• 한국식품영양학회지
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• 제1권2호
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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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• 제26권12호
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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.

• 약학회지
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• 제47권5호
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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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• 제29권3호
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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.

• 한국미생물·생명공학회지
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• 제9권1호
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• pp.45-50
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• 1981

Adenine-guanine 동시영양요구성인 Brevibacterium ammoniagenes D-21530을 사용하여 5'-IMP을 생산할 경우, 5'-IMP생성에는 탄소원으로 fructose가 glucose보다 효율적이었다. 반면에 균 생육에는 glucose를 탄소원으로 사용하는 것이 좋았다. Glucose와 fructose를 혼합하여 사용할 때 균 생육을 적절히 조절하여 5'-IMP축적을 증가시켜 줄 수 있었으며 fructose와 glucose의 혼합당에 있는 fructose의 함유율을 20∼40%범위로 하였을 때 5'-IMP생성이 최대가 되었고 fructose 단독으로 사용할 때보다 약 40% 증가되었다. 또한 영양요구성물질인 adenine과 guanine의 첨가농도가 증가함에 따라 균생육이 촉진되나 150㎎/l 이상에서는 정상상태였고, 5'-IMP생성은 50㎎/l 까지는 첨가 농도에 따라 급격히 증가하나 그 이상에서는 감소하였다.

• 농업과학연구
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• 제46권4호
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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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• 제23권9호
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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.

• 식물조직배양학회지
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• 제28권3호
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• pp.165-171
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• 2001

Adenosine deaminase 유전자를 연초의 형질전환용 표지유전자로 활용할 때 형질전환체 여부를 매우 빠르고 눈으로 직접 색깔을 확인할 수 있는 새로운 방법이 개발되었다. ADA 효소는 독성인 adenosine 유도체를 비독성인 inosine 유도체와 암모니아로 변환시키는데, 이때 형성된 암모니아를 phenol-nitoprusside와 alkaline-hypochlorite 용액을 이용하여 청색으로 변환시켜 96 well plate상에서 1시간 내에 형질전환체 여부를 쉽게 확인할 수 있게 되었다. ADA효소의 substrate로서 9-D-arabinofuranosyl adenine, cordycepin, 2'-deoxyadenosine, adenosine and xylofuranosyl adenine이 모두 가능하였으며, substrate 용액의 최적조건은 adenosine 10 mM과 pH 7.5이었다. 특히 형질전환체는 ADA효소의 inhibitor인 deoxycoformycin이 함유되어 있는 용액 속에서는 adenosine을 inosine과 암모니아로 변환시키지 못해 색깔의 변화가 없었는데, 이는 형질전환체에서 색깔의 변화는 ADA효소의 작용 때문에 일어나는 것을 의미한다. 따라서 본 연구결과는 ADA 표지유전자가 도입된 형질전환체의 확인에 있어서 GUS gene system과 같이 눈으로 직접 확인할 수 있을 뿐만 아니라 매우 작은 크기의 형질전환체 절편으로 쉽고, 빠르면, 값싸게 확인할 수 있게 되었다.

• Journal of Nutrition and Health
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• 제26권5호
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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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• 제20권6호
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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, $G^1-G^2$).