Thymidine diphosphates

Figure 20-7. Summary of the interrelationships in metabolism of amino sugars. (At asterisk Analogous to UDPGIc.) Other purine or pyrimidine nucleotides may be similarly linked to sugars or amino sugars. Examples are thymidine diphosphate (TDP)-glucosamine and TDP-N-acetylglucosamine.

A mutant strain of Escherichia coli Y-10, defective in L-rhamnose synthesis, accumulates109 a considerable amount of thymidine diphosphate sugars. Three of them were identified110 as the esters of thymidine 5 -pyrophosphate with 6-deoxy-a-D-xyZo-hexopyranos-4-ulose (28), 6-deoxy-D-glucose, and D-fucose. The fourth component was found to be a 4-acetamido-4,6-dideoxy-D-galactose derivative111,112 (29) it occurs also in Pasteurella pseudotuberculosis102 and its... 

O. Gabriel and G. Ashwell, Biological mechanisms involved in the formation of deoxysugars. I. Preparation of thymidine diphosphate glucose labelled specifically in carbon 3, J. Biol. Chem., 240 (1965) 4123-4127. 

Nakano, Y., Suzuki, N., Yoshida, Y., Nezu, T., Yamashita, Y., Koga, T. Thymidine diphosphate-6-deoxy-l-lyxo-4-hexulose reductase synthesizing dTDP-6-deoxy-l-talose from Actinobacillus actinomycetemcomitans. J Biol Chem 275 (2000) 6806-6812. 

Thymine Deoxyribose Thymidine Thymidylic acid thymidine monophosphate (dTMP) Thymidine diphosphate (dTDP) Thymidine triphosphate (dTTP)... 

Borch reported the synthesis of thymidine diphosphate glucose (107) via a new method that employs a highly reactive zwitterionic phosphoramidate intermediate as the phosphorylating species (Scheme 2). This methodology was also used... 

In order to develop a purification procedure of thymidine 5 -diphosphate-glucose-4,6-dehydratase based on affinity chromatography, novel activated thymidine diphosphate analogues that display high affinity for the dehydratase have been synthesised. These diphosphate analogues have been derived from... 

The methyl group attached to the 5-OH arises by transfer of the methyl of S-adenosylmethionine catalyzed by a specific 0-methyltransferase [21]. A specific 5-ketoreductase has been shown to convert 5-keto avermectins into the B components [22]. The glycosyltransferase which catalyzes the stepwise transfer of oleandrose from thymidine diphosphate oleandrose to the aglycone has been demonstrated in cell free extracts [23]. Whether the sugars are transferred sequentially is not clear. 

C. Thymidine diphosphate-X dTDP-hexoses D-glucose, D-mannose,... 

A number of conjugated deoxyribonucleoside diphosphates are known, although those knoum are less numerous than similar compounds of the ribose series. For example, dCDP-choline and dCDP-ethanolamine have been found in sea urchin eggs and in animal tissues, but their significance is unknown. Various thymidine diphosphate sugars (see Table l-I) have been isolated from bacterial cells these compounds ser e as coenzymes in the synthesis of polysaccharides in Salmonella typhimurium. 

Marumo K, Lindquist L. Verma N. Weintraub A, Reeves P, Lindbetg AA. Enzymatic synthesis and isolation of thymidine dipho phate-6-slcoxY D Xy(o-4 hexulose and thymidine diphosphate-L-ihamnose. Eur J Biochem 1992 204 539-545. 

Matsuhashy M, Strominger JL. Thymidine diphosphate 4-acetamido 4,6 dideoxyhcxoses. 1. Enzymatic synthesis by straiits of Eschencfiiaeob. J Biol Chem 1966 239 2454-2463. 

Thymidine cyclic 3, 5 -(methylphosphate), C-165 Thymidine diphosphate, T-105 Thymidine 3, 5 -diphosphate, T-106 Thymidine 3 -phosphaie, T-107 Thymidine 5 -phosphate, T-108... 

Leloir-GTs utilize sugar nucleotides as activated donor substrates. Sugar moieties bound to nucleoside mono- or diphosphates, like cytosine monophosphate (CMP), thymidine diphosphate (dTDP), guanosine diphosphate (GDP), and the most common uridine diphosphate (UDP), are transferred by two types of Leloir-GTs. 

D., Uou, K.-K., Lee, H.-C., Sohng, J.-K. et al. (2010) One-pot enzymatic synthesis of deoxy-thymidine-diphosphate (TDP)-2-deoxy-a-d-glucose using phos-phomannomutase. J. Mol. Catal. E ... 

The a,p-imido analogue (116) of thymidine diphosphate has been prepared i 9 and 5 -0-(a-thio)tilphosphates of some 2, 3 -dideojgmucleosides have been synthesized. A cyclic dimer of FDU monophosphate has been shown to have in vivo antitumour activity as does FDU itself, and with less toxicity. 

Fig. 14. Effect of 5-fluorouracil (5-FU) and 5-fluorodeoxyuridine (5-FdUMP) on the synthesis of RNA and DNA. 5-FU is incorporated into RNA whereas 5-FdUMP inhibits thymidilate synthetase competitively and blocks DNA synthesis. The conversion of thymidine (dTr) into thymidilate (dTMP) by means of thymidine kinase is only a subsidary routine to thymidilate which can become important, however, under certain conditions such as in developing pollen (page 185). U = uridine triphosphate, Tr = thymidine, TMP = thymidine monophosphate = thymidilate, TDP = thymidine diphosphate, TTP = thymidine triphosphate, 5-F = 5-fluoro, d = deoxy, 1 = thymidine kinase, 2 = thymidilate synthetase.

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