Glucose 6-phosphate, hydrolysis

Interestingly, however, the mechanisms of the two phosphate hydrolysis reactions in steps 9 and 11 are not the same. In step 9, water is the nucleophile, but in the glucose 6-phosphate reaction of step 11, a histidine residue on the enzyme attacks phosphorus, giving a phosphoryl enzyme intermediate that subsequently reacts with water. 

Nevertheless, the potential uses of these polymers are intriguing, especially since preliminary evidence has been obtained that hydrolysis to glucose, phosphate, and ammonia takes place slowly in aqueous media. Mixed-substituent glucosyl polymers appear to have the greatest biomedical potential since the use of a second, less hindered, side group allows the steric hindrance and deprotection problems to be minimized (37). 

Overbrowning of oat cakes brown discoloration of wheat bran Hydrolytic rancidity Hydrolytic rancidity Increase available phosphate Hydrolysis of phosphate compounds Detection of effectiveness of pasteurization Production of nucleotides and nucleosides Detection of effectiveness of blanching In combination with glucose oxidase... 

Hence, glycerol can be converted into pyruvate or glucose in the liver, which contains the appropriate enzymes. The reverse process can take place by the reduction of dihydroxyacetone phosphate to glycerol 3-phosphate. Hydrolysis by a phosphatase then gives glycerol. Thus, glycerol and glycolytic intermediates are readily interconvertible. 

The hydrolysis of glucose-6-su fate will proceed further to the right (higher and more negative AC) because the product, HSO, is a strong icid (pK,= 1.9) that spontaneously ionizes at pH 7 to SOj -l- H -. The product of glucose-6-phosphate hydrolysis. 

D-Glucosamine 6-phosphate is hydrolyzed by the D-glucose-6-phosphatase of rat-liver mitochondria. The rate of this hydrolysis is about 8 % of that of D-glucose 6-phosphate hydrolysis. A phosphatase which preferentially catalyzes the hydrolysis of D-glucosamine 6-phosphate has been prepared from Neurospora crassa. This enzyme is not stimulated by magnesium ions and has an optimum activity between pH 6 and 7.5. It appears to be distinct from acid, alkaline, and other specific phosphatases. 

Find K for (a) the hydrolysis of ATP, (b) the reaction of glucose with HP04" to form glucose phosphate, and (c) the coupled reaction between ATP and glucose, (d) How does each K change when Tchanges from 25°C to 37°C ... 

Triose, tetrose, and pentose phosphates enriched with C have been prepared by the Kiliani-Fischer reaction on the terminal phosphates of the next lower aldose. The mixed nitriles were separated on Dowex 1-X8 resin and reduced with hydrogen over Pd-BaS04. The synthesis of D-glucose 2-phosphate by phosphorylation of l,3,4,6-tetra-0-acetyl-j3-D-glucopyranosyl chloride, itself prepared by 2 1 acetyl migration, has been reported. Rates of phosphate hydrolysis in 0.25 M sulphuric acid and in 0.25 M sodium hydroxide were measured for D-glucose monophosphates in the former the order was 1-phosphate > 2-phosphate > 3-phosphate > 6-phosphate while in the latter it was 3-phosphate > 6-phosphate > 2-phosphate > 1-phosphate. ... 

The oligosaccharide was separated from the aglycone by acid hydrolysis and gel filtration and the yield of phosphate was measured. A composition was found of glucosamine mannose glucose phosphate of 2 11 1.5 2 mole ratios, which is close to other analyses of similar materials. The non-integral value for glucose would reflect incomplete glucosylation. 

The relative rates of hydrolysis of the glucose phosphate isomers have been given as l>2>3>6in0.25MH2SO4 3>6>2> 1 in0.25MNaOH... 

Since the ester is alkali-stable and non-reducing and liberates D-glucose on hydrolysis, the phosphate must be attached to carbon 1 in the D-glu-cose. Cori, Colowick, and Cori 218) suggested that the hexose phosphate... 

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