Phytoene desaturase (PDS) is an essential plant carotenoid biosynthetic enzyme and a prominent target of certain inhibitors, such as norflurazon, acting as bleaching herbicides. PDS catalyzes the introduction of two double bonds into 15-cis-phytoene, yielding 9,15,9'-tri-cis-ζ-carotene via the intermediate 9,15-di-cis-phytofluene. We present the necessary data to scrutinize functional implicati...

Human catechol-O-methyltransferase (COMT, EC 2.1.1.6) catalyzes the transfer of the methyl group to a variety of endogenous and exogenous catechol substrates using S-adenosyl-L-methionine as the methyl donor. This enzymatic O-methylation plays an important role in the inactivation of biologically-active and toxic catechols. A number of studies in recent years have sought to characterize the pol...

In this work the kinetic data demanded for kinetic modeling were obtained in temperatures 350, 400, 450 and 500 oC by conducting experimentations on a Fe-Cr nanocatalyst prepared from a novel method and a commercial Fe-Cr-Cu one. The collected data were subjected to kinetic modeling by using two models derived from redox and associative mechanisms as well as an empirical one. The coefficients o...

A potentially general kinetic method for the investigation of active-site availability in preparations of macromolecular catalysts was developed. Three kinetic models were considered: (a) the conventional two-step model of enzyme catalysis, where the preparation contains only active catalyst (E(a)) and inert (i.e. non-binding, non-catalytic) material (E(i)); (b) an extension of the conventional...

In this study, a new strategy in catalytic ozonation removal method for degradation of phenol from industrial wastewater was investigated. Magnetic carbon nano composite as a novel catalyst was synthesized, characterized and then used in the catalytic ozonation process (COP) and compared with the single ozonation process (SOP). The influential parameters were all investigated. The results showe...

• Fe©SiO 2 speeds up the auto-catalytic cycle in non-oxidative coupling of methane. Addition C hydrocarbons has same effect as catalyst. CH 4 conversion gas-phase is fast after induction. Product selectivity essentially determined by reactions. The experimentally observed interplay between catalytic activation methane on and free radical under conditions analyzed mechanistic modeling well exper...

hot spots are among the most serious operational issues in furnaces as they may result in the destruction of tubes. hence, it is essential to locate such hot spots precisely on the tube surfaces inside the industrial furnaces in order to secure a safe design and operation. in the current study, we have extended the model proposed by talmor in order to precisely locate the combustion hot spots o...

NO synthase (NOS) enzymes convert L-arginine to NO in two sequential reactions whose rates (k(cat1) and k(cat2)) are both limited by the rate of ferric heme reduction (k(r)). An enzyme ferric heme-NO complex forms as an immediate product complex and then undergoes either dissociation (at a rate that we denote as k(d)) to release NO in a productive manner, or reduction (k(r)) to form a ferrous h...