III) with salicylic acid and EHPG. At pH 7.4, there was N···HO type intramolecular hydrogen bond in the former, and the latter existed O···HO type intramolecular hydrogen bond. Fluorescence titration of apoovotransferrin with gallium(III) displayed that the fluorescence intensity was decreased at the N-terminal binding site, while enhanced at the C-terminal binding site. It can account for the O···HO type intramolecular hydrogen bonds for the phenolic groups of Tyr92 and Tyr191 residues at the N-terminal binding site. And there are N···HO type intramolecular hydrogen bonds for Tyr431 and Tyr524 residues at the C-terminal binding site. In addition, under the same conditions, the conditional binding constant of gallium(III) with EHPG or HBED determined by fluorescence method is lg KGa-EHPG=19.18 or lg KGa-HBED=19.08. [source] Novel Barium Beryllates Ba[Be2N2] and Ba3[Be5O8]: Syntheses, Crystal Structures and Bonding Properties.CHEMINFORM, Issue 44 2005Stefano Leoni Abstract For Abstract see ChemInform Abstract in Full Text. [source] Unusual Electronic and Bonding Properties of the Zintl Phase Ca5Ge3 and Related Compounds.CHEMINFORM, Issue 26 2004A Theoretical Analysis Abstract For Abstract see ChemInform Abstract in Full Text. [source] Small Cluster Models of the Surface Electronic Structure and Bonding Properties of Titanium Carbide, Vanadium Carbide, and Titanium NitrideCHEMINFORM, Issue 4 2004Stephen V. Didziulis Abstract For Abstract see ChemInform Abstract in Full Text. [source] Structural, Electronic, and Bonding Properties of Zeolite Sn-Beta: A Periodic Density Functional Theory StudyCHEMISTRY - A EUROPEAN JOURNAL, Issue 2 2006Sharan Shetty Abstract The structural, electronic, and the bonding properties of the zeolite Sn-beta (Sn-BEA) have been investigated by using the periodic density functional theory. Each of the nine different T-sites in BEA were substituted by Sn atoms and all the nine geometries were completely optimized by using the plane-wave basis set in conjunction with the ultra-soft pseudopotential. On the basis of the structural and the electronic properties, it has been demonstrated that the substitution of Sn atoms in the BEA framework is an endothermic process and hence the incorporation of Sn in the BEA is limited. The lowest unoccupied molecular orbitals (LUMO) energies have been used to characterize the Lewis acidity of each T-site. On the basis of the relative cohesive energy and the LUMO energy, the T2 site is shown to be the most favorable site for the substitution Sn atoms in the BEA framework. [source] What is the biological relevance of the specific bond properties revealed by single-molecule studies?,JOURNAL OF MOLECULAR RECOGNITION, Issue 6 2007Philippe Robert Abstract During the last decade, many authors took advantage of new methodologies based on atomic force microscopy (AFM), biomembrane force probes (BFPs), laminar flow chambers or optical traps to study at the single-molecule level the formation and dissociation of bonds between receptors and ligands attached to surfaces. Experiments provided a wealth of data revealing the complexity of bond response to mechanical forces and the dependence of bond rupture on bond history. These results supported the existence of multiple binding states and/or reaction pathways. Also, single bond studies allowed us to monitor attachments mediated by a few bonds. The aim of this review is to discuss the impact of this new information on our understanding of biological molecules and phenomena. The following points are discussed: (i) which parameters do we need to know in order to predict the behaviour of an encounter between receptors and ligands, (ii) which information is actually yielded by single-molecule studies and (iii) is it possible to relate this information to molecular structure? Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||