Dihydroxyacetone phosphate aldolases

Aldol reactions catalyzed in vivo by the four stereo-complementarydihydroxyacetone phosphate-dependent aldolases. 

Natural glycolytic substrates of fructose 1,6-bisphosphate aldolases. 

The DHAP aldolases are quite specific for the phosphorylated nucleophile 41, tvhich must therefore be prepared independently or generated in situ (cf. Section 5.4.4). Initial aldol products tvill thus contain a phosphate ester moiety, vhich facilitates product isolation, for example by barium salt precipitation or by use of ion-exchange techniques. The corresponding phosphate free compounds can be easily obtained by mild enzymatic hydrolysis using an inexpensive alkaline phosphatase at pH 8-9 [148], vhereas base-labile compounds might require vorking at pH 5-6 using a more expensive acid phosphatase [149]. 

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The hexose phosphate, fructose-1,6-diphosphate, is split by aldolase into two triose phosphates glyceraldehyde-3-phosphate and dihydroxyacetone phosphate. Aldolase consists of four 40-kDa subunits. Three tissue-specific forms exist in human tissues aldolase A (ubiquitous and very active in the muscle), aldolase B (liver, kidney, and small intestine), and aldolase C (specific to the brain). These three isozymes have nearly the same molecular size but differ in substrate specificity,... 

Aldehyde, 1-Phosphorylated dihydroxyacetone 2-keto-3,4-diol phosphate Synthesis of polyhydroxylated 2-ketones Dihydroxyacetone phosphate aldolase... 

Dihydroxyacetone phosphate aldolases and threonine aldolases generate two asymetric centers. The former type has been explored extensively and many synthetic examples exist (Figure 1.19). 

J. Calveras, M. Egido-Gabas, L. G6mez, I. Casas, T. Parella, I. loglar, I. Bujons, P. Clap, Dihydroxyacetone phosphate aldolase-catalyzed synthesis of structurally diverse polyhy-droxylated pyrrolidine derivatives and evaluation of their glycosidase inhibitory properties, Chem. Eur. J. 15 (2009) 7310-7328. 

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