estimation of protein stability is important for many reasons: first providing an understanding of the basic thermodynamics of the process of folding, protein engineering, and protein stability plays important role in biotechnology especially in food and protein drug design. today, proteins are used in many branches, including industrial processes, pharmaceutical industry, and medical fields. a...

Two possible isomers of some 1,3-diaryl-H-benzo[f]chromene have been studied using density functional theory. Structures of E1 and E2 isomers were optimized at the B3LYP and MP2 levels with different basis sets. The total electronic energies show that E2 isomer is about 3-5 kcal/mol more stable than E1 isomer and this energy difference is attributed to the planarity of heterocyclic ring and mor...

Crystalline bovine or porcine glucagon was fractionated by chromatography on columns of DEAE-cellulose in the presence of buffers containing ‘7 M urea. About 89% of the recovered protein comprises highly purified glucagon; 10% is monodesamidoglucagon and another 0.8 % resembles glucagon in amino acid composition and in electrophoretic mobility. The monodesamidoglucagon was identified and charac...

the structures and stability of 531 novel boron nitride substituted isomers of 12-crown-4 etherverified theoretically. for a collection of 23 selected bn isomers, structural geometry, vibrationalstability, energy gaps, natural bond population analysis, and nonlinear optical responses investigatedtheoretically. the changes of standard enthalpies for ionization reactions and electron affinityreac...

A single antibody was shown to adopt different binding-site conformations and thereby bind unrelated antigens. Analysis by both x-ray crystallography and pre-steady-state kinetics revealed an equilibrium between different preexisting isomers, one of which possessed a promiscuous, low-affinity binding site for aromatic ligands, including the immunizing hapten. A subsequent induced-fit isomerizat...

Gas-phase electronic and structural properties of the room temperature ionic liquid 1-ethyl-3-methylimidazolium tris(perfluoroethyl)trifluorophosphate ([EMIM][FAP]) were studied using density functional theory, and confirmed with results from infrared spectroscopy. A conformational analysis allowed the identification of several plausible conformers of the ion pairs. For the detected conformers,...

The structures and stability of 531 novel boron nitride substituted isomers of 12-crown-4 etherverified theoretically. For a collection of 23 selected BN isomers, structural geometry, vibrationalstability, energy gaps, natural bond population analysis, and nonlinear optical responses investigatedtheoretically. The changes of standard enthalpies for ionization reactions and electron affinityreac...

In the present study, theoretical chemical reactivates Photo isomerization in Cis-Retinal as a Natural Photo switch in Vision. DFT hybrid functional, B3LYP and, post-HF method, were the theoretical methods applied utilizing G09 software. 6-31G+ (d,p) basis set employed for structural optimizations, and single point computations performed using B3LYP/6-31G+(d,p). The isomers cis molecule retinal...