2-Keto-3-deoxy-gluconate

Gluconolactonase [Lactonase] (3.1.1.17) is present. Phospogluconate dehydratase (4.2.1.12) is present. Phospho-2-keto-3-deoxy-gluconate aldolase (4.1.2.14) is present. 

Additional information <1> (<1> no substrate 2-deoxy-D-ribose, 2-deoxy-D-glucose, o-gluconate, 2-keto-D-gluconate, 2-oxoglutarate, 2-oxo-3-deoxy-6-phosphogluconate [2]) [2]... 

Anderson, W.A. Magasanik, B. The pathway of myo-inositol degradation in Aerobacter aerogenes. Conversion of 2-deoxy-5-keto-D-gluconic acid to glycolytic intermediates. J. Biol. Chem., 246, 5662-5675 (1971)... 

The 2-keto-3-deoxy-aldonic acid (phosphate) aldolases from Pseudomonas strains - 3-deoxy-2-keto-L-arabonate (F.C 4.1.2.18), 3-deoxy-2-keto-D-xylonate (EC 4.1.2.28), 3-deoxy-2-keto-6-phospho-D-gluconate (EC 4.1.2.14) and 3-deoxy-2-keto-6-phospho-D-galactonate aldolase (EC 4.1.2.21) - appear to be specific even for the acceptor components, but allow stereoselective syntheses of the respective natural substrates29. 

Figure 10.11 Aldol reactions catalyzed in vivo by the 2-keto-3-deoxy-6-phospho-o-gluconate and 2-keto-3-deoxy-6-phospho-o-galactonate aldolases.

Phospho-2-keto-3-deoxygluconate aldolase, an enzyme in the Entner-Doudoroff pathway, that catalyzes the cleavage 6-phospho-2-keto-3-deoxy-D-gluconate to form pyruvate and D-glyceraldehyde 3-phosphate. 

This enzyme [EC 1.1.1.127], also known as 2-keto-3-deoxygluconate dehydrogenase, catalyzes the reaction of 2-dehydro-3-deoxy-D-gluconate with NAD to produce (4S)-4,6-dihydroxy-2,5-dioxohexanoate and NADH. The enzyme isolated from Pseudomonas can utilize NADP as the coenzyme whereas the enzymes isolated... 

The first such case was concerned with the limited substrate acceptance of d-2-keto-3-deoxy-6-phospho-gluconate (KDPG) aldolase (161). This catalyzes the (reversible) reaction of pyruvate (41) to certain chiral aldehydes such as 42, with formation of aldol products such as 43. It was known that this aldolase is highly specific for chir l-phosphorylated aldehydes with the d configuration at the C2 position leading stereoselectively to a precursor of the corresponding d sugar such as 44 (162) ... 

C. Auge and V. Delest, Microbiological aldolisations. Synthesis of 2-keto-3-deoxy-D-gluconate, Tetrahedron Asymm. 4 1165 (1993). 

R. Ramage, A. M. MacLeod, and G. W. Rose, Dioxolanes as synthetic intermediates. Part 6. Synthesis of 3-deoxy-D-manno-2-octulosonic acid (KDO), 3-deoxy-D-araMiio-2-heptulosonic acid (DAH) and 2-keto-3-deoxy-D-gluconic acid (KDG), Tetrahedron 47 5625 (1991). 

Keto-3-deoxy-6-phospho-D-gluconate Aldolase= 2-Keto-4-bydroxyglutarate Aldolase... 

The 2-keto-3-deoxy-6-phospho-D-gluconate (11) aldolase (KDPGlc aldolase or KdgA EC 4.1.2.14) provides the basis of the Entner-Doudoroff pathway that is used by many species of bacteria for the degradation of 6-phosphogluconate... 

Sharpless epoxidation was used to synthesize a key intermediate for the synthesis of 2-keto-3-deoxy-D-gluconic acid (KDG).1 Epoxide 1 was obtained in 80% yield and >90% ee (Eq. 6AA.1). 

D have an a-helix preceding the alft barrel this helix blocks the N-terminal end of the barrel fructose-biphosphate aldolase, 2-keto-3-deoxy-6-phospho- gluconate... 

Chain-extension reactions constitute a more widely used approach. Thus, the cyanohydrin synthesis followed by base-catalyzed cyclization and /1-elimination to iminolactones, which then undergo stepwise hydrolysis, affords 3-deoxy-2-glyculosonic acids.313 The overall yield of this reaction is low. Paerels314 used this method to prepare the first crystalline members of this group, namely 3-deoxy-D-m //iro-hex-2-ulosopyranosonic acid (2-keto-3-deoxy-D-gluconic acid, KDG, 119), and the L isomer, starting from D-ribose and L-arabinose, respectively. The synthesis of 119 is illustrated in Scheme 10. 

For organisms where the predominant pathway is the Entner-Doudoroff pathway, fructose-1,6-bis-P is not a major metabolite in glucose degradation (because glucose-6-P is converted first into 6-P-gluconate and then to 2-keto,3-deoxy,6-P-gluconate) the activators for their ADPGlc PPase are fructose-6-P and pyruvate (Preiss, 1969, 1984 Preiss and Romeo, 1989). 

Other pyruvate- and phosphoenolpyruvate-dependent aldolases have been isolated and purified, but have not yet been extensively investigated for synthetic use. Those showing promise for future applications include, 3-deoxy-D-arabino-2-heptulosonic acid 7-phosphate (DAHP) synthetase (EC 4.1.2.15), 2-keto-4-hydroxyglutarate (KHG) aldolase (EC 4.1.2.31), and 2-keto-3-deoxy-D-gluconate (KDG) aldolase (EC 4.1.2.20). DAHP synthetase has been used... 

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