Factor IXa (FIXa) is known to have a binding site for heparin that has not been mapped by a mutagenesis study. By homology modeling based on structural data, we identified eight basic residues in the catalytic domain of FIXa that can potentially bind to heparin. These residues, Lys(98), Lys(126), Arg(165), Arg(170), Lys(173), Lys(230), Arg(233), and Lys(239) (chymotrypsin numbering) were substi...

Enzymes in Uracil DNA glycosylase (UDG) superfamily are essential for the removal of uracil. Family 4 UDGa is a robust uracil DNA glycosylase that only acts on double-stranded and single-stranded uracil-containing DNA. Based on mutational, kinetic and modeling analyses, a catalytic mechanism involving leaving group stabilization by H155 in motif 2 and water coordination by N89 in motif 3 is pro...

Most studies neglect the presence of thermal cracking reactions in industrial FCC process. Nevertheless, the present work proposes a new model which modified the 10-lumps kinetic model given by Jacob el al. (1976), through to inclusion a new lump named dry gas represent the results of the thermal reactions. Similarly as in the 10-lumps kinetic model, the proposed 11-lumps kinetic model consider...

the potential of bulk starter fermentation strategy for production of a cost-effective and safe source of β-galactosidase was investigated. three different bulk starter media with different compositions were selected, and an industrial yogurt starter culture strain, l. bulgaricus dsm 20081 was cultivated in these media under ph-controlled conditions (ph=5.6) at 43°c. the media consisted of 1) b...

thermodynamic restrictions and simultaneous effects of operational conditions on the homogeneous rhodium-catalyzed carbonylation of methanol are studied in this line of research. it is shown that the general nrtl-virial model can be appropriated to study thermodynamics of the carbonylation. it is obtained that the reaction is kinetically and thermodynamically reasonable at temperatures above 42...

Kinetic modeling using nonlinear differential equations is proposed to analyze the spontaneous generation of enantiomeric excess in the autocatalytic addition of diisopropylzinc to prochiral pyrimidine carbaldehydes (Soai reaction). Our approach reproduces experimentally observed giant chiral amplification from an initial enantiomeric excess of <10(-6)% to >60%, high sensitivity and positive re...

Electron transfer within rat neuronal nitric-oxide synthase (nNOS) was investigated by pulse radiolysis. Radiolytically generated 1-methyl-3-carbamoyl pyridinium (MCP) radical was found to react predominantly with the heme of the enzyme with a second-order rate constant for heme reduction of 3 x 10(8) m(-1) s(-1). In the calmodulin (CaM)-bound enzyme a subsequent first-order phase was observed ...

Physicochemical patterns of complex reduction multicomponent charge have been studied in the absence liquid phases order to obtain spongy ligatures. The contained both simple oxides and oxide compounds. was conducted being realized at expense carbon gases (CO H2) as well with participation carbide phase, which formed during process. dependence phase composition products on initial ratios O/(C+H...

Ni/Al-HMS/HZSM-5 catalysts with varying amounts of Si/Al ratios were prepared via the impregnation method and evaluated for the hydrogenation of benzene at 130−190 °C. To study the catalyst characterization, various methods were used as X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, temperature-programmed des...

Pyrolysis is an applicable method that has been widely used to recover hydrocarbons from Used Lubricating Oil (ULO). However, large-scale application of this approach has been limited by its noticeably energy and time consuming nature. In the present research, it has been attempted to modify the energy and time requirements of ULO pyrolysis using the catalytic effects of metal oxide nanoparticl...