DTDP glucose

Recently, some knowledge was acquired concerning nature s approach to the synthesis of dideoxy sugars. 6-Deoxygenation of glucose seems to follow a redox pathway via the nucleotide glucoside dTDP-glucose with oxidoreductase which leads to a 6-deoxy-4-uloside [1],... 

A higher space-time yield (98 versus 59 g 1, 1 d ) was reached in an EMR than in a batch reactor for the synthesis of dTDP-glucose and by-product D-fructose from sucrose and dTDP (Elling, 1995). 

El-Kazzaz, W., Morita, T., Tagami, H., Inada, T., Aiba, H. Metabolic block at early stages of the glycolytic pathway activates the Res phosphorelay system via increased synthesis of dTDP-glucose in Escherichia coli. Mol Microbiol 51 (2004) 1117-1128. 

As already shown for the 3- and 2-deoxysugars, a NDP-4-keto-6-deoxyglucose 5 is assumed to be a precursor (Scheme 7) of o-desosamine and has been proven indirectly to be the precursor of 4,6-dideoxyhexose moiety of spectinomycin (15) [41], since stereochemical analysis showed that the configuration of the b -CHj group in 15 is inverted when fed with stereo chemically labeled 6R)- and (6S)-[6- C,4- H, 6- H]glucose. This inversion at C-6 points to the involvement of a dTDP-glucose oxidoreductase (see Sect. 2.1.1., Scheme 2). Since the 4,6-di-... 

Scheme 48. Substrate specificity of dTDP-glucose-4,6-deydratase...

Ma Y, Stern RJ, Scherman MS, Vissa VD, Yan W, Jones VC, Zhang F, Franzblau SG, Lewis WH, Mcneil MR. Drug targeting Mycobacterium tuberculosis cell wall synthesis genetics of dTDP-rhamnose synthetic enzymes and development of a microtiter plate-based screen for inhibitors of conversion of dTDP-glucose to dTDP-rhamnose. Antimicrob. Agents Chemother. 2001 1407-1416. 

Fig. 4 Reaction mechanism of dTDP-glucose 4,6-dehydratase as proposed by Allard et al. [125], The first half of the reaction involves abstraction of a proton from the 4 hydroxyl group, and hydride transfer from C-4 to NAD. In the next step, a proton is removed from the C-5 atom of the sugar, and the C-6 hydroxyl group is protonated and eliminated as water. This yields the 4-keto-5,6-ene intermediate. The product is obtained after hydride transfer from NADH to carbon atom C-6 and protonation of carbon atom C-5...

Use of the enzyme dTDP-glucose-4,6-dehydratase on the substrate dTDP-glucose has generated the corresponding 6-deoxy-4-keto product - but it partly isomerized to the 3-keto compound during workup. 3-Azido-3-deoxy- and 3-deoxy-dTDP-glucose were also substrates affording the 3-modified 6-deoxy-4-keto products. ... 

Gross, J.W., Hegeman, A.D., Vestling, M.M., Frey, RA. (2000) Characterization of Enzymatic Processes by Rapid Mix-quench Mass Spectrometry The Case of dTDP-Glucose 4,6-Dehydratase. Biochemistry 39 13633-13640. 

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