Glucose 6-phosphate, preparation

The preparation of these solutions is described in the text in section 4.6.7.2. Pipette these successively into 1-cm cuvettes. The absorbance of the mixtures is read twice (at 340 nm) before (ODi) and after (OD2) the addition of glucose-phosphate isomerase. G6P-DH glucose-6-phosphate dehydrogenase, HK hexokinase, NADP nicotinamide adenine dinucleotide, PGI glucose phosphate isomerase, TEA triethanolamine... 

We have developed preparative enzymatic syntheses of several unusual hexoketoses using fructose-1,6-diphosphate aldolase (FDP-aldolase, E.C.4.1.2.13) as catalyst and dihydroxyacetone phosphate (DHAP) and an aldehyde as substrates (15). The enzyme appears to be very specific for DHAP but will accept a variety of aldehydes as acceptors. The ketose-1-phosphates prepared are converted to the phosphate free ketoses after removal of the phosphate group by acid- or phosphatase-catalyzed hydrolysis. The ketoses can be isomerized stereospecifically to aldoses catalyzed by glucose isomerase (E.C.5.3.1.5.) from Flavobacteriuum arborescens. The equilibrium mixtures of aldoses and ketoses are then separated by chromatography on Dowex 50 (Ba ) or Dowex 1 (HSO "). Figure 1 illustrates the preparation of a mixture of 6-deoxy-6-fluoro-D-fructose... 

D-Glucose 2-phosphate is formed as decomposition product of uridine diphosphate glucose with cyclic 1,2-glucose phosphate as intermediate . It has been prepared by phosphorylation of r,3,4,6-tetraacetyl-/ D-glucose with diphenyl phosphorochloridate . 

Among the few biochemical preparations of 0 -labeled compounds is the preparation of glucose-phosphate (Cohn, 1949) and of ATP (Cohn, 1953). The quantities of water required are usually too large to make biochemical preparations worthwhile. 

Phosphate Esters. The phosphorylation of sucrose using sodium metaphosphate has been reported (78). Lyoptulization of a sodium metaphosphate solution of sucrose at pH 5 for 20 hours followed by storage at 80°C for five days produced a mixture of sucrose monophosphates. These products were isolated by preparative hplc, with a calculated yield of 27% based on all organic phosphate as sucrose monoesters. Small proportions of glucose and fmctose were also formed. 

Deoxy-D-jcylo hexose 6-(dihydrogen phosphate) (21) has also been synthesized (2) the reaction sequence makes use of 3-deoxy l 2,5 6-di-O-isopropylidene D-galactofuranose (16), a compound that can be easily prepared from D-glucose (2, 60). The mono-isopropylidene derivative (17) formed by partial hydrolysis of the di-ketal is converted into the 6-tosylate (18) by reaction with one molar equivalent of p-toluenesulfonyl chloride. From this the epoxide (19) is formed by reaction with sodium methoxide. Treatment of the anhydro sugar with an aqueous solution of disodium hydrogen phosphate (26) leads to the 6-phosphate (20)... 

The vicinal diol groups of deoxy sugar phosphates can be cleaved by periodate in the usual conditions without affecting the stability of the phosphate group, so that this reaction can be used for preparative purposes in certain cases. Thus, if 3-deoxy glucose 6-phosphate (23) is... 

A seed culture of S. cerevisiae ATCC 24860 (American Type Culture Collection, Manassas, VA, USA) was grown in a media of 5g glucose, and 0.5 g yeast extract, respectively, 1.5 g KH2P04 and 2.25 g Na2P04 phosphate buffer up to a total volume of distilled water, 500 ml. The media was sterilised at 121 °C for 15 min. The stock culture of the microorganisms was transferred to the broth media for preparation of seed culture. 

The most convenient method is the formation of two equivalents of (25) by retro-aldol cleavage from commercially available (26) by the combined action of FruA and triose phosphate isomerase (Figure 10.18 inset) [84]. This scheme has been extended into a highly integrated, artificial metabolism for the efficacious in situ preparation of (25) from inexpensive feedstock such as glucose and fructose (two equivalents of... 

Varagic, V. M. and Zugic, M., Interactions of xanthine derivatives, catecholamines, and glucose-6-phosphate on the isolated phrenic nerve diaphragm preparation of the rat, Pharmacology, 5, 275, 1971. 

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