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1.
Whi-Gun Chae 《Biotechnology and Bioprocess Engineering》1999,4(1):17-20
Facile synthetic methods of 2′,5′-dideoxy-, 2′,3′-dideoxy- and 3′-deoxy-1,N
6-ethenoadenosine nucleosides by either an enzymatic dideoxyribosyl transfer reaction or a simple chemical reaction were proposed.
The synthetic products were isolated and purified by preparative HPLC and their structures were confirmed by1H NMR (500 MHz) and FAB-MS including high resolution mass measurement. These modified nucleoside analogs have not been reported
yet. Therefore, these modified nucleoside analogs are of potential value to be studied further for biological activity such
as anticancer or antiviral. 相似文献
2.
M. F. Kasakin T. V. Abramova V. N. Silnikov 《Russian Journal of Bioorganic Chemistry》2011,37(6):752-757
A simple and efficient method has been developed for the preparation of 2′-aminomethylmorpholino-4′-carboxymethyl nucleoside
analogues and their 2′-N-Boc-modified derivatives as synthons for obtaining oligomers by peptide synthesis methods. 相似文献
3.
A. D. Malakhov E. V. Malakhova S. V. Kuznitsova I. V. Grechishnikova I. A. Prokhorenko M. V. Skorobogatyi V. A. Korshun Yu. A. Berlin 《Russian Journal of Bioorganic Chemistry》2000,26(1):34-44
Novel reagents for the fluorescent labeling of oligo- and polynucleotides have been prepared: 5-(1-pyrenylethynyl)-2′-deoxyuridine
3′-phosphoramidite and a solid support carrying this nucleoside. Oligo-nucleotides containing one or several modified units
have been synthesized, and the fluorescence of these probes has been shown to change upon hybridization with the complementary
sequence.
Fluorescent Nucleosides. III. The previous communications, see [1, 2]. Prefix “d” in the oligodeoxynucleotide designations
is omitted. 相似文献
4.
Arvind Misra Pratibha Dwivedi Mohammad Shahid 《Russian Journal of Bioorganic Chemistry》2009,35(1):62-67
A modified fluorescent probe UFAA AAT CTC CGC CGC was synthesized using the nucleoside analogue 3′-O-(N,N′-diisopropylamino-2-cyanoethoxyphosphinyl)-5′-O-(4,4′-dimethoxytrityl)-2′-O-(dansyl-1-sulfonamidohexylaminocarbonyl)uridine for hybridization studies with perfectly matched (U/A) complementary DNA
and with a DNA strand having similar G-rich telomeric units at their 3′-ends. Data on the thermal stability and decrease in
fluorescence intensity due to the presence of dG units clearly demonstrated the potential application of this approach in
DNA diagnostics in homogeneous hybridization assays.
The text was submitted by the authors in English. 相似文献
5.
Horinouchi N Ogawa J Kawano T Sakai T Saito K Matsumoto S Sasaki M Mikami Y Shimizu S 《Applied microbiology and biotechnology》2006,71(5):615-621
2′-Deoxyribonucleosides are important as building blocks for the synthesis of antisense drugs, antiviral nucleosides, and 2′-deoxyribonucleotides for polymerase chain reaction. The microbial production of 2′-deoxyribonucleosides from simple materials, glucose, acetaldehyde, and a nucleobase, through the reverse reactions of 2′-deoxyribonucleoside degradation and the glycolytic pathway, was investigated. The glycolytic pathway of baker’s yeast yielded fructose 1,6-diphosphate from glucose using the energy of adenosine 5′-triphosphate generated from adenosine 5′-monophosphate through alcoholic fermentation with the yeast. Fructose 1,6-diphosphate was further transformed to 2-deoxyribose 5-phosphate in the presence of acetaldehyde by deoxyriboaldolase-expressing Escherichia coli cells via d-glyceraldehyde 3-phosphate. E. coli transformants expressing phosphopentomutase and nucleoside phosphorylase produced 2′-deoxyribonucleosides from 2-deoxyribose 5-phosphate and a nucleobase via 2-deoxyribose 1-phosphate through the reverse reactions of 2′-deoxyribonucleoside degradation. Coupling of the glycolytic pathway and deoxyriboaldolase-catalyzing reaction efficiently supplied 2-deoxyribose 5-phosphate, which is a key intermediate for 2′-deoxyribonucleoside synthesis. 2′-Deoxyinosine (9.9 mM) was produced from glucose, acetaldehyde, and adenine through three-step reactions via fructose 1,6-diphosphate and then 2-deoxyribose 5-phosphate, the molar yield as to glucose being 17.8%. 相似文献
6.
Cytosolic 5′ nucleotidase II (cN-II) catalyses both the hydrolysis of a number of nucleoside monophosphates (e.g., IMP + H2O→ inosine + Pi), and the phosphate transfer from a nucleoside monophosphate donor to the 5′ position of a nucleoside acceptor (e.g., IMP + guanosine → inosine + GMP). The enzyme protein functions through the formation of a covalent phosphoenzyme intermediate, followed by the phosphate transfer either to water (phosphatase activity) or to a nucleoside (phosphotransferase activity). It has been proposed that cN-II regulates the intracellular concentration of IMP and GMP and the production of uric acid. The enzyme might also have a potential therapeutic importance, since it can phosphorylate some anti-tumoral and antiviral nucleoside analogues that are not substrates of known kinases. In this review we summarise our recent studies on the structure, regulation and function of cN-II. Via a site-directed mutagenesis approach, we have identified the amino acids involved in the catalytic mechanism and proposed a structural model of the active site. A series of in vitro studies suggests that cN-II might contribute to the regulation of 5-phosphoribosyl-1-pyrophosphate (PRPP) level, through the so-called oxypurine cycle, and in the production of intracellular adenosine, formed by ATP degradation. 相似文献
7.
Horinouchi N Ogawa J Kawano T Sakai T Saito K Matsumoto S Sasaki M Mikami Y Shimizu S 《Biotechnology letters》2006,28(12):877-881
A one-pot enzymatic synthesis of 2′-deoxyribonucleoside from glucose, acetaldehyde, and a nucleobase was established. Glycolysis by baker’s yeast (Saccharomyces cerevisiae) generated ATP which was used to produce d-glyceraldehyde 3-phosphate production from glucose via fructose 1,6-diphosphate. The d-glyceraldehyde 3-phosphate produced was transformed to 2′-deoxyribonucleoside via 2-deoxyribose 5-phosphate and then 2-deoxyribose 1-phosphate in the presence of acetaldehyde and a nucleobase by deoxyriboaldolase, phosphopentomutase expressed in Escherichia coli, and a commercial nucleoside phosphorylase. About 33 mM 2′-deoxyinosine was produced from 600 mM glucose, 333 mM acetaldehyde and 100 mM adenine in 24 h. 2′-Deoxyinosine was produced from adenine due to the adenosine deaminase activity of E. coli transformants. 相似文献
8.
Kunhorm Phongsakorn Chueaphromsri Phongsakorn Chaicharoenaudomrung Nipha Noisa Parinya 《Biotechnology letters》2022,44(4):581-593
Biotechnology Letters - Cordycepin (3′-deoxyadenosine) is a nucleoside analogue and biosynthesised by Cordyceps militaris, an entomopathogenic fungus. In this study, an epigenetic modifier... 相似文献
9.
S.-y. Xu J.-p. Xiao L. Ettwiller M. Holden J. Aliotta C. L. Poh M. Dalton D. P. Robinson T. R. Petronzio L. Moran M. Ganatra J. Ware B. Slatko J. Benner 《Molecular & general genetics : MGG》1998,260(2-3):226-231
The genes encoding the ApaLI (5′-G^TGCAC-3′), NspI (5′-RCATG^Y-3′), NspHI (5′-RCATG^Y-3′), SacI (5′-GAGCT^C-3′), SapI (5′-GCTCTTCN1^-3′, 5′-^N4GAAGAGC-3′) and ScaI (5′-AGT^ACT-3′) restriction-modification systems have been cloned in E.␣coli. Amino acid sequence comparison of M.ApaLI, M.NspI, M.NspHI, and M.SacI with known methylases indicated that they contain the ten conserved motifs characteristic of C5 cytosine methylases. NspI and NspHI restriction-modification systems are highly homologous in amino acid sequence. The C-termini of the NspI and NlaIII (5′-CATG-3′) restriction endonucleases share significant similarity. 5mC modification of the internal C in a SacI site renders it resistant to SacI digestion. External 5mC modification of a SacI site has no effect on SacI digestion. N4mC modification of the second base in the sequence 5′-GCTCTTC-3′ blocks SapI digestion. N4mC modification of the other cytosines in the SapI site does not affect SapI digestion. N4mC modification of ScaI site blocks ScaI digetion. A DNA invertase homolog was found adjacent to the ApaLI restriction-modification system. A DNA transposase subunit homolog was found upstream of the SapI restriction endonuclease gene.
Received: 15 April 1998 / Accepted: 3 August 1998 相似文献
10.
Birichevskaya LL Kvach SV Sivets GG Kalinichenko EN Zinchenko AI Mikhailopulo IA 《Biotechnology letters》2007,29(4):585-591
Enzymatic 5′-monophosphorylation and 5′-phosphatidylation of a number of β-l- and β-d-nucleosides was investigated. The first reaction, catalyzed by nucleoside phosphotransferase (NPT) from Erwinia herbicola, consisted of the transfer of the phosphate residue from p-nitrophenylphosphate (p-NPP) to the 5′-hydroxyl group of nucleoside; the second was the phospholipase d (PLD)-catalyzed transphosphatidylation of l-α-lecithin with a series of β-l- and β-d-nucleosides as the phosphatidyl acceptor resulted in the formation of the respective phospholipid-nucleoside conjugates.
Some β-l-nucleosides displayed similar or even higher substrate activity compared to the β-d-enantiomers. 相似文献
11.
The noncompetitive antagonist of ionotropic γ-aminobutyric acid (GABA) receptors 4′-ethynyl-4-n-propylbicycloorthobenzoate (EBOB) is a useful tool to probe the antagonist-binding site. In the present study, four mutants
of the human GABAA receptor β3 subunit were stably expressed in S2 cells and examined for their abilities to bind [3H]EBOB to identify the binding site of EBOB. The homo-oligomeric β3 GABA receptor was used as a housefly GABA receptor model,
as the β3 subunit has a high sequence similarity with the housefly Rdl subunit in the second membrane-spanning (M2) region.
The A274S mutation at the -1′ position in the M2 region had no effect on [3H]EBOB binding. The A277S mutation at the 2′ position led to a decrease in the affinity of EBOB for the GABA receptor. The
T281V mutant at the 6′ position and the A277S/T281V double mutant completely abolished the binding ability. A β3 GABA receptor
homology model predicts these interactions between the receptor and EBOB. These results suggest that EBOB interacts with threonine
281 and alanine 277, and that threonine 281 plays a more critical role in interacting with EBOB than alanine 277. 相似文献
12.
Kim BM Rode AB Han EJ Hong IS Hong SH 《Apoptosis : an international journal on programmed cell death》2012,17(2):200-216
In the present study, we investigated the signaling pathways implicated in the induction of apoptosis by two modified nucleosides,
5-phenylselenyl-methyl-2′-deoxyuridine (PhSe-T) and 5-methylselenyl-methyl-2′-deoxyuridine (MeSe-T), using human cancer cell
lines. The induction of apoptosis was associated with proteolytic activation of caspase-3 and -9, PARP cleavage, and decreased
levels of IAP family members, including c-IAP-1 and c-IAP-2, but had no effect on XIAP and survivin. PhSe-T and MeSe-T also
enhanced the activities of caspase-2 and -8, Bid cleavage, and the conformational activation of Bax. Additionally, nucleoside
derivative-induced apoptosis was inhibited by the selective inhibitors of caspase-2, -3, -8, and -9 and also by si-RNAs against
caspase-2, -3, -8, and -9; however, inhibition of caspase-2 and -3 was more effective at preventing apoptosis than inhibition
of caspase-8 and -9. Moreover, the inhibition of caspase-2 activation by the pharmacological inhibitor z-VDVAD-fmk or by the
knockdown of protein expression using siRNA suppressed nucleoside derivative-induced caspase-3 activation, but not vice versa.
PhSe-T and MeSe-T also induced a Δψm loss via a CsA-insensitive mechanism, ROS production, and DNA damage, including strand breaks. Moreover, ROS scavengers such
as NAC, tiron, and quercetin inhibited nucleoside derivative-induced ROS generation and apoptosis by blocking the sequential
activation of caspase-2 and -3, indicating the role of ROS in caspase-2-mediated apoptosis. Taken together, these results
indicate that caspase-2 acts upstream of caspase-3 and that caspase-2 functions in response to DNA damage in both PhSe-T-
and MeSe-T-induced apoptosis. Our results also suggest that ROS are critical regulators of the sequential activation of caspase-2
and -3 in nucleoside derivative-treated cancer cells. 相似文献
13.
Anastassia Kanavarioti 《Journal of molecular evolution》1998,46(6):622-632
Phosphoimidazolide-activated ribomononucleotides (*pN; see Scheme I) are useful substrates for the nonenzymatic synthesis
of oligonucleotides. In the presence of metal ions dilute neutral aqueous solutions of *pN (0.01 M) typically yield only small amounts of dimers and traces of oligomers; most of *pN hydrolyzes to yield nucleoside 5′-monophosphate
(5′NMP). An earlier investigation of *pN reactions in highly concentrated aqueous solutions (up to 1.4 M) showed, as expected, that the percentage yield of the condensation products increases and the yield of the hydrolysis product
correspondingly decreases with *pN concentration (Kanavarioti 1997). Here we report product distributions in reactions with
one, two, or three reactive components at the same total nucleotide concentration. *pN used as substrates were the nucleoside 5′-phosphate 2-methylimidazolides, 2-MeImpN, with N= cytidine (C), uridine (U), or guanosine (G). Reactions were conducted as self-condensations, i.e., one nucleotide only,
with two components in the three binary U,C, U,G, and C,G mixtures, and with three components in the ternary U,C,G mixture.
The products are 5′NMP, 5′,5′-pyrophosphate-, 2′,5′-, 3′,5′-linked dimers, cyclic dimers, and a small percentage of longer
oligomers. The surprising finding was that, under identical conditions, including the same total monomer concentration, the
product distribution differs substantially from one reaction to another, most likely due to changing intermolecular interactions
depending on the constituents. Even more unexpected was the observed trend according to which reactions of the U,C,G mixture
produce the highest yield of internucleotide-linked dimers, whereas the self-condensations produce the least and the reactions
with the binary mixtures produce yields that fall in between. What is remarkable is that the approximately two-fold increase
in the percentage yield of internucleotide-linked dimers is not due to a concentration effect or a catalyst, but to the increased
complexity of the system from a single to two and three components. These observations, perhaps, provide an example of how
increased complexity in relatively simple chemical systems leads to organization of the material and consequently to chemical
evolution. A possible link between prebiotic chemistry and the postulated RNA world is discussed.
Received: 12 September 1997 / Accepted: 24 November 1997 相似文献
14.
An efficient route to synthesize 3′′- and 4′′′-vinyl rutin esters has been developed by enzyme-catalyzed regioselective acylation
of rutin with divinyl dicarboxylates in organic media. Alkaline protease from Bacillus subtilis provided 3′′-O-substituted vinyl rutin esters in pyridine, and Novozym 435 gave 4′′′-O-substituted vinyl rutin esters in tert-butanol. 相似文献
15.
Flavonoids are ubiquitous secondary plant metabolites which function as protectants against UV light and pathogens and are
involved in the attraction of pollinators as well as seed and fruit dispersers. The hydroxylation pattern of the B-ring of
flavonoids is determined by the activity of two members of the vast and versatile cytochrome P450 protein (P450) family, the
flavonoid 3′-hydroxylase (F3′H) and flavonoid 3′,5′-hydroxylase (F3′5′H). Phylogenetic analysis of known sequences of F3′H
and F3′5′H indicated that F3′5′H was recruited from F3′H before the divergence of angiosperms and gymnosperms. Seven cDNAs
were isolated from species of the Asteraceae family, all of which were predicted to code for F3′Hs based on their sequences.
The recombinant proteins of four of the heterologously in yeast expressed cDNAs exhibited the expected F3′H activity but surprisingly,
three recombinant proteins showed F3′5′H activity. Phylogenetic analyses indicated the independent evolution of an Asteraceae-specific
F3′5′H. Furthermore, sequence analysis of these unusual F3′5′H cDNAs revealed an elevated rate of nonsynonymous substitutions
as typically found for duplicated genes acquiring new functions. Since F3′5′H is necessary for the synthesis of 3′,4′,5′-hydroxylated
delphinidin-derivatives, which normally provide the basis for purple to blue flower colours, the evolution of an Asteraceae-specific
F3′5′H probably reflects the adaptive value of efficient attraction of insect pollinators. 相似文献
16.
Matthieu Réfrégiers A. Laigle Béatrice Jollès Gavin V. Wheeler Laurent Chinsky 《European biophysics journal : EBJ》1997,26(3):277-281
An oligodeoxynucleotide has been synthesized, which mimics an ``antigene' oligonucleotide with a polypyrimidic stretch on
its 5′ side and is protected on its 3′ side against nucelases by a naturally forming and very stable hairpin, 5′GCGAAGC3′.
The in vitro degradation of the resulting oligonucleotide d(5′TTCTCGCGAAGC3′) has already been studied by fluorescence resonance
energy transfer (FRET) (Réfrégiers et al. 1996, J Biomol Struct Dyn 14: 365 – 371). The technique required the grafting of
fluorophores at both ends of the oligonucleotide. In the present work we have compared the hairpin formed in the presence
and in the absence of such fluorophores. This was achieved by the study of the Raman spectra (excitation at 257 nm) of the
oligodeoxynucleotides H, which forms the hairpin (5′TTCTCGCGAAGC3′), and a con-trol C (5′TTCTCCGGAAGC3′) which is unable to
form the hairpin. Resonance Raman spectroscopy with 257 nm excitation greatly favors the resonance of purines and therefore
the study of the 3′ part of the oligonucleotides. The difference spectrum obtained from resonance Raman spectra of C and H
showed marker peaks specific for hairpin formation. The search for these marker peaks in difference spectra involving the
Raman spectrum of H labeled by fluorophores and either C or H proved that the fluorophores do not modify the structure of
the hairpin but only the vibrations of the two terminal bases on which the fluorophores are grafted. The use of such labeling
is then justified in order to allow oligonucleotides protected by a hairpin on their 3′ side to be studied by fluorescence
spectroscopy.
Received: 13 December 1996 / Accepted: 7 April 1997 相似文献
17.
18.
We analyse 6,810 tRNAs, calculating the free energy of the corresponding double hairpin and ‘cigar’ secondary structures,
for which we find a high thermodynamic and statistical significance. We also analyse these tRNAs for similarity and complementarity
of their 5′ and 3′ halves or segments of them in intra-and inter-molecular comparisons. We find very clear signs that the
two halves of tRNAs had an evident evolutionary relationship, although it is not totally clear whether this was a relationship
of homology or complementarity between the 5′ and 3′ halves of tRNAs, even if there is strong evidence in favour of the homology
hypothesis. Overall, these data favour models for the origin of the tRNA molecule postulating that a duplication event involving
a hairpin structure as a precursor was involved in the origin of this molecule. Moreover, we interpret these results and favour
the hypothesis that sees the assembly of two hairpin structures sharing a homology relationship as the intermediate evolutionary
stage preceding the appearance of the cloverleaf structure of tRNA. 相似文献
19.
Cecilia Callejas Paul R. Gill Ana I. Catalán Gastón Azziz Susana Castro-Sowinski Silvia Batista 《World journal of microbiology & biotechnology》2011,27(6):1507-1512
Cyanobacterial 16S ribosomal RNA gene diversity was examined in a benthic mat on Fildes Peninsula of King George Island (62o09′54.4′′S,
58o57′20.9′′W), maritime Antarctica. Environmental DNA was isolated from the mat, a clone library of PCR-amplified 16S rRNA
gene fragments was prepared, and amplified ribosomal DNA restriction analysis (ARDRA) was done to assign clones to seven groups.
Low cyanobacterial diversity in the mat was suggested in that 83% of the clones were represented by one ARDRA group. DNA sequences
from this group had high similarity with 16S rRNA genes of Tychonema bourrellyi and T. bornetii isolates, whose geographic origins were southern Norway and Northern Ireland. Cyanobacterial morphotypes corresponding to
Tychonema have not been reported in Antarctica, however, this morphotype was previously found at Ward Hunt Lake (83oN), and in western
Europe (52oN). DNA sequences of three of the ARDRA groups had highest similarity with 16S rDNA sequences of the Tychonema group accounting for 9.4% of the clones. Sequences of the remaining three groups (7.6%) had highest similarity with 16S rRNA
genes of uncultured cyanobacteria clones from benthic mats of Lake Fryxell and fresh meltwater on the McMurdo Ice Shelf. 相似文献
20.
The thermal stability of homopolynucleotides (poly(A), poly(G), poly(C), poly(U)) and natural DNA, as well as their structural
components: nucleoside (uridine), nucleotides (uridine-5′-monaphosphate, uridine-5′-diphosphate, and uridine-5′-triphosphate)
and sugar (D-ribose) have been studied by the method of differential scanning microcalorimetry. The dependences of the heat
flow on temperature have been obtained for the compounds having individual features in the temperature range from 20 to 400°C.
All samples showed exothermic peaks at temperatures higher than 200°C (for DNA, this peak was found at a temperature of ∼160°C),
which are related to processes of irreversible thermal destruction. The temperatures of thermal destruction and the effective
energy of activation of this process for all compounds studied have been determined. The values of the effective heat of exothermal
processes have been calculated for the polynucleotides. The experimental results indicate that there is a significant difference
in the thermal stability between these homopolynucleotides and DNA, poly(G) being the most stable and DNA, the least stable.
Based on the analysis of D-ribose, nucleoside, and nucleotides, it was concluded that the sugar ring is the most probable
region of the destruction. 相似文献