Glycerone

Hexose diphosphate was found by Harden and Young69 in cell-free alcoholic-fermentation liquors. In 1930, it was observed that addition of fluoride to fermenting-yeast extracts leads to an accumulation of 0-phospho-D-glyceronic acid,60 which is also a metabolite of muscle extracts.61 Attention was turned, therefore, to the pathway from hexose diphosphate to 0-phos-pho-D-glyceronic acid. In 1932, Fischer and Baer62 described the synthesis of D-glycerose 3-phosphate, and, in 1933, Smythe and Gerischer63 noted... 

L-glyceronic acid. The formula XXXIV had also been proposed from the results of the application of the hydrazide rule28 to the hydrazide derivative of dihydrostreptosonic acid prepared by Folkers and coworkers.66... 

Fructose 1,6-bisphosphate is broken down by aldolase into the C3 compounds glyc-eraldehyde 3-phosphate (also known as glyc-eral 3-phosphate) and glycerone 3-phosphate (dihydroxyacetone 3-phosphate). 

By reduction from the glycolytic intermediate glycerone 3-phosphate (dihy-droxyacetone 3-phosphate enzyme glyc-erol-3-phosphate dehydrogenase (NAD+) l.l.l.S), or ... 

A special ketohexokinase [1] initially phos-phorylates fructose into fructose 1-phosphate. This is then cleaved by an aldolase [2], which is also fructose-specific, to yield glycerone 3-phosphate (dihydroxyacetone phosphate) and glyceraldehyde. Glycerone 3-phosphate is already an intermediate of glycolysis (center), while glyceraldehyde can be phosphorylated into glyceraldehyde 3-phosphate by triokinase [3]. 

Ribose 5-phosphate ) Xylulose 5-phosphate (1 Sedoheptulose 7-phosphate Glyceraldehyde 3-phosphate (1 Erythrose 4-phosphate Fructose 6-phosphate Fructose 1,6-bisphosphate Glycerone-3-phosphate... 

This enzyme [EC 2.3.1.42], also known as glycerone-phosphate O-acyltransferase, catalyzes the reaction of an acyl-CoA with dihydroxyacetone phosphate (or, glyc-erone phosphate) to produce coenzyme A and an acyldi-hydroxyacetone phosphate (or, an acylglycerone phosphate). The acyl-CoA derivatives of pahnitate, stearate, and oleate can all be utilized as substrates, with highest activity observed with palmitoyl-CoA. 

This enzyme [EC 4.1.2.17] catalyzes the aldol cleavage of L-fuculose 1-phosphate to yield glycerone phosphate and (5 )-lactaldehyde. 

This enzyme [EC 2.7.1.30], also known as glycerokinase and ATPiglycerol 3-phosphotransferase, catalyzes the reaction of ATP with glycerol to produce ADP and glycerol 3-phosphate. Both glycerone (or, dihydroxyacetone) and L-glyceraldehyde can serve as substrates. The nucleoside triphosphate can be substituted by UTP and, in the case of the yeast enzyme, ITP and GTP. 

Glycerol-3-phosphate dehydrogenase (NAD ) [EC 1.1.1.8] catalyzes the reaction of xn-glycerol 3-phosphate with NAD+ to produce glycerone phosphate (or, dihydroxyacetone phosphate) and NADH. 1,2-Propanediol phosphate and glycerone sulfate can also act as substrates, having a weaker affinity. 

This enzyme [EC 4.1.2.19] catalyzes the reversible conversion of L-rhamnulose 1-phosphate to dihydroxyace-tone phosphate (or, glycerone phosphate) and (5)-lactal-dehyde. 

This enzyme [EC 2.2.1.2], also known as dihydroxy acetone transferase and glycerone transferase, catalyzes the reversible reaction of sedoheptulose 7-phosphate with D-glyceraldehyde 3-phosphate to produce D-erythrose 4-phosphate and o-fructose 6-phosphate. 

This enzyme [EC 5.3.1.1], also known as triosephosphate mutase (TIM) and phosphotriose isomerase, catalyzes the interconversion of D-glyceraldehyde 3-phosphate and dihydroxyacetone phosphate (fUPAC glycerone phosphate). As pointed out by Rose, this enzyme is chiefly responsible for the largely symmetrical conversion of the two three-carbon segments of glucose to lactate and for the nearly uniform distribution of from pyruvate in the glucosyl units of hver glycogen. The... 

Oxoalkylarsonic acids lose arsenite by elimination, presumably after enolization, as described earlier (Section IV,B,2,c, and Fig. 9). In contrast, 3-oxoalkylphosphonic acids are stable e.g., the phosphono-methyl analogue of glycerone phosphate is a substrate for aldolase (118). The elimination of arsenite from 3-oxoalkylarsonic acids, but not of phosphite from 3-oxoalkylphosphonic acids, may reflect the fact that arsenite is relatively stable compared with arsenate, whereas phosphite is unstable compared with phosphate. 

S phosphoenolpyruvate -h glycerone <1> (<1> overall reaction of phosphotransferase system, involved in glycerol dissimilation of Escherichia coli... 

P histidine-containing protein -b glycerone phosphate <1> (<1> enzyme II complex [1]) [1]... 

P histidine-containing protein -I- dihydroxyacetone phosphate S phosphohistidinoprotein -I- glycerone <1> (<1> i.e. dihydroxyacetone, en-... 

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