246 resultados para communication and information technology
Studies of the association and contribution of lysosomal proteases towards mitochondrial proteolysis
Resumo:
A naturally occurring inhibitor of serine hydroxymethyltransferase (EC2.1.2.1) in mung bean seedlings extracts was purified by ammonium sulphate precipitation, phenyl-Sepharose chromatography followed by heating to release the inhibitor bound to the protein. The inhibitor had an absorption maximum at 200 nm, was not precipitated by trichloroacetic acid, was dialysable and resistant to inactivation by heating at 98-degrees-C for 4 hr, protease and ribonuclease digestion; but was acid labile. The chromatographically pure preparation inhibited both mung bean and sheep liver SHMT. Qualitative and quantitative analyses indicated that it contained a carbohydrate moiety, an O-amino and vicinal diol groups. Paper electrophoresis at pH 4.3 suggested that the inhibitor was positively charged.
Resumo:
Low temperature fluorination with elemental fluorine of elemental phosphorus, sulphur, silicon, amorphous carbon and phosphorus trichloride, phosphorus pentoxide, triphenylphosphine, hexafluorodisilane, hexachlorodisilane, hexabromodisilane, tetrasulphur tetranitride, sulphur dioxide, thionyl chloride and sulphuryl chloride has been carried out in freon-11 medium. The corresponding fluoro compounds have been isolated in near quantitative yields, purified by low temperature fractional condensation and characterised by IR spectroscopy and elemental analysis.
Resumo:
Novel one and two dimensional NMR techniques are proposed and utilized for the determination of the signs of the order parameters used for the study of the mobility of the fatty acid chains. The experiments designed to extract this information involve the use of the intensities of the side bands in the spectra of oriented systems spinning at the magic angle. Advantages of the two dimensional technique over the one dimensional method are discussed. The utility of the method in the study of the dynamic properties of membranes and model systems is pointed out.
Resumo:
A new method of construction of carbon-carbon bond is described. Thus the dianions generated from the metal-ammonia reduction of substituted benzoic acids readily undergo Michael addition with methyl crotonate resulting in synthetically useful products having a quaternary carbon. Based on this strategy, new syntheses of (+/-)-methyl acorate (14b) and (+/-)-methyl epi-corate (15) are reported.