A novel iron-mediated direct C-H arylation of quinones and pyridine analogues with arylboronic acids has been developed using dichloromethane and water as solvents at ambient temperature. FeS is employed and serves as an efficient catalyst. A detailed reaction mechanism is speculated and expounded.

Experimental and theoretical studies together are providing insights into the mechanism by which proteins fold. Our present knowledge of the essential aspects of the folding reaction is outlined and some approaches, both theoretical and experimental, that are being developed to obtain a more detailed understanding of this complex process are described.

Dihydroorotase (DHO) is a zinc metalloenzyme that functions in the pathway for the biosynthesis of pyrimidine nucleotides by catalyzing the reversible interconversion of carbamoyl aspartate and dihydroorotate. A chemical mechanism was proposed on the basis of an analysis of the effects of pH, metal substitution, solvent isotope effects, mutant proteins, and alternative substrates on the enzyme-...

Upon treatment with carboxypeptidase, muscle aldolase (ketose-l-phosphate aldehyde-lyase, EC 4.1.2.7) loses 3 COOHterminal tyrosine residues (3, 4) and exhibits a 20-fold fall in the rate of fructose diphosphate cleavage (3) and a 500-fold fall in the rate of exchange detritiation of dihydroxyacetone phosphate (5). The cleavage of fructose-l-P is relatively unchanged (3). The present investigat...

In practical terms, the description of biomass pyrolysis kinetics by rationally-based models, that do not represent the detailed physicochemical mechanism of the process, but predict the overall yield, might be extremely useful. The mechanisms of global decomposition (by means an irreversible, single step, and first order reaction) have only been validated under dynamic regime at slow heating r...

Histidase catalyzes the irreversible nonoxidative deamination of histidine to urocanic acid. This reaction (Equation 1) has been studied in mammalian and bacterial preparations (1). Although enzymes which carry out similar deaminations of other amino acids (notably aspartic acid) have been described, to date no detailed studies of the mechanism of the process of nonoxidative deamination have be...

Cryptochrome (CRY) is a blue-light sensitive flavoprotein that functions as the primary circadian photoreceptor in Drosophila melanogaster. The mechanism by which it transmits the light signal to the core clock circuitry is not known. We conducted in vitro studies on the light-induced conformational change in CRY and its effect on protein-protein interaction and performed in vivo analysis of th...

Protein kinase activation, via autophosphorylation of the activation loop, is a common regulatory mechanism in phosphorylation-dependent signaling cascades. Despite the prevalence of this reaction and its importance in biological regulation, the molecular mechanisms of autophosphorylation are poorly understood. In this study, we developed a kinetic approach to distinguish quantitatively between...

This article firstly structures a detailed combustion reaction mechanism including methane N-butanol nitrogen oxide. According to two-stroke low-speed diesel engine’s parameter with the characteristics of engine firing, homogeneous charge compression ignition is selected as simulation model. At same output power and excess air coefficient 1.5, by means calculation analysis path mechanism, when ...