• Journal of Life Science
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• v.9 no.1
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• pp.64-68
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• 1999

The properties of purified intracellular adenosine deaminase (adenosine aminohydrolase, EC 3.5.4.4) of Nocardioides sp. J-326TK isolated from soil have been studied. The enzyme deaminated adenosine and 2`-deoxyadenosine and the respective {TEX}$K_{M}${/TEX} values were 4.0×{TEX}$10^{-4}${/TEX} M and 5.0× {TEX}$10^{-4}${/TEX} M, but the enzyme was not active on 8-bromoadenosine, 6-methylaminopurine riboside, ATP, ADP, 2`-AMP, 3`-AMP, 5`-AMP, dAMP, cAMP, NAD, FAD, NADP and adenine. The enzyme activity was strongly inhibited by the addition of {TEX}$Hg^{2+}${/TEX} and {TEX}$Ag^{+}${/TEX}, {TEX}$Cu^{2+}${/TEX}, {TEX}$Co^{2+}${/TEX} and {TEX}$Mn^{2+}${/TEX} also inhibited the activity but much less extent. The effect of alkyl reagents, metal chelating reagents and certain other compounds on the enzyme activity were also examined. No reagent activated the enzyme. On the contrary, the enzyme reaction was slightly inhibited by o-phenanthroline and 6-benzyladenosine.

• Journal of Plant Biology
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• v.21 no.1_4
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• pp.21-27
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• 1978

The effect of tannic acid on GAs and cyclic-AMP promoted amylase induction in barley aleurone layers was examined. Of a variety of adenine compounds, only cyclic-AMP and ADP showed significant activity, and these activities were promoted by addition of theophylline to the incubation medium. When aleurone layers of barley endosperm tissues were incubated with GAs in the presence of tannic acid, the amylase activity in the incubation medium was reduced. Cyclic-AMP induced amylase activity was also reduced by additiion of tannic acid. The cyclic-AMP response promoted was more sensitive to tannin inhibition than GAs response. The inhibitory effect of tannic acid shwoed reversibility by addition of higher concentration of GAs or cyclic-AMP. The tannic acid effect on GAs response was also recovered by addition of a higher concentration of cyclic-AMP. Experiment with polyacrylamide disc electrophoresis showed different isozyme patterns according to the additions in the incubation medium. Inhibitory effects of decursinol and coumarin was compared with that of tannic acid. They showed different zymogram patterns.

• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1216-1219
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• 2004

Spinoside, new coumaroyl flavone glycoside was isolated from the n-butanol fraction of the mathanolic extract of the whole plant of Amaranthus spinosus and assigned the structure 7-pcoumaroyl apigenin 4-O-${\beta}$ -D-glucopyranoside (1) on the basis of spectroscopic techniques including 1D and 2D NMR spectroscopy. In addition ${\alpha}$ - xylofuranosyl uracil (2), ${\beta}$ -D-ribofuranosyl adenine (3) and ${\beta}$ -sitosterol glucoside (4) have also been isolated for the first time from this species.

• Animal cells and systems
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• v.2 no.3
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• pp.351-353
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• 1998

A 245 bp segment of E. coli chromosomal replication origin, oriC, contains 11 repeats of the GATC sequence in which adenine is methylated by Dam methylase. Newly replicated oriC is hemimethylated. The parental strand of the newly replicated oriC is methylated, but the nascent strand is not yet methylated until methylated by Dam methylase. The hemimethylated oriC plays an important role in the regulation of chromosomal replication. Activity in the seqA mutant was identified to bind preferentially to hemimethylated DNA, but not to fully-methylated DNA. This activity may participate in the sequestration of initiation of chromosomal replication.

• Korean Journal of Microbiology
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• v.10 no.3
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• pp.109-116
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• 1972

Three strains among 120 adenineless mutants of Brevibacterium ammoniagenes described in the previous paper were screened out to accumulate UV absorbing substances in the culture broth. It was analyzed to be 5'-inosinic acid and hypoxanthine by means of two dimensional paper chromatography, UV absorption spectra and periodate oxidation. 5'-IMP was isolated from the culture broth of the mutant No. 203 with anion-exchange resin amberite IRA-400 and recrystallized from ethanol. It was proved identical to authentic sample by Infra-red absorption spectrum. The growth responses of the mutant No. 2013 were demonstrated to require adenine, but not with adenosine and 5'-AMP.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.71-71
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• 2003

The quinolinic acid(QA) phosphoribosyltransferase (PRTase) (EC 2.4.2.19), is a key enzyme involved in NAD$\^$+/ biosynthesis in prokaryotes and eukaryotes, The QAPRTase produces nicotinic acid mononucleotide (NAMN) from QA and 5-phosphoribosyl-1-pyrophosphate (PRPP). For this reaction, the QA is decarboxylated (Fig.1). Produced NAMN is used to a synthesis of nicotinate adenine dinucleotide(NAD$\^$+/).

• Bulletin of the Korean Chemical Society
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• v.25 no.8
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• pp.1211-1216
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• 2004

The interaction of the antitumour agent doxorubicin with calf thymus DNA is investigated in an aqueous solution at a pH level of 6-7 with molar ratios of 1/10. A UV-resonance Raman spectroscopy and surface enhanced Raman spectroscopy are used to determine the doxorubicin binding sites and the structural variations of doxorubicin-DNA complexes in an aqueous solution. Doxorubicin intercalates with adenine and guanine via a hydrogen bond formation between the N7 positions of purine bases and the hydroxyl group of doxorubicin.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1812-1816
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• 2004

The stereoselective synthesis 4′,6′-dually branched carbocyclic nucleosides was accomplished in this study. The introduction of a methyl group in the 6′$({\alpha})$-position was accomplished by Felkin-Anh controlled alkylation. The construction of the required 4′$({\alpha})$-quaternary carbon was carried out using a [3,3]-sigmatropic rearrangement. Bis-vinyl 6 was successfully cyclized using a Grubbs' catalyst II. The natural bases (adenine, cytosine) were efficiently coupled using a Pd(0) catalyst. When the synthesized compounds were examined for their activity against several viruses such as the HIV-1, HSV-1, HSV-2 and HCMV, the cytosine analogue 13 exhibited good antiviral activity against the HCMV.

• Animal cells and systems
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• v.3 no.1
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• pp.69-72
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• 1999

A tandemly repeated DNA sequence was identified and characterized y the combined RAPD and FISH data from a total genomic DNA of Welsh onion (Allium fistulosum). A clone containing this repeating sequence was selected and sequenced. This repeating unit of 314 bp inserted into pAf 072 contained 54.1% adenine and thymine residues, and showed the primer sequence used, 5'-GAAACGGGTG-3', in both terminals of the sequence. Fluorescence in situ hybridization using this tandemly repeated sequence as a probe indicated that the detected sites were coincident with the major C-banded constitutive heterochromatin in the terminal regions of both arms of all 6 chromosomes.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4007-4014
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• 2012

Efficient synthetic route to novel 4'-fluorinated 5'-deoxythreosyl phosphonic acid nucleosides was described from glyceraldehyde using Horner-Emmons reaction in the presence of triethyl ${\alpha}$-fluorophosphonoacetate. Glycosylation reaction of nucleosidic bases with glycosly donor 14 gave the nucleosides which were further phosphonated and hydrolyzed to reach desired nucleoside analogues. Synthesized nucleoside analogues 18, 21, 25 and 28 were tested for anti-HIV activity as well as cytotoxicity. Adenine derivatives 18 and 21 showed significant anti-HIV activity up to $100{\mu}M$.