Structural explanation

Although Pasteur was unable to provide a structural explanation—that had to wait for van t Hoff and Le Bel a quarter of a century later—he correctly deduced that the enantiomeric quality of the crystals was the result of enantiomeric molecules The rare form of tartanc acid was optically inactive because it contained equal amounts of (+) tartaric acid and (—) tartaric acid It had earlier been called racemic acid (from Latin racemus meaning a bunch of grapes ) a name that subsequently gave rise to our pres ent term for an equal mixture of enantiomers... 

SY Chung, S Subbiah. A structural explanation for the twilight zone of protein sequence homology. Structure 4 1123-1127, 1996. 

Develop a structural explanation for die existence of diis barrier in bodi resonance and molecular oibital terminology. 

A large number of compounds of pharmaceutical interest are capable of being crystallized in either more than one crystal lattice structure (polymorphs), with solvent molecules included in the crystal lattice (solvates), or in crystal lattices that combine the two characteristics (polymorphic solvates) [122,123]. A wide variety of structural explanations can account for the range of observed phenomena, as has been discussed in detail [124,125]. The pharmaceutical implications of polymorphism and solvate formation have been recognized for some time, with solubility, melting point, density, hardness, crystal shape, optical and electrical properties, vapor pressure, and virtually all the thermodynamic properties being known to vary with the differences in physical form [126]. 

Stewart D. B. and Ribbe P. H. (1969). Structural explanation for variations in cell parameters of alkali feldspars with Al/Si ordering. Amer Jour Sci., 267A 444-462. 

Using a similar approach, Notman et al. [81], determined the free energy for pore formation in bilayers composed of ceramide, as a model for the stratum corneum of the skin, both in the presence and in the absence of DMSO. Without DMSO, the bilayer was in the gel phase, and interestingly, a hydrophobic pore was observed with a high free-energy barrier ( 60 kj/mol). In the presence of DMSO, the bilayer was more fluid, and the more typical hydrophilic pore was observed, with a much smaller activation energy of 20kJ/mol. This work provided a thermodynamic and structural explanation for the enhanced permeability of skin by DMSO. 

McPeeters RL, Oswald RE (2004) Emerging structural explanations of ionotropic glntamate receptor function. FASEB J 18 428-438... 

Based on experimental evidence from AFM, the physical mechanism of orogenic5 displacement was proposed (Mackie et al., 1999b, 2000, 2003). A crucial aspect of the mechanism is that the surfactant domains exert a lateral surface pressure which compresses the protein layer. The AFM data obtained by Mackie and co-workers (1999b) provided direct visual evidence, for the first time, of a gel-like protein network at the air-water interface, as well as a structural explanation of protein displacement by small-molecule surfactant. In essence, the process of orogenic5 displacement is assumed to involve three stages ... 

Over time, the research interests of the Rice University team and of Kroto were directed increasingly to developing a suitable structural explanation of the even-numbered carbon clusters and. notably, of the Cm molecule. 

Note added in proof The structure of tubulin in complex with two other vinca domain ligands, namely with soblidotin, a dolastatin 10 analog, and with phomopsin A, has now been determined. These new results show that the site of these molecules overlaps only in part with the one of vinblastine. They put a structural explanation for the different properties of these compounds (e.g. an higher efficiency to inhibit the nucleotide exchange on tubulin) as compared to vinblastine [72]. 

The outer sphere changes will undoubtedly effect not only changes in AH and AS but in ACP as ACp is large for water itself. If the above description of the nature of lanthanide ions is correct then a structural explanation of their properties must be replaced by a statistical mechanical picture. It is this picture which I wish to carry over into the discussion of the uses of lanthanide ions as probes in biological systems, and therefore I wish to examine it in more detail. 

Figure 9. A possible structural explanation for the influence of heat on the functional proper-...

McFeeters, R. L., and Oswald, R. E. (2004). Emerging Structural Explanations of Ionotropic Glutamate Receptor Function. FASEBJ. 18, 428-438. 

At a fixed temperature, the only parameter determining the mean hole size is the surface tension. Though one is aiming at a microscopic (structural) explanation of the behavior of ionic liquids, one goes ahead and uses the macroscopic value of surface tension. The mean hole radius then turns out to have the same order of magnitude as the mean radius of ions comprising the liquid. 

Tu D, Blaha G, Moore PB, Steitz TA. Structures of MLSBK antibiotics bound to mutated large ribosomal subunits provide a structural explanation for resistance. Cell 2005 121 257-270. Hansen JL, Ippolito JA, Ban N, Nissen P, Moore PB, Steitz TA. The structures of four macrolide antibiotics bound to the large ribosomal subunit. Mol. Cell 2002 10 117-128. 

Part of solid state chemistry is presently involved with what is called soft chemistry or soft materials. As a matter of fact these are not expected to luminescence, at least not when the luminescent centers are broadband emitters. This has been shown to be the case, for example, for the isomorphous Al2(W04)3, Sc2(W04)3, and Zr2(P04)2S04. The Stokes shift of the tungstate and zirconate luminescence in these materials is enormous, viz., some 2 eV. The quantum efficiencies, even at 4.2 K are low (101). The exact structural explanation has been discussed in the literature (101). 

Salminen T, Varis M, Nyronen T, et al. Three-dimensional models of a2A-adren-ergic receptor complexes provide a structural explanation for ligand binding. J Biol Chem 1999 274 23,405-23,413. 

The crystal structure of the FluA fluorescein complex also provides a structural explanation for the strong quenching effect of this particular anticalin that was mentioned before. Tight coplanar packing of the indole ring of I rp against the xanthenolone system of the bound fluorescein was observed (Fig. 8.4). Consequently, this aromatic residue is the likely candidate for the highly efficient electron-transfer process and is optimally positioned in this respect. 

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