578-76-7Relevant articles and documents
Use of 13C as an indirect tag in 15N specifically labeled nucleosides. Syntheses of [8-13C-1,7,NH2-15N3]adenosine, -guanosine, and their deoxy analogues.
Shallop, Anthony J,Gaffney, Barbara L,Jones, Roger A
, p. 8657 - 8661 (2003)
We have previously reported the use of a 13C tag at the C2 of 15N-multilabeled purine nucleosides to distinguish the adjacent-labeled 15N atoms from those in an untagged nucleoside. We now introduce the use of an indirect tag at the C8 of 15N7-labeled purine nucleosides. This tag allows unambiguous differentiation between a pair of 15N7-labeled purines in which only one is 13C8 labeled. Although the very small C8-N7 coupling (200 Hz) because H8 is coupled to both N7 and C8. The 13C8 atom is introduced by means of a ring closure of the exocyclic amino groups of a pyrimidinone using [13C]sodium ethyl xanthate. Here, we present methods for the syntheses of [8-13C-1,7,NH2-15N3]adenosine, -guanosine, and their deoxy analogues.
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Lawley
, p. 586 (1968)
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Structural and biochemical characterization of the nucleoside hydrolase from C. elegans reveals the role of two active site cysteine residues in catalysis
Singh, Ranjan Kumar,Steyaert, Jan,Versées, Wim
, p. 985 - 996 (2017/05/01)
Nucleoside hydrolases (NHs) catalyze the hydrolysis of the N-glycoside bond in ribonucleosides and are found in all three domains of life. Although in parasitic protozoa a role in purine salvage has been well established, their precise function in bacteria and higher eukaryotes is still largely unknown. NHs have been classified into three homology groups based on the conservation of active site residues. While many structures are available of representatives of group I and II, structural information for group III NHs is lacking. Here, we report the first crystal structure of a purine-specific nucleoside hydrolase belonging to homology group III from the nematode Caenorhabditis elegans (CeNH) to 1.65? resolution. In contrast to dimeric purine-specific NHs from group II, CeNH is a homotetramer. A cysteine residue that characterizes group III NHs (Cys253) structurally aligns with the catalytic histidine and tryptophan residues of group I and group II enzymes, respectively. Moreover, a second cysteine (Cys42) points into the active site of CeNH. Substrate docking shows that both cysteine residues are appropriately positioned to interact with the purine ring. Site-directed mutagenesis and kinetic analysis proposes a catalytic role for both cysteines residues, with Cys253 playing the most prominent role in leaving group activation.
BODIPY-modified 2′-deoxyguanosine as a novel tool to detect DNA damages
Takamura-Enya, Takeji,Ishii, Ryoko
body text, p. 4206 - 4209 (2011/08/10)
BODIPY-modified 2′-deoxyguanosine was synthesized for use as a detection reagent for genotoxic compounds. BODIPY-FL is a well known fluorescence reagent whose fluorescent light emission diminishes near a guanine base by a photo-induced electron transfer process. We attached BODIPY-Fl to the 5′ position of the deoxyribose moiety of 2′-deoxyguanosine. Although this compound has low fluorescence activity, when depurination by the action of alkylating reagents and dG oxidation by singlet oxygen occurred, the emission of strong fluorescence was observed. BODIPY-dG was found, therefore, to be a very useful tool for selectively detecting DNA damaging activity particularly in natural environmental extracts.
