50-69-1Relevant articles and documents
Thermal Behavior of d-Ribose Adsorbed on Silica: Effect of Inorganic Salt Coadsorption and Significance for Prebiotic Chemistry
Akouche, Mariame,Jaber, Maguy,Zins, Emilie-Laure,Maurel, Marie-Christine,Lambert, Jean-Francois,Georgelin, Thomas
, p. 15834 - 15846 (2016)
Understanding ribose reactivity is a crucial step in the “RNA world” scenario because this molecule is a component of all extant nucleotides that make up RNA. In solution, ribose is unstable and susceptible to thermal destruction. We examined how ribose behaves upon thermal activation when adsorbed on silica, either alone or with the coadsorption of inorganic salts (MgCl2, CaCl2, SrCl2, CuCl2, FeCl2, FeCl3, ZnCl2). A combination of13C NMR, in situ IR, and TGA analyses revealed a variety of phenomena. When adsorbed alone, ribose remains stable up to 150 °C, at which point ring opening is observed, together with minor oxidation to a lactone. All the metal salts studied showed specific interactions with ribose after dehydration, resulting in the formation of polydentate metal ion complexes. Anomeric equilibria were affected, generally favoring ribofuranoses. Zn2+stabilized ribose up to higher temperatures than bare silica (180 to 200 °C). Most other cations had an adverse effect on ribose stability, with ring opening already upon drying at 70 °C. In addition, alkaline earth cations catalyzed the dehydration of ribose to furfural and, to variable degrees, its further decarbonylation to furan. Transition-metal ions with open d-shells took part in redox reactions with ribose, either as reagents or as catalysts. These results allow the likelihood of prebiotic chemistry scenarios to be evaluated, and may also be of interest for the valorization of biomass-derived carbohydrates by heterogeneous catalysis.
Comprehensive investigation of the energetics of pyrimidine nucleoside formation in a model prebiotic reaction
Sheng, Yinghong,Bean, Heather D.,Mamajanov, Irena,Hud, Nicholas V.,Leszczynski, Jerzy
, p. 16088 - 16095 (2009)
The problem of β-nucleoside formation under prebiotic conditions represents one of the most significant challenges to the "RNA world" hypothesis. The possibility exists that alternative bases may have come before the contemporary bases (i.e., A, G, C, and
Biosynthesis of anti-HCV compounds using thermophilic microorganisms
Rivero, Cintia W.,De Benedetti, Eliana C.,Sambeth, Jorge E.,Lozano, Mario E.,Trelles, Jorge A.
, p. 6059 - 6062 (2012)
This work describes the application of thermophilic microorganisms for obtaining 6-halogenated purine nucleosides. Biosynthesis of 6-chloropurine- 2′-deoxyriboside and 6-chloropurine riboside was achieved by Geobacillus stearothermophilus CECT 43 with a conversion of 90% and 68%, respectively. Furthermore, the selected microorganism was satisfactorily stabilized by immobilization in an agarose matrix. This biocatalyst can be reused at least 70 times without significant loss of activity, obtaining 379 mg/L of 6-chloropurine-2′-deoxyriboside. The obtained compounds can be used as antiviral agents.
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Steiger
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Biochemical characterization of a recombinant acid phosphatase from Acinetobacter baumannii
Smiley-Moreno, Elizabeth,Smith, Douglas,Yu, Jieh-Juen,Cao, Phuong,Arulanandam, Bernard P.,Chambers, James P.
, (2021/06/09)
Genomic sequence analysis of Acinetobacter baumannii revealed the presence of a putative Acid Phosphatase (AcpA; EC 3.1.3.2). A plasmid construct was made, and recombinant protein (rAcpA) was expressed in E. coli. PAGE analysis (carried out under denaturing/ reducing conditions) of nickel-affinity purified protein revealed the presence of a nearhomogeneous band of approximately 37 kDa. The identity of the 37 kDa species was verified as rAcpA by proteomic analysis with a molecular mass of 34.6 kDa from the deduced sequence. The dependence of substrate hydrolysis on pH was broad with an optimum observed at 6.0. Kinetic analysis revealed relatively high affinity for PNPP (Km = 90 μM) with Vmax, kcat, and Kcat/Km values of 19.2 pmoles s-1, 4.80 s-1(calculated on the basis of 37 kDa), and 5.30 × 104 M-1s-1, respectively. Sensitivity to a variety of reagents, i.e., detergents, reducing, and chelating agents as well as classic acid phosphatase inhibitors was examined in addition to assessment of hydrolysis of a number of phosphorylated compounds. Removal of phosphate from different phosphorylated compounds is supportive of broad, i.e., 'nonspecific' substrate specificity; although, the enzyme appears to prefer phosphotyrosine and/or peptides containing phosphotyrosine in comparison to serine and threonine. Examination of the primary sequence indicated the absence of signature sequences characteristic of Type A, B, and C nonspecific bacterial acid phosphatases.
Hypoglycemic triterpenoid glycosides from Cyclocarya paliurus (Sweet Tea Tree)
Chen, Zuhui,Li, Jing,Lv, Wenyan,Sun, Huihui,Tan, Jie,Wang, Wenxuan,Wu, Jianping,Xu, Jialing,Xu, Kangping,Xuan, Tongyao,Yang, Zhichun,Ye, Zijun,Zhu, Hui,Zou, Zhenxing
, (2020/01/06)
Four new rarely occurred seco-dammarane triterpenoid glycosides (1–4) and four new dammarane triterpenoid glycosides (5–8), along with four known triterpenoids (9–12), were isolated from the 70% ethanol extract of the leaves of Cyclocarya paliurus (family Juglandaceae). Their structures were elucidated by extensive spectroscopic methods, including 1D/2D NMR and HRESIMS data, together with chemical analysis and DFT GIAO 13C NMR calculation. In bioassay, compounds 5–8 significantly increased glucose consumption in 3T3-L1 adipocytes, which could be the bioactive constituents for the anti-diabetes effect of the traditional usage of C. paliurus.