66224-66-6Relevant articles and documents
Meteorite-catalyzed intermoleculartrans-glycosylation produces nucleosides under proton beam irradiation
Bizzarri, Bruno Mattia,Fanelli, Angelica,Kapralov, Michail,Krasavin, Eugene,Saladino, Raffaele
, p. 19258 - 19264 (2021/06/03)
Di-glycosylated adenines act as glycosyl donors in the intermoleculartrans-glycosylation of pyrimidine nucleobases under proton beam irradiation conditions. Formamide and chondrite meteorite NWA 1465 increased the yield and the selectivity of the reaction
One-Step Synthesis of 2-Fluoroadenine Using Hydrogen Fluoride Pyridine in a Continuous Flow Operation
Salehi Marzijarani, Nastaran,Snead, David R.,McMullen, Jonathan P.,Lévesque, Fran?ois,Weisel, Mark,Varsolona, Richard J.,Lam, Yu-Hong,Liu, Zhijian,Naber, John R.
supporting information, p. 1522 - 1528 (2019/07/10)
We report the development of a one-pot synthesis of 2-fluoroadenine from an inexpensive 2,6-diaminopurine starting material using diazonium chemistry in a continuous fashion. Given the sensitivity of this transformation to temperature, we conducted critical experiments to study the exothermicity of the reaction and the heat removal, which were critical for the development of the process. Our goal was to improve the yield and purity of this pharmaceutical intermediate (2-fluoroadenine) and develop a more robust process.
Silica Metal Oxide Vesicles Catalyze Comprehensive Prebiotic Chemistry
Mattia Bizzarri, Bruno,Botta, Lorenzo,Pérez-Valverde, Maritza Iveth,Saladino, Raffaele,Di Mauro, Ernesto,García-Ruiz, Juan Manuel
, p. 8126 - 8132 (2018/05/29)
It has recently been demonstrated that mineral self-assembled structures catalyzing prebiotic chemical reactions may form in natural waters derived from serpentinization, a geological process widespread in the early stages of Earth-like planets. We have s
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.
The Chemoenzymatic Synthesis of 2-Chloro- and 2-Fluorocordycepins
Denisova, Alexandra O.,Tokunova, Yulia A.,Fateev, Ilja V.,Breslav, Alexandra A.,Leonov, Vladimir N.,Dorofeeva, Elena V.,Lutonina, Olga I.,Muzyka, Inessa S.,Esipov, Roman S.,Kayushin, Alexey L.,Konstantinova, Irina D.,Miroshnikov, Anatoly I.,Stepchenko, Vladimir A.,Mikhailopulo, Igor A.
, p. 4853 - 4860 (2017/10/06)
Two approaches to the chemoenzymatic synthesis of 2-fluorocordycepin and 2-chlorocordycepin were studied: (i) the use of 3′-deoxyadenosine (cordycepin) and 3′-deoxyinosine (3′dIno) as donors of 3-deoxy- d -ribofuranose in the transglycosylation of 2-fluoro- (2F Ade) and 2-chloroadenine (2Cl Ade) catalyzed by the recombinant E. coli purine nucleoside phosphorylase (PNP), and (ii) the use of 2-fluoroadenosine and 3′-deoxyinosine as substrates of the cross-glycosylation and PNP as a biocatalyst. An efficient method for 3′-deoxyinosine synthesis starting from inosine was developed. However, the very poor solubility of 2Cl Ade and 2F Ade is the limiting factor of the first approach. The second approach enables this problem to be overcome and it appears to be advantageous over the former approach from the viewpoint of practical synthesis of the title nucleosides. The 3-deoxy-α- d -ribofuranose-1-phosphate intermediary formed in the 3′dIno phosphorolysis by PNP was found to be the weak and marginal substrate of E. coli thymidine (TP) and uridine (UP) phosphorylases, respectively. Finally, one-pot cascade transformation of 3-deoxy- d -ribose in cordycepin in the presence of adenine and E. coli ribokinase, phosphopentomutase, and PNP was tested and cordycepin formation in ca. 3.4% yield was proved.
A Global Scale Scenario for Prebiotic Chemistry: Silica-Based Self-Assembled Mineral Structures and Formamide
Saladino, Raffaele,Botta, Giorgia,Bizzarri, Bruno Mattia,Di Mauro, Ernesto,Garcia Ruiz, Juan Manuel
, p. 2806 - 2811 (2016/06/01)
The pathway from simple abiotically made organic compounds to the molecular bricks of life, as we know it, is unknown. The most efficient geological abiotic route to organic compounds results from the aqueous dissolution of olivine, a reaction known as serpentinization (Sleep, N.H., et al. (2004) Proc. Natl. Acad. Sci. USA 101, 12818-12822). In addition to molecular hydrogen and a reducing environment, serpentinization reactions lead to high-pH alkaline brines that can become easily enriched in silica. Under these chemical conditions, the formation of self-assembled nanocrystalline mineral composites, namely silica/carbonate biomorphs and metal silicate hydrate (MSH) tubular membranes (silica gardens), is unavoidable (Kellermeier, M., et al. In Methods in Enzymology, Research Methods in Biomineralization Science (De Yoreo, J., Ed.) Vol. 532, pp 225-256, Academic Press, Burlington, MA). The osmotically driven membranous structures have remarkable catalytic properties that could be operating in the reducing organic-rich chemical pot in which they form. Among one-carbon compounds, formamide (NH2CHO) has been shown to trigger the formation of complex prebiotic molecules under mineral-driven catalytic conditions (Saladino, R., et al. (2001) Biorganic & Medicinal Chemistry, 9, 1249-1253), proton irradiation (Saladino, R., et al. (2015) Proc. Natl. Acad. Sci. USA, 112, 2746-2755), and laser-induced dielectric breakdown (Ferus, M., et al. (2015) Proc Natl Acad Sci USA, 112, 657-662). Here, we show that MSH membranes are catalysts for the condensation of NH2CHO, yielding prebiotically relevant compounds, including carboxylic acids, amino acids, and nucleobases. Membranes formed by the reaction of alkaline (pH 12) sodium silicate solutions with MgSO4 and Fe2(SO4)3·9H2O show the highest efficiency, while reactions with CuCl2·2H2O, ZnCl2, FeCl2·4H2O, and MnCl2·4H2O showed lower reactivities. The collections of compounds forming inside and outside the tubular membrane are clearly specific, demonstrating that the mineral self-assembled membranes at the same time create space compartmentalization and selective catalysis of the synthesis of relevant compounds. Rather than requiring odd local conditions, the prebiotic organic chemistry scenario for the origin of life appears to be common at a universal scale and, most probably, earlier than ever thought for our planet.
Continuous fluorescence assays for reactions involving adenine
Firestone, Ross,Cameron, Scott,Tyler, Peter,Ducati, Rodrigo,Spitz, Adam,Schramm, Vern
, p. 11860 - 11867 (2018/04/25)
5′-Methylthioadenosine phosphorylase (MTAP) and 5′-methylthioadenosine nucleosidase (MTAN) catalyze the phosphorolysis and hydrolysis of 5′-methylthioadenosine (MTA), respectively. Both enzymes have low KM values for their substrates. Kinetic assays for these enzymes are challenging, as the ultraviolet absorbance spectra for reactant MTA and product adenine are similar. We report a new assay using 2-amino-5′-methylthioadenosine (2AMTA) as an alternative substrate for MTAP and MTAN enzymes. Hydrolysis or phosphorolysis of 2AMTA forms 2,6-diaminopurine, a fluorescent and easily quantitated product. We kinetically characterize 2AMTA with human MTAP, bacterial MTANs and use 2,6-diaminopurine as a fluorescent substrate for yeast adenine phosphoribosyltransferase. 2AMTA was used as the substrate to kinetically characterize the dissociation constants for three-transition-state analogue inhibitors of MTAP and MTAN. Kinetic values obtained from continuous fluorescent assays with MTA were in good agreement with previously measured literature values, but gave smaller experimental errors. Chemical synthesis from ribose and 2,6-dichloropurine provided crystalline 2AMTA as the oxalate salt. Chemo-enzymatic synthesis from ribose and 2,6-diaminopurine produced 2-amino-S-adenosylmethionine for hydrolytic conversion to 2AMTA. Interaction of 2AMTA with human MTAP was also characterized by pre-steady-state kinetics and by analysis of the crystal structure in a complex with sulfate as a catalytically inert analogue of phosphate. This assay is suitable for inhibitor screening by detection of fluorescent product, for quantitative analysis of hits by rapid and accurate measurement of inhibition constants in continuous assays, and pre-steady-state kinetic analysis of the target enzymes.
Interaction between isoamyl adenine and rice cytokinin oxidase
Fang, Yujiao,Li, Yong,Liang, Xiaosheng,Xiao, Qian,Wu, Yunhua
, p. 362 - 366 (2016/07/06)
Cytokinin (CTK) dehydrogenase is responsible for regulating the endogenous CTK content by oxidative removal of the side chain. Herein, we have applied fluorescence method to study the interaction between CTK dehydrogenase and CTK in vitro and obtain some parameters of their interaction. We found that addition of isopentenyl adenine can quench the fluorescence of CTK dehydrogenase, and the quenching mechanism was to be a static quenching procedure. We have measured the number of binding sites n and the apparent binding constant K and have calculated the thermodynamics parameter ΔH, ΔG, and ΔS by fluorescence quenching method. Based on thermodynamics parameter’s results, we concluded that their binding reaction was both entropy driven and the enthalpy driven, and the Van der Waals force and hydrogen bond force played a major role in the interaction. Based on the synchronous fluorescence spectrometry results, we demonstrated that the binding site between isopentenyl adenine and CTK dehydrogenase is in the microenvironment of both tryptophan and tyrosine. The fluorescence signal of coenzyme, flavin adenine dinucleotide, decreases gradually with the addition of isopentenyl adenine. And this method can be used for isopentenyl adenine routine assay. Under optimized experimental parameters, the linear segment increases from 0.6?μM to 100?μM with a regression equation of ΔF?=?0.04?+?0.15cip (r?=?0.999, cip in μM) with the detection limit of 0.15?μM iP.
Multimodal Vacuum-Assisted Plasma Ion (VaPI) Source with Transmission Mode and Laser Ablation Sampling Capabilities
Keelor, Joel D.,Farnsworth, Paul B.,L. Weber, Arthur,Abbott-Lyon, Heather,Fernández, Facundo M.
, p. 897 - 907 (2016/05/02)
We have developed a multimodal ion source design that can be configured on the fly for various analysis modes, designed for more efficient and reproducible sampling at the mass spectrometer atmospheric pressure (AP) interface in a number of different applications. This vacuum-assisted plasma ionization (VaPI) source features interchangeable transmission mode and laser ablation sampling geometries. Operating in both AC and DC power regimes with similar results, the ion source was optimized for parameters including helium flow rate and gas temperature using transmission mode to analyze volatile standards and drug tablets. Using laser ablation, matrix effects were studied, and the source was used to monitor the products of model prebiotic synthetic reactions. [Figure not available: see fulltext.]
Characterization of inosine-uridine nucleoside hydrolase (RihC) from Escherichia coli
Arivett, Brock,Farone, Mary,Masiragani, Ranjith,Burden, Andrew,Judge, Shelby,Osinloye, Adedoyin,Minici, Claudia,Degano, Massimo,Robinson, Matthew,Kline, Paul
, p. 656 - 662 (2014/03/21)
A non-specific nucleoside hydrolase from Escherichia coli (RihC) has been cloned, overexpressed, and purified to greater than 95% homogeneity. Size exclusion chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis show that the protein exists as a homodimer. The enzyme showed significant activity against the standard ribonucleosides with uridine, xanthosine, and inosine having the greatest activity. The Michaelis constants were relatively constant for uridine, cytidine, inosine, adenosine, xanthosine, and ribothymidine at approximately 480 μM. No activity was exhibited against 2′-OH and 3′-OH deoxynucleosides. Nucleosides in which additional groups have been added to the exocyclic N6 amino group also exhibited no activity. Nucleosides lacking the 5′-OH group or with the 2′-OH group in the arabino configuration exhibited greatly reduced activity. Purine nucleosides and pyrimidine nucleosides in which the N7 or N3 nitrogens respectively were replaced with carbon also had no activity.
