glucose 6- phosphate dehydrogenase from streptomyces aureofaciens was purified andinactivated by pyridoxal 5′-phosphate (plp). the inactivation was a pseudo-first order and time-dependentreaction. complete inactivation was achieved at 0.2mm plp within 16 minutes. the type of inhibition wascompetitive with respect to glucose 6- phosphate. spectral characteristics of plp-enzyme complexcorresponde...

interaction of glucose 6-phosphate dehydrogenase from s. aureofaciens with nad+, nadp+and glucose 6-phosphate were investigated using different fluorescent probes. binding of nad+, nadp+and s-nadph to the native enzyme quenched intrinsic protein fluorescence by 100%, 10% and 21%,respectively, from which kd values of nad+ (6.5 mm), nadp+ (92.0 μm) and s-nadph (122.0 μm)were calculated. binding o...

The title compound, (C(7)H(11)N(2))(3)[Nd(2)Cl(4)(H(2)O)(10)]Cl(5)·2H(2)O, consists of three 4-(dimethyl-amino)-pyridinium cations, one of which is disordered about an inversion center, one [Nd(2)Cl(4)(H(2)O)(10)](2+) dication possessing inversion symmetry, five chloride anions, one of which is disordered over two inversion centers, and two lattice water mol-ecules. The 4-(dimethyl-amino)-pyrid...

A detailed (1)H-NMR study of the anion binding properties of the 2-iodo-imidazolium receptor 1 in DMSO allows to fully attribute the observed affinities to strong charge-assisted C-I···X(-) halogen bonding (XB). Stronger binding was observed for oxoanions over halides. Phosphate, in particular, binds to 1 with an association constant of ca. 10(3) M(-1), which is particularly high for a single X...

Using in situ viscosity measurement, the rate of cellulose dissolution in a number of ionic liquids has been determined allowing their performance as solvents to be quantitatively assessed. 1-Butyl-3-methylimidazolium ethanoate was shown to dissolve cellulose faster than analogous ionic liquids with chloride or dimethylphosphate anions. Analysis of the data highlights the influence of both anio...

The potential mutagenicity of a zinc phosphate (Poscal), a polycarboxylate (Aqualox) and glass ionomer cements with (Argion) and without (Meron) silver reinforcement were characterized by employing the Ames Salmonella/microsome test. The materials were eluted in dimethyl sulphoxide or physiologic saline and the aliquots were used either immediately or after an incubation period of 24h at 37 deg...

Children up to 6 years of age who lived with pesticide applicators were monitored for increased risk of pesticide exposure: 48 pesticide applicator and 14 reference families were recruited from an agricultural region of Washington State in June 1995. A total of 160 spot urine samples were collected from 88 children, including repeated measures 3-7 days apart. Samples were assayed by gas chromat...

Methyl fluoride and dimethyl ether were previously identified as inhibitors of ammonia oxidation and N2O production in autotrophic nitrifying bacteria. We demonstrate that methyl fluoride and dimethyl ether are substrates for ammonia monooxygenase and are converted to formaldehyde and a mixture of methanol and formaldehyde, respectively.

The synthesis and binding investigations of first generation C(3v)-symmetrical hydrogen bonding urea-amide based tripodal receptors, 1-6, with various anions such as acetate, phosphate, sulfate and chloride in DMSO-d(6) are presented. Analysis of the (1)H NMR titrations of 1-6 showed on all occasions the selective formation of 1 : 1 stoichiometries.

Electronic circular dichroism (ECD) parameters of the disulphide chromophore have been calculated for dihydrogen disulphide, dimethyl disulphide, and cystine using density-functional theory, coupled-cluster theory, and multiconfigurational self-consistent field theory. The objective is twofold: first, to examine the performance of the Coulomb-attenuated CAM-B3LYP functional for the calculation ...