DTDP glucose oxidoreductase

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-... 

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],... 

The use of dTDP-6-deoxy-D-glucose-4- as a substrate for dTDP-D-glucose oxidoreductase (see p. 169) has permitted the stereochemistry of this normally closed system to be determined.169 The B side of NAD accepts the hydrogen atom. UDP-D-glucose 4-epimerase has also been shown168 to use this side of the NAD molecule. 

Proposed mechanism for the dTDP-n-glucose oxidoreductase reaction... 

Highly purified and crystalline dTDP-D-glucose oxidoreductase has now become available, and the presence of one mole of NAD per mole of enzyme has been established. That this NAD is reduced... 

Fig. 31. Formation of dTDP-rhamnose from dTDP-glucose 1 dTDP-D-Glucose oxidoreductase...

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