• The Korean Journal of Food And Nutrition
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• v.1 no.2
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• pp.37-42
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• 1988

In attempts to obtain IMP Producting strains, Brevibacterium ammoniagenes ATCC 6872 was treated wilts N.1.6. Adenine-guanine requiring mutants were obtained from Brevibacterium ammoniagenes ATCC 6872, and then a strain of them was selected for production of IMP and named Brevibacterium ammoniagenes No.9(ade', gu'). The production of IMP by Brevibacterium ammoniagenes nuts No.9 was about 3mg/ml for 4 day of culture. The optimal concentration of adenine and guanine was 150mg/mg.

• Archives of Pharmacal Research
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• v.26 no.12
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• pp.990-996
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• 2003

A novel carboacyclic nucleoside analogue, 9-[2-bromo-4-hydroxy-3-hydroxymethyl-2-butenyl] adenine, and its derivatives were designed and synthesized as open-chain analogues of neplanocin A. The syntheses were accomplished via the coupling of adenine or pyrimidine bases to the key intermediate allylic bromide 7. The bromide 7 was prepared from epichlorohydrin in a seven step process in a 54% overall yield. The synthesized compounds were evaluated for their antiviral activity against the polio virus, HSV and HIV.

• YAKHAK HOEJI
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• v.47 no.5
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• pp.271-275
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• 2003

Easy and efficient synthetic route of novel 4'-C methyl branched carbocyclic nucleosides is described. The installation of alkyl and aryl groups at 4'-position of carbocyclic nucleosides were successfully made via sequential [3,3]-sigmatropic rearrangement and ring-closing metathesis (RCM) starting from simple ketones such as acetol. Adenine and uracil were coupled via Pd(0) catalyzed reaction, followed by desilylation to give novel compounds 13 and 14, respectively.

• BMB Reports
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• v.29 no.3
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• pp.253-260
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• 1996

An enzyme that hydrolyzes flavin-adenine dinucleotide (FAD) was found to be present in rat liver lysosomal membrane prepared from Triton WR-1339 filled lysosomes (tritosomes) purified by flotation on sucrose. This FAD phosphohydrolase (FADase) exhibited optimal activity at pH 8.5 and had an apparent Km of approximately 3.3 mM. The activity was decreased 50~70% by dialysis against EDTA and this was restored by $Zn^{2+}$, $Mg^{+2}$, $Hg^{+2}$, and $Ca^{+2}$ ions inhibited the enzyme, but $F^-$ and molybdate had no effect. The enzyme was also inhibited by p-chloromercuribenzoate (pCMB), reduced glutathione and other thiols, cyanide, and ascorbate. The presence of ATP, ADP, AMP. ${\alpha}-{\beta}-methylene$ ATP, AMP-p-nitrophenyl phosphate (PNP), GMP, and coenzyme A (CoA) decreased the activity on FAD, but pyrimidine nucleotides, adenosine, adenine, or $NAD^+$ were without effect. Phosphate stimulated the activity slightly. FAD phosphohydrolase activity was separated from ATPase and inorganic pyrophosphatase activities by solubilization with detergents and polyacrylamide gel electrophoresis and by linear sucrose density gradient centrifugation suggesting that the enzyme is different from ATPase, inorganic pyrophosphatase, and soluble lysosomal FAD pyrophosphatase. Paper chromatography showed that FAD was hydrolyzed to flavin mononucleotide (FMN) and AMP which were further hydrolyzed to riboflavin and AMP by phosphatases known to be present in lysosomal membranes. Incubation of the intact Iysosomes with pronase showed that the active site of FAD phosphohydrolase must be oriented to the cytosol. The FAD hydrolyzing activity was detected in Golgi, microsome, and plasma membrane, but not in mitochondria or soluble lysosomal preparations.

• Microbiology and Biotechnology Letters
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• v.9 no.1
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• pp.45-50
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• 1981

The effect of growth and the carbon sources including the molar ratio of fructose to glucose was studied for the maximization of inosine-5'-monophosphate (5'-IMP) production from Brebibacterium ammoniagenes D-21530. According to experimental results, fructose was more efficient to 5'-IMP accumulation than glucose, while the latter was better for the cell growth than the former. To synchronously use glucose and fructose as carbon source is to optimally control the cell growth and maximum production of 5'-IMP without change of other conditions. The optimal weight percent of fructose to sum of glucose and fructose was 20～40%, and the productivity improvement over the utilization of fructose was about 40%. And also the optimality of purine base such as adenine and guanine were considered. The optimal concentrations of adenine and guanine were near 50㎎/l.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.885-895
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• 2019

Plant biotechnologists have long dreamed of technologies to manipulate genes in plants at will. This dream has come true partly through the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology, which now has been used to edit genes in several important crops. However, there are many restrictions in editing a gene precisely using the CRISPR/Cas9 technology because CRISPR/Cas9 may cause deletions or additions in some regions of the target gene. Several other technologies have been developed for gene targeting and precision editing. Among these, base editors might be the most practically and efficiently used compared to others. Base editors are tools which are able to cause a transition from cytosine into thymine, or from adenine into guanine very precisely on specific sequences. Cytosine base editors basically consist of nCas9, cytosine deaminase, and uracil DNA glycosylase inhibitor (UGI). Adenine base editors consist of nCas9 and adenine deaminase. These were first developed for human cells and have since also been applied successfully to crops. Base editors have been successfully applied for productivity improvement, fortification and herbicide resistance of crops. Thus, base editor technologies start to open a new era for precision gene editing or breeding in crops and might result in revolutionary changes in crop breeding and biotechnology.

• Bulletin of the Korean Chemical Society
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• v.23 no.9
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• pp.1315-1327
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• 2002

The model compounds, 8-methoxypsoralen-CH2O(CH2)n-adenine (MOPCH2OCnAd, n=2, 3, 5, 6, 8, and 10) in which 5 position of 8-methoxypsoralen (8-MOP) is linked by various lengths of polymethylene bridge to N9 of adenine. UV absorption spectra are identical with the sum of MOPCH2OC3 and adenine absorption spectra. Solvent effects on the UV absorption and fluorescence emission spectra indicate that the lowest excited singlet state is the $(\pi${\rightarrow}$\pi*)$ state. The spectral characteristics of the fluorescence of MOPCH2OCnAd are strongly dependent upon the nature of the solvents. The fluorescence emission spectra in aprotic solvents are broad and structureless due to the excimer formation through the folded conformation accelerated by hydrophobic ${\pi}-{\pi}$ stacking interaction. Increasing polarity of the protic solvents leads to higher population of unfolded conformation stabilized through favorable solvation and H-bonding, and consequently to an increase in the fluorescence intensity, fluorescence lifetime, and a shift of fluorescence maximum to longer wavelengths. The decay characteristics of the fluorescence in polar protic solvents shows two exponential decays with the lifetimes of 0.6-0.8 and 1.6-1.9 ns in 5% ethanol/water, while MOPCH2OC3 shows 0.5 and 1.7 ns fluorescence lifetimes. The long-lived component of fluorescence can be attributed to the relaxed species (i.e., the species for which the solvent reorientation (or relaxation) has occurred), while the short-lived components can be associated with the unrelaxed, or only partially relaxed, species.

• Korean Journal of Plant Tissue Culture
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• v.28 no.3
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• pp.165-171
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• 2001

New visible and fast assay system have been developed for tobacco transformant introduced with adenosine deaminase (ADA) marker gene, which converts cytotoxic adenosine analogues to non-toxic inosine analogues and ammonia. Ammonia was changed to blue color in the solution of phenol-nitoprusside and alkaline-hypochlorite. It was possible to detect activity of ADA visibly on the holes of 96 well plate using tiny explant of transgenic tobacco leaves within 1 hour incubation time. As substrates of ADA enzyme from transgenic plant on the plate, a number of adenosine analogues such as 9-D-arabinofuranosyl adenine, cordycepin, 2'-deoxyadenosine, adenosine and xylofuranosyl adenine were possible for detection of ADA activity. Optimal condition of substrate for ADA enzyme was each 10 mM and pH 7.5 in adenosine solution. Especially, transgenic plant did not convert adenosine to inosine and ammonia in the presence of ADA inhibitor deoxycoformycin, which means that ammonia produced from transgenic plant is due to expression of ADA gene. Now, we show that this detection system can be easily, sensitively, fast and cheaply as well as visibly assayed in vitro as GUS gene system with very small size of transformant explant.

• Journal of Nutrition and Health
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• v.26 no.5
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• pp.532-546
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• 1993

This study was done to investigate the effects of different dietary oils on hepatic mitochondrial lipid compositon, adenine nucleotide translocase(AdNT) and ATPase activities in carcinogen treated rats. Sixty male Sprague-Dawley rats, weighing 50∼60g, were fed three different types of dietary oil, beef tallow(BT), corn oil(CO) and sardine oil(SO) at 15% by weight for 14 weeks. Three weeks after feeding rats were intraperitoneally injected with a single dose of diethylnitrosamine(200mg/Kg BW). After five weeks rate fed 0.02% acetylaminofluorene contating diet for 6 weeks, and after seven weeks 0.05% phenobarbital containing diet for 7 weeks. At 14th week, rats were sacrificed and hepatic mitochondrial lipid composition, AdNT and ATPase activities were determined. Percent liver weight per body weight was significantly by carcinogen treatment. Analysis of mitochondrial lipid composition showed that body cholesterol and phospholipid contents were not affected by dietary oils but significantly increased by carcinogen treatment. Individual phospholipid composition as well as phosphatidyl ethanolamine/phosphatidyl choline ratio were altered by either dietary oils or carcinogen treatment. Fatty acid composition was changed by dietary oils but not much by carcinogen treatment. AdNT activity was affected by dietary oils in only carcinogen treated groups. ATPase activity was affected by dietary oils in only carcinogen nontreated groups. These data indicate that both dietary oils and caricinogen treatment can change mitochondrial lipid composition and thereby change AdNT and ATPase activities. Particularly effects of carcinogen treatment on cholesterol/phopholipid ratio, phospholipid compositon and ATPase activity were different among dietary oil groups. Therefore it is suggested that different dietary oils can somewhat modulate the changes of mitochnodrial lipid composition and membrane bound enzyme activites during hepatocarcinogenesis.

• Archives of Pharmacal Research
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• v.20 no.6
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• pp.550-554
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• 1997

Chlorambucil is known to alkylate primarily N7 of guanine and N3 of adenine to induce DNA monofunctional adducts and interstrand cross-links (ISC). We have investigated the sequence specificity for DNA ISC induced by chlorambucil using duplex oligomers containing a defined cross-linkable sequences $ 5^{I}-A*TT, 5^{I}-G*TTor5^{I}-G*CC$ under bar which asterisk indicates the potential cross-linking site and underlined base indicates the potential cross-linking site on the opposite strand. An analysis of 20% denaturing polyacrylamide gel electrophoresis showed that chlorambucil was albe to induce DNA ISC in the duplex oligomers containing a sequence $5^I-GCC$. The formation of DNA ISC was not observed in the duplex oligomers containing sequences $5^I-ATT$. or $5^I-GTT$. These results indicate that chlorambucil induces guanine-guanine DNA ISC but not guanine-adenine or adenine-adenine DNA ISC. In addition, we have tested the ability of chlorambucil to induce DNA ISC within $5^I-GNNC$ or $5^I-GNNC$sequences using duplex oligomers containing the sequence$5^I-G^4G^3G^2^C$. The result of DNA strand cleavage assay showed that DNA ISC was formed at the $5^I-GGC$ sequence (an 1,3 cross-link, $G^1-G^3$) but not at $5^I-GGGC$ (an 1,4 cross-link, $G^1-G^4$) or $5^I-GC$ sequence (an 1,2 cross-link, $G^1-G^2$).