Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Cytidine diphosphate 2 -deoxy

Cytarabine is a pyrimidine nucleoside related to idoxuridine (43). It is used primarily as an anticancer rather than an antiviral agent. Cytarabine acts by blocking the utilization of deoxycytidine, thereby inhibiting the repiication of viral DNA. The drug is first converted to mono-, di-, and triphosphates, which interfere with DNA synthesis by inhibiting both DNA polymerase and the reductase that promotes the conversion of cytidine diphosphate into its deoxy derivatives. [Pg.1877]

The de novo pathway to 2 -deoxythymidine monophosphate (dTMP) synthesis first requires the use of dUMP (2 -deoxyuridine-5 -monophosphate) from the metabolism of either UDP or CDP (cytidine diphosphate). The hydrolysis of dUTP (2 -deoxyuridine-5 -triphosphate) to dUMP and subsequent methylation at C-5 by the action of thymidylate synthase, using A, A i°-methylenetetrahydrofolate (THF) as the methyl donor, generate dTMP (Figure 6.54). The latter is subsequently phosphorylated to deoxy-thymidine triphosphate (dTTP) used in DNA synthesis and repair. [Pg.597]

DeoxyribOM phosphates phosphorylated derivatives of the deoxypentose, l-deoxy-n-rihose. They are biosynthesized by reduction of ribose phosphates in the course of nucleotide synthesis There are two enzymes in E. coli which reduce cytidine diphosphate to deoxycytidine diphosphate. Deoxytibose 5- and 1-phosphate form an equilibrium mixture in the presence of phosphopentomutase (EC 2.7.5.6). [Pg.168]

L-fucose, D-rhamnose GDP-D-mannuronic acid GDP-4-keto-6-deoxy-D-mannose P, P -Diguanosine tetraphosphate P, P -Diguanosine triphosphate Guanosine tetraphosphate Cytidine diphosphate-X CDP-D-glucose CDP-L-ribitol... [Pg.12]

Rubenstein PA, Strpminget jL. Enzymatic synthesis of cytidine diphosphate 3,6-dideoxyheX OSes. Vll. Mechanistic roles of enzyme El and pyridoxamine S -phosphate in the formation of cytidine diphosphace 4-kecO 3,6 dideoxy D-glucose from cytidine diphoisphate-4 keiO 6-deoxy-D-glucose. J Biol Chem 1974 249 3776-3781. [Pg.728]

Scheme 14.11. A proposal for the use of ribonucleoside diphosphate reductase (ribonucleotide diphosphate reductase, EC 1.17.4.1) to convert adenosine diphosphate (ADP), uridine diphosphate (UDP), and cytidine diphosphate (CDP) into their respective 2 -deoxy analogues deoxyadenosine diphosphate (dADP),deoxyuridine diphosphate (dUDP),and deoxy-cytidine diphosphate (dCDP), or, in general, ribonucleic acids (RNAs) into the corresponding deoxyribonucleic acids (DNAs) (after Stubbe, J. 7. Biol. Chem., 1990,265, 5330). Scheme 14.11. A proposal for the use of ribonucleoside diphosphate reductase (ribonucleotide diphosphate reductase, EC 1.17.4.1) to convert adenosine diphosphate (ADP), uridine diphosphate (UDP), and cytidine diphosphate (CDP) into their respective 2 -deoxy analogues deoxyadenosine diphosphate (dADP),deoxyuridine diphosphate (dUDP),and deoxy-cytidine diphosphate (dCDP), or, in general, ribonucleic acids (RNAs) into the corresponding deoxyribonucleic acids (DNAs) (after Stubbe, J. 7. Biol. Chem., 1990,265, 5330).
Figure 9.4 Monoterpene biosynthesis in peppermint oil gland secretory cells. The enzymes involved in this pathway are (1) 1-deoxy-D-xylulose 5-phosphate synthase, (2) 2-C-methyl-D-erythritol 4-phosphate reductoisomerase, (3) 2-C-methyl-D-erythritol 4-phosphate cytidyltransferase, (4) 4-(cytidine 5 -diphospho)-2-C-methyl-D-erythritol kinase, (5) 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase, (6) isopentenyl diphosphate isomerase, (7) geranyl diphosphate synthase, (8)... Figure 9.4 Monoterpene biosynthesis in peppermint oil gland secretory cells. The enzymes involved in this pathway are (1) 1-deoxy-D-xylulose 5-phosphate synthase, (2) 2-C-methyl-D-erythritol 4-phosphate reductoisomerase, (3) 2-C-methyl-D-erythritol 4-phosphate cytidyltransferase, (4) 4-(cytidine 5 -diphospho)-2-C-methyl-D-erythritol kinase, (5) 2-C-methyl-D-erythritol 2,4-cyclodiphosphate synthase, (6) isopentenyl diphosphate isomerase, (7) geranyl diphosphate synthase, (8)...
Thus, uridine-cytidine kinase converts uridine and cytidine to UMP and CMP, respectively thymidine kinase converts thymidine to dTMP and adenosine kinase converts adenosine to AMP. Specific kinases convert monophospho-nucleotides to dinucleotides using ATP as a phosphate donor. The conversion of diphosphonucleotides to triphosphonucleotides is carried out by a nonspecific nucleoside diphosphate kinase. This includes both the ribo- and deoxy-ribonucleotides. Cytosine and its nucleoside and nucleotide transformations are often associated with the metabolism of uracil and its nucleosides and nucleotides. Note that UTP can give rise to CTP (Figure 10.9), and also that, in the presence of cytidine deaminase, cytidine can be converted to uridine. [Pg.278]

Closely related to ATP, and present in biological systems, are a number of other nucleoside triphosphates and their corresponding diphosphates and monophosphates. These are uridine triphosphate (UTP), cytidine triphosphate (CTP), guanosine triphosphate (GTP), and thymidine triphosphate (TTP), all of which have about the same free energy of hydrolysis as ATP (11.29). In addition there are the deoxy nucleoside triphosphates (Chapter 10.4). [Pg.943]

Cytidine phosphates cytidine S -monophosphate (CMP, cytidylic acid, M, 323.2), cytidine 5 -diphos-phate (CDP, M, 403.19) and cytidine 5 -triphosphate (CTP, M, 483.16). For structure, see e. g. Pyrimidine biosynthesis. CTP is a precursor of RNA synthesis, while deoxy-CTP is a precursor of DNA synthesis. CDP may be regarded as the coenzyme of phospholipid biosynthesis (see Membrane lipids) (activated choline is CDP-choline). Glycerol and the sugar alcohol, ribitol, are also activated by bonding to CDP (see Nucleoside diphosphate sugars). Reduction of ribose... [Pg.150]

Reaction of e. coli ribonucleotide reductase with ( )-2 -fluoro-methylene-2 -deoxy-cytidine 5 -diphosphate... [Pg.41]

The biosynthesis of thymine and cytosine (the former as thymidine and the latter as cytidine as they bear 5 -phosphorylated carbohydrate units) utilize uracil (as uridine diphosphate [UDP]). Further, of course, since for thymidine the 2 -deoxy-sugar must form first, the carbohydrate reduction must also be considered. [Pg.1331]

Figure 12 Evidence for an enhanced stability of the Cd as well as the Ca ", Mg, and Co " 1 1 complexes (eq. 2) of ADP ( ), IDP ((g)), and GDP " (O), based on the relationship between log M(R-DP) P H(R-DP) simple M(R-DP) complexes (O), where R-DP = phenyl diphosphate (PhDP ), methyl diphosphate (MeDP ), uridine 5 -diphosphate (UDP ), cytidine 5 -diphosphate (CDP ), thymidine [= l-(2-deoxy-P-D-ribofuranosyl)thymine] 5 -diphosphate (dTDP ), and z-butyl diphosphate (BuDP ) (from left to right). The least-squares lines (eq. 15) are drawn through the indicated six data sets taken from ref. [115]. The points due to the M /NDP systems are based on the values listed in Table 10. The vertical broken lines emphasize the stability differences from the reference lines they equal log m/ndp as defined in analogy to equation (14) (see also Table 10, column 4). All the plotted equilibrium constants refer to aqueous solutions at 25°C and / = 0.1 M (NaNOg). Figure 12 Evidence for an enhanced stability of the Cd as well as the Ca ", Mg, and Co " 1 1 complexes (eq. 2) of ADP ( ), IDP ((g)), and GDP " (O), based on the relationship between log M(R-DP) P H(R-DP) simple M(R-DP) complexes (O), where R-DP = phenyl diphosphate (PhDP ), methyl diphosphate (MeDP ), uridine 5 -diphosphate (UDP ), cytidine 5 -diphosphate (CDP ), thymidine [= l-(2-deoxy-P-D-ribofuranosyl)thymine] 5 -diphosphate (dTDP ), and z-butyl diphosphate (BuDP ) (from left to right). The least-squares lines (eq. 15) are drawn through the indicated six data sets taken from ref. [115]. The points due to the M /NDP systems are based on the values listed in Table 10. The vertical broken lines emphasize the stability differences from the reference lines they equal log m/ndp as defined in analogy to equation (14) (see also Table 10, column 4). All the plotted equilibrium constants refer to aqueous solutions at 25°C and / = 0.1 M (NaNOg).
The flavoenzyme from Yersinia pseudotuberculosis (YerD) catalyzes in vivo the acyloin condensation of pyruvate to the ketone, cytidine-5 -diphosphate-3,6-di(deoxy)-4-keto-D-glucose [52]. Investigations on its synthetic capabilities revealed that this enzyme can catalyze aldehyde-ketone cross-acyloin condensations, furnishing tertiary alcohols (Table 10.6) [52], Small cyclic aliphatic ketone derivatives, for example, cydohexanone and methylated cyclohexanones, tetrahydro-2H-pyran-3-one (Table 10.6), open-chain ketones containing an ether moiety, diketones, and ketones containing an - or p-ketoesters were aU successfully converted [52],... [Pg.296]

YerE was found to be even more promising. It is an enzyme involved in the biosynthetic pathway of Yersinose A, a branched-chain 3,6-di(deoxy)hexose. It catalyzes the ThDP-dependent coupling of pymvate with cytidine-5 -diphosphate-3,6-di(deoxy)-4-keto-D-glucose. The amino-acid sequence of YerE was found to be very similar to the large subunit of Escherichia coli AHAS (EcAHAS). Furthermore, as for AHAS, YerE was found to suppress the formation of acetolactate in favor of (/ )-PAC. The scope of this new... [Pg.838]


See other pages where Cytidine diphosphate 2 -deoxy is mentioned: [Pg.132]    [Pg.747]    [Pg.747]    [Pg.190]    [Pg.87]    [Pg.88]    [Pg.244]    [Pg.245]    [Pg.266]    [Pg.85]    [Pg.145]    [Pg.294]    [Pg.35]    [Pg.348]    [Pg.124]    [Pg.239]    [Pg.180]    [Pg.2698]    [Pg.147]    [Pg.2]   
See also in sourсe #XX -- [ Pg.99 ]




SEARCH



Cytidine

Cytidine 2-deoxy-5 -methyl-, 3,5-diphosphate

© 2024 chempedia.info