kinetics of tertiary alkyl ether synthesis

... previous report [14] Time course of dextran-independent glucan synthesis We examined the kinetics of insoluble glucan synthesis from sucrose by GS and GSGB in the absence of dextran (Fig 3A,B) For this ... kinetics of the acceptor reactions appeared to be similar between GS and GSGB Kinetic simulation of GTF glucan synthesis To explain the time course of saccharide production during the synthesis of ... the presence of increasing DP may be a common feature of glucansucrase Additional studies are required to elucidate the dextran-dependent synthesis of glucan As the affinity of the GBd of GTF-I for...

Ngày tải lên: 14/02/2014, 22:20

... GTP activation of the glutaminase reaction and CTP synthesis was compared (Fig 5) In the absence of GTP, the rate of glutamine hydrolysis was signicantly higher than the rate of CTP synthesis so ... CTP synthesis assay (A) GTP activation (squares) of CTP synthesis For comparison GTP activation of glutaminase activity in the presence of 0.1 mM (open circles) or mM (closed circles) each of ... GTP activation of the glutaminase activity in the presence of 0.1 mM (open circles) or mM (closed circles) each of UTP and ATP-cS (C) GTP activation of CTP synthesis at 0.1 mM each of UTP and ATP...

Ngày tải lên: 21/02/2014, 15:20

... ampicillin Values of 47 ± mM for KNapp and of 3.6 ± 0.22 for (Vs/Vh)max for the synthesis of ampicillin were obtained from fitting Eqn (8) to the data For synthesis of penicillin G, a value of 0.018 mM)1 ... reactive ester of NIPGB in kinetic experiments, failed because of the high rates of spontaneous hydrolysis of this compound The only substrate of PA for which the steady-state rate of hydrolysis ... analysis of penicillin acylase (Eur J Biochem 270) 3681 Fig Inhibition of NIPGB hydrolysis by 7-ADCA Lineweaver–Burk plot of the effect of various concentrations of 7-ADCA on the conversion of NIPGB...

Ngày tải lên: 08/03/2014, 08:20

... characteristics of [125I]TC-PCSK9 binding to HepG2 cells To determine whether the kinetics of binding of PCSK9 to HepG2 cells can be described as a simple bimolecular reaction, the kinetics of [125I]TC-PCSK9 ... [koff] of 0.0009 ± 0.00012 min)1 (n = 3), which corresponds to a half-time of dissociation of 770 Lowering the pH of dissociation medium to 6.2 also led to monophasic and slow dissociation of ... Mousavi et al Characterization of the binding of PCSK9 to intact cells levels of plasma LDL cholesterol, whereas loss -of- function mutations are associated with low levels of plasma LDL cholesterol...

Ngày tải lên: 14/02/2014, 14:20

... methodology to the study of the kinetics of catalysis by the serine protease a-CT we were able to statistically correlate the structurally dynamic behavior of the enzyme with its kinetics of catalysis From ... cutoff distance (rc ẳ 6.0 A) The dynamics of the resulting network are then dened by the Ni ã Nj Kirchhoff connectivity matrix of interresidue contacts (G) where the off diagonal elements of ... on the kinetics of enzymatic catalysis from both an experimental and theoretical perspective Changes in the kinetics of a-CT catalysis upon chemical glycosylation The catalytic behavior of a-CT...

Ngày tải lên: 19/02/2014, 05:20

... different species [23–25] The success of the series of studies shows that the stable framework structure of Fv enables the transfer of function by means of CDR replacement Barbas et al first designed ... Functionalization of small scaffold proteins by replacing a loop of the scaffold protein with a CDR loop of antibody fragments (A) Replacement of the candidate location in NCS for grafting with the CDR loop of ... grafting the CDR loop of the single variable heavy chain of a heavy-chain camel antibody (VHH) (Fig 1B) by comparing topologies between VHH and NCS (Fig 2A); grafting of the CDR loop of antilysozyme...

Ngày tải lên: 06/03/2014, 11:20

... concentrations of the non-physiological reductant dithiothreitol These data suggest that the DS-dependent inhibition of NAT1 is unlikely to be a result of the formation of a mixed disulfide, but rather of ... constant for the inhibition of NAT1 by DS (ki) was deduced from the slope of kobs as a function of the DS concentration [DS], and was · 104 m)1Æmin)1 The order of the reaction of DS with NAT1 (n) can ... identification and characterization of the molecular targets of DS are of prime importance in order to understand the pharmacological and ⁄ or toxicological effects of this therapeutic compound In...

Ngày tải lên: 07/03/2014, 02:20

... phosphinic acid derivatives of GSH as moderate Kinetics and inhibition of ATP-dependent ligases inhibitors of CfGspS [38] The most active of these was a phosphonic analogue of GSH (c-l-Glu-l-Leu-GlyP), ... (1997) Novel inhibitors of trypanothione biosynthesis: synthesis and evaluation of a phosphinate analog of glutathionyl spermidine (GSP), a potent, slow-binding inhibitor of GSP synthetase Bioorg ... the concentration of phosphinate and initiating with enzyme Modality of inhibition The mode of inhibition of the slow-binding phosphinate was determined by examining the effect of varying each...

Ngày tải lên: 07/03/2014, 04:20

... mutagenesis of Ser218 to Ala, as similar analysis of the mutated protein showed no evidence of phosphorylation [26] Residue S218 is detected by a variety of phosphorylation prediction software to ... Kd of SEPT2 is 0.28 lm and that of GDP is 1.7 lm in the presence of physiological Mg2+ concentrations These values are about an order of magnitude lower than those observed for complexes of yeast ... completion of most of the studies described herein Given the conserved nature of this residue we therefore mutated the residue back to arginine and found that none of the properties of the protein...

Ngày tải lên: 07/03/2014, 12:20

... elan-immunoreactive material Fig Evolution of rec-trappin-2 production by Pichia pastoris as a function of the duration of fermentation Aliquots of concentrated supernatants of rec-trappin-2-secreting P pastoris ... source of inhibitory elan Knowledge of the kinetic parameters characterizing a proteaseinhibitor interaction and of the in vivo concentration of an inhibitor is necessary to evaluate whether such ... Simon, S.R (2001) Kinetics of the Inhibition of Proteinase by Elan Am J Respir Cell Mol Biol 24, 8389 25 Bieth, J.G (1995) Theoretical and practical aspects of proteinase inhibition kinetics Methods...

Ngày tải lên: 07/03/2014, 15:20

... aggregates offers new possibilities in the investigation of the kinetic parameters and mechanism of violaxanthin de-epoxidation One of the advantages of such system is the defined orientation of violaxanthin ... [22] to analyse the kinetics of conversion of violaxanthin to zeaxanthin The model allowed us to follow independently the kinetics of the two de-epoxidation steps: the conversion of violaxanthin ... application of a mathematical model of de-epoxidation for the analysis of the obtained results provide important information on the influence of membrane physical properties, kinetic parameters of violaxanthin...

Ngày tải lên: 08/03/2014, 10:20

... Beta-ketoEsterFormationDuring the Sizingof Paperwith AlkylketeneDimers”, TappiJ., 70(4):135-139(1987) MARTON, J., “PracticalAspectsof Alkaline Sizingon Kinetics of Alkyl Ketene Dimer Reactions:Hydrolysis of Alkyl KeteneDime?, ... treatment of, or employment in the programs and activities which the Institute operates The Effects of Inorganic Salts and Precipitated Calcium Carbonate Filler on the Hydrolysis Kinetics of Alkylketene ... detrimentalmaterialson of the AKD hvdrolvsis kinetics have not been reported This paper focuses on the J d hydrolysis kinetics of AKD at different wet-end conditions, particularly at different concentrationsof salts...

Ngày tải lên: 09/03/2014, 01:20

... Reduction of FlRd by avorubredoxin reductase Spectral analysis of FlRd is complex due to the partial overlap of the optical contribution of its redox cofactors Figure shows the absorption spectrum of ... presence of an excess of NADH, two events can be deconvoluted: the reduction of [Fe-Cys4] (monitored at 560 nm) and the formation of semiquinone FMN (monitored at 390 nm after subtraction of the ... modeling of FlRd-reductase (not shown) suggest: (a) the presence of the residues competent to form H-bonds with the ribose 2Â-OH and 3Â-OH groups of NADH, and (b) the absence of a nest of positively...

Ngày tải lên: 16/03/2014, 11:20

... Length of Si nanowires using Au and Pt versus time at holding temperature of 1000 °C Fig Construction of log-scaled growth rate and reciprocals of growth Temperature for the determination of activation ... (c) HRTEM image of Si nanowire using Au (d) HRTEM image of Si nanowire using Pt Both were single crystal (e) EDS line mapping of Si nanowires using Au catalyst (f) EDS line mapping of Si nanowires ... is dependent on the type of catalyst This could be explained by the effect of the catalyst on the barrier energy to the nucleation of a new step at the growth front of the nanowires (i.e., the...

Ngày tải lên: 16/03/2014, 15:05

... Havsteen BH, Garcı´ a-Moreno M & Vazquez A (1992) Kinetics of a model of autocatalysis, coupling of a reaction in which the enzyme acts on one of its substrates J Theor Biol 154, 261–270 ´ ´ Varon ... irreversible step of pepsinogen activation Biochemistry 28, 2626–2630 33 Darvey IG (1977) Transient phase kinetics of enzyme reactions where more than one species of enzyme is present at the start of the ... a-Carmona F (2000) Kinetics of a self-amplifying substrate cycle: ADP-ATP cycling assay Biochem J 350, 237–243 36 Segel IH (1975) Kinetics of unireactant enzymes In Enzyme Kinetics (Segel IH,...

Ngày tải lên: 16/03/2014, 18:20

... amount of dopants in PANI_HCl_PTSA was calculated from the atomic S/N and Cl/N ratios This shows that the migration of HCl as a dopant is higher than that of PTSA because of the smaller size of the ... solution fine particles of solid PANI were precipitated slowly For the purpose of characterization of the precipitated poly- 2.4.7 X-ray diffraction (XRD) analysis The XRD analysis of the PANI film samples ... shear thinning of PANI_PTSA solution starts at a lower shear rate of 2.2 s− compared to PANI_HCl_PTSA, which undergoes shear thinning at a shear rate of 9.5 s− The initial viscosity of PANI_HCl_PTSA...

Ngày tải lên: 20/03/2014, 13:04

... as cofactor (C) Log kcat ⁄ Km with NADH as cofactor (D) Log kcat ⁄ Km with biliverdin as the variable substrate and NADH as cofactor 4420 cofactor, the kcat ⁄ Km data reveal two pK values of 5.1 ... the effect of pH on the kinetic parameters and site-directed mutagenesis studies, to gain an understanding of the function of sBVR-A in cyanobacteria and also to increase our knowledge of the mechanism ... saturating (10 lm) levels of biliverdin Initial rate data for nonsaturating levels of biliverdin show that bilirubin exhibits mixed inhibition kinetics at nonsaturating levels of biliverdin and, when...

Ngày tải lên: 23/03/2014, 05:22

... Time course of excision of 8-oxoGua (d), FapyGua (s) and FapyAde ( ) by OGG1 (B) Time course of excision of 8-oxoGua (d), FapyGua (s) and FapyAde ( ) by Fpg Means and standard deviations of three ... all plots Means of two independent experiments are shown [P], concentration of the AP product of this variant in vivo and contribute to the pathogenesis of Alzheimer’s disease Of all variants ... agreement with an earlier study of the activity and substrate specificity of OGG1-S326C [11], confirming the usefulness of this variant as a reference point for the kinetics of other OGG1 mutants Differences...

Ngày tải lên: 23/03/2014, 05:22

... presence of various metal concentrations and metal combinations was determined Figure shows the inactivation courses of apo-TNXI and of TNXI in the presence of mm concentrations of each of the ... studies of the mechanism of xylose isomerase Biochemistry 28, 7289–7297 Bradford MM (1976) A rapid and sensitive method for quantitation of microgram quantities of protein utilizing the principle of ... biophysical properties of some XIs have been studied in the presence of two different metals (e.g Mg2+ and Co2+) [43–45] For three of the enzymes studied here, the Tm in the presence of mm Mg2+ plus...

Ngày tải lên: 23/03/2014, 13:20

Ngày tải lên: 23/03/2014, 23:20