The self-assembled supramolecular structures of diacylphosphatidylcholine (diCnPC), diacylphosphatidylethanolamine (diCnPE), diacylphosphatidyglycerol (diCnPG), and diacylphosphatidylserine (diCnPS) were investigated by P nuclear magnetic resonance (NMR) spectroscopy as a function of the hydrophobic acyl chain length. Short-chain homologs of these lipids formed micelles, and longer-chain homolo...

T he field of asymmetric catalysis is dedicated to the development of efficient catalytic methods for the construction of chiral molecules and has been dominated by the use of organometallics and enzymes for most of its history. However, in the past decade, the concept of organocatalysis has emerged as a discrete strategy for addressing modern day challenges in chemistry. It has become widely a...

hydrogen bonding is considered by many to be the ‘master key’ of molecular recognition — owing to its relatively predictable strength and directionality — and plays a major role in the assembly of diverse non-covalent assemblies1. Consequently, the study and exploitation of hydrogen bonds has been central to the development of modern supramolecular chemistry. In particular, numerous applied set...

Using Hartree–Fock (HF) and ِِDensity Functional Theory (DFT) calculations the thermodynamic properties such as thermal energy , , thermal enthalpy , , thermal entropy , , thermal Gibbs free energy , , heat capacity ,Cv, and molecular structures of several species involving in keto↔enol tautomerism related to acetaldehyde (A), 5,5-dimethyl-1,3-cyclohexanedione (dimedone) and  acetylacetone (AA) h...

The i.r. spectra of iduronate residue-containing glycosaminolycans may provide clues about S-0-C bond environments B 1, 21. A conversion of the ionized iduronate residue carboxyl groups in heparin to the unionized, free acid form (i.e. a conversion of COOto COOH) resulted in the displacement of the absorption band assigned to iduronate residue C2 sulphate groups from about 800 cm-l to about 870...

Nucleic acids and proteins are two of the most important biomolecules in any living organism, with the former carrying genetic information and the latter executing and regulating the life processes. Protein–nucleic acid interactions therefore play a crucial role in central biological processes, ranging from the mechanism of replication, transcription and recombination to enzymatic events utiliz...

Despite the rapid advances which have occurred in structural biology and computational chemistry, the rational design of functional protein structures continues to be one of the most challenging objectives in the field of protein engineering involving synthetic model compounds and de novo peptides. The engineering of active sites is more complicated for metalloenzymes than for non-metalloenzyme...

three residues seems to be common to all the serine enzymes and has become known as the ‘charge-relay system’. Its function is to transfer a negative (or partial negative) charge from the aspartic acid residue to the oxygen atom of the hydroxy group of serine. This obviously increases the nucleophilicity of the serine, but the important point is that the charge is developed in the absence of bu...

Four polymorphs of 2-[methyl(phenyl)amino]nicotinic acid were discovered, and their single crystal structures were obtained at 90 K. In addition, one monohydrate and one salt were also crystallized and measured. Among the crystal structures, there are 17 crystallographically independent conformations. More interestingly, the four anhydrate forms are tessellated similarly by stacking of onedimen...

Protein misfolding and aggregation are now well-recognized processes that often lead to amyloid fibril formation (amyloidosis). Because these events are coupled with many types of human disease, the field of protein amyloidosis is under intense investigation. In the amyloid fibrils, the proteins adopt cross b-pleated sheet structures with distinct tinctorial and morphological properties, and ty...