reaction mechanism ͉ DNA ͉ RNA ͉ density functional theory ͉ gas phase model

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Complementary experimental and theoretical studies presented in this work examine the structure, organization, and solvating properties of methanol at a silica/methanol, solid/liquid interface. Findings from these experiments illustrate how strong association between a silica substrate and methanol solvent creates a distinctly nonpolar solvation environment for adsorbed solutes. Resonance-enhanced second-harmonic spectra and time-resolved fluorescence emission in a total internal reflection geometry both show that adsorbed solutes sample an interfacial environment having properties resembling those of a nonpolar solvent. Molecular dynamics simulations identify the origin of this effect. Strong hydrogen bonding between the first layer of methanol and silica’s silanol groups creates what is effectively a methyl-terminated surface that leads to a second layer having significantly reduced density and hydrogen bonding compared to bulk solution. The calculated solvent reorientation times in these first two layers is significantly slower than in bulk, implying slow dielectric relaxation and supporting both second-harmonic and time-resolved fluorescence results. Collectively, these studies illustrate how surface-induced changes in solvent structure change the chemistry at strongly associating solid/liquid interfaces as compared to bulk solution limits.

In view of the growing importance of reversed hazard rate (RHR) in reliability analysis and stochastic modeling, we have considered different implicative relationships with respect to the monotonic behavior of RHR. In that context, a few characterizing properties have also been presented based on expected inactivity time.

PurposeThe end‐state of marketing is the creation of a lasting bond between the consumers and the offered brand. In view of the growing competition in the market, a never‐ending brand war can be witnessed that attempts to destabilize the consumer‐brand bonding. To ensure a long‐run success, there is a need to develop a system approach towards proper integration of a brand's identity with its image. This paper seeks to address this issue.Design/methodology/approachThe major task is to identify the gap and skilful integration of brand identity with brand image to cement the gap. Improper integration may lead to a major setback in the market and irreparable loss. The authors present a verbal model as the basis for integration so that the chance of a setback becomes minimal.FindingsThe authors propose a Brand Derby Matrix, a classification cum decision matrix to enable a marketer to identify its present position and future course of action, in conjunction with the Credibility‐Alteration‐Relationship‐Expansion (CARE‐ing) strategy to address the above‐mentioned issue.Practical implicationsBrand Derby Matrix in conjunction with the CARE‐ing strategy can be of immense use to brand planners for identification and managing of the problem to ensure smooth sailing in the market.Originality/valueIn this paper, the authors present a generic approach that may work beyond country boundaries. Brand Derby Matrix in conjunction with the CARE‐ing strategy is immensely helpful in addressing the dilemma of brand identity and brand image integration issues that are faced by players.

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The molecular basis of salt tolerance of L-myo-inositol 1-P synthase (MIPS; EC 5.5.1.4) from Porteresia coarctata (Roxb.) Tateoka (PcINO1, AF412340) earlier reported from this laboratory, has been analyzed by in vitro mutant and hybrid generation and subsequent biochemical and biophysical studies of the recombinant proteins. A 37-amino acid stretch between Trp-174 and Ser-210 has been confirmed as the salt-tolerance determinant domain in PcINO1 both by loss or gain of salt tolerance by either deletion or by addition to salt-sensitive MIPS(s) of Oryza (OsINO1) and Brassica juncea (BjINO1). This was further verified by growth analysis under salt environment of Schizosaccharomyces pombe transformed with the various gene constructs and studies on the differential behavior of mutant and wild proteins by Trp fluorescence, aggregation, and circular dichroism spectra in the presence of salt. 4,4#-Dianilino-1,1#-binaphthyl-5,5-disulfonic acid binding experiments revealed a lower hydrophobic surface on PcINO1 than OsINO1, contributed by this 37-amino acid stretch explaining the differential behavior of OsINO1 and PcINO1 both with respect to their enzymatic functions and thermodynamic stability in high salt environment. Detailed amino acid sequence comparison and modeling studies revealed the interposition of polar and charged residues and a well-connected hydrogen-bonding network formed by Ser and Thr in this stretch of PcINO1. On the contrary, hydrophobic residues clustered in two continuous stretches in the corresponding region of OsINO1 form a strong hydrophobic patch on the surface. It is conceivable that salt-tolerant MIPS proteins may be designed out of the salt-sensitive plant MIPS proteins by replacement of the corresponding amino acid stretch by the designated 37-amino acid stretch of PcINO1.

The homopteran sucking insect, Lipaphis erysimi (mustard aphid) causes severe damage to various crops. This pest not only affects plants by sucking on the phloem, but it also transmits single-stranded RNA luteoviruses while feeding, which cause disease and damage in the crop. The mannose-binding Allium sativum (garlic) leaf lectin has been found to be a potent control agent of L. erysimi. The lectin receptor protein isolated from brush border membrane vesicle of insect gut was purified to determine the mechanism of lectin binding to the gut. Purified receptor was identified as an endosymbiotic chaperonin, symbionin, using liquid chromatography-tandem mass spectrometry. Symbionin from endosymbionts of other aphid species have been reported to play a significant role in virus transmission by binding to the read-through domain of the viral coat protein. To understand the molecular interactions of the said lectin and this unique symbionin molecule, the model structures of both molecules were generated using the Modeller program. The interaction was confirmed through docking of the two molecules forming a complex. A surface accessibility test of these molecules demonstrated a significant reduction in the accessibility of the complex molecule compared with that of the free symbionin molecule. This reduction in surface accessibility may have an effect on other molecular interactive processes, including "symbionin virion recognition", which is essential for such symbionin-mediated virus transmission. Thus, garlic leaf lectin provides an important component of a crop management program by controlling, on one hand, aphid attack and on the other hand, symbionin-mediated luteovirus transmission.