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Fructose-1,6-biphosphate reaction catalyzed

A typical chemical system is the oxidative decarboxylation of malonic acid catalyzed by cerium ions and bromine, the so-called Zhabotinsky reaction this reaction in a given domain leads to the evolution of sustained oscillations and chemical waves. Furthermore, these states have been observed in a number of enzyme systems. The simplest case is the reaction catalyzed by the enzyme peroxidase. The reaction kinetics display either steady states, bistability, or oscillations. A more complex system is the ubiquitous process of glycolysis catalyzed by a sequence of coordinated enzyme reactions. In a given domain the process readily exhibits continuous oscillations of chemical concentrations and fluxes, which can be recorded by spectroscopic and electrometric techniques. The source of the periodicity is the enzyme phosphofructokinase, which catalyzes the phosphorylation of fructose-6-phosphate by ATP, resulting in the formation of fructose-1,6 biphosphate and ADP. The overall activity of the octameric enzyme is described by an allosteric model with fructose-6-phosphate, ATP, and AMP as controlling ligands. [Pg.30]

Recently, a chemoenzimatic catalized Henry reaction has been reported by El Blidi et al.53 Nitroaldol cyclization between the masked 3-hydroxy-4-nitrobutyraldehyde 72 and dihydroxyacetone phosphate (DHAP) 73, catalyzed by fructose-1,6-biphosphate aldolase (RAMA), afforded the nitro-cyclohexane 74 (Scheme 24). [Pg.181]

Fructose 1,6-biphosphate aldolase from rabbit muscle in nature reversibly catalyzes the addition of dihydroxyacetone phosphate (DHAP) to D-glyceraldehyde 3-phosphate. The tolerance of this DHAP-dependent enzyme towards various aldehyde acceptors made it a versatile tool in the synthesis of monosaccharides and sugar analogs [188], but also of alkaloids [189] and other natural products. For example, the enzyme-mediated aldol reaction of DHAP and an aldehyde is a key step in the total synthesis of the microbial elicitor (—)-syringolide 2 (Fig. 35a) [190]. [Pg.29]

FBP aldolases) catalyzing the coupling of DHAP with Ga3P 35 to form fructose-1,6-biphosphate 55 (Scheme 28.23). These enzymes do not require any co-factor and can be used in a straightforward reaction in aqueous buffered solutions, with a tolerance for certain organic solvents (DMSO/DMF) that can be thus used as co-solvents to obtain a better solubility of the substrates. Some immobilized catalysts were also obtained in view to increase the efficiency of the reaction notably toward selectivity. [Pg.843]


See other pages where Fructose-1,6-biphosphate reaction catalyzed is mentioned: [Pg.49]    [Pg.55]   
See also in sourсe #XX -- [ Pg.270 ]




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Fructose-1,6-biphosphate

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