• 한국미생물·생명공학회지
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• 제24권3호
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• pp.268-273
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• 1996

An extremely cadmium tolerant yeast, Hansenula anomala B-7 used to determine the modification of the intracellular enzyme activities by cadmium ion. The activities of alcohol dehydrogenase, phosphofructokinase, and cytidine deaminase were decreased up to 90%, 40%, and 86% compa- red with the control by 1 mM cadmium nitrate respectively, but the activities of malate dehydrogenase, 6- phosphogluconate dehydrogenase, cytochrome c oxidase, and alkaline phosphatase were increased up to 440%, 136%, 260% and 155% compared with the control by 1 mM cadmium nitrate respectively. These results show that the activities of the enzymes participating in Embden-Mayerhof pathway (e.g. anaerobic metabolism) were reduced by cadmium, but those involved in hexose monophosphate pathway and tricarboxylic acid cycle (e.g. aerobic metabolism) were stimulated in contrast. It has been suggested that the diminished activity of cytidine deaminase in pyrimidine nucleotide dissimilation occured due to the inhibited nucleotide dissimilation by cadmium ion; the enhanced activity of cytochrome c oxidase was specifically required in order to oxidize a raised amount of NADH and NADPH due to the increased aerobic metabolism.

• 환경생물
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• 제21권1호
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• pp.56-59
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• 2003

The Salmonella typhimurium cdd gene encoding cytidine deaminase (cyti-dine/2'-deoxycytidine aminohydrolase; EC 3.5.4.5.) was isolated through shotgun clon-ing by complementation of the E. coli odd mutation. By subsequent deletion and sub-cloning from the original 3.7 Kb of EcoRI insert (pSAMI), the precise region of the cdd structural gene is located around the BglII site in the middle part of 1.7 Kb of NruI/PvuI segment. The 1.7 Kb containing odd gene wag subcloned to the pUC18 vector and the nucleotide sequence of the cdd gene was determined. When the putative ribosorne-binding site (Shine-Dalgarno sequence) and initiation codon were predicted to be GAGG at the position 459 and ATG at the position 470, respectively, there was an open reading frame of 885 nucleotides, encoding an 294 amino acid protein. The cdd gene expression in E. coli JF611/pSAMI was amplified about 50 fold compared to that of the wild type. The cdd gene expression was maintained in the stationary phase after rea-ching the peak in the late logarithmic phase.

• Archives of Pharmacal Research
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• 제8권3호
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• pp.109-117
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• 1985

The interaction of salicylic acid (S. A.), salicylamide (S,M) with nucleic acid base derivatives such as 9-ethyl adenine (A), 1-cyclohexyl uracil (U), 2', 3'-benzylidine-5' trityl-cytidine (C), gaunosine-2', 3', 5'-isobutylate (G) has been spectroscopically investigated to determine the binding mechanism. NMR and IR spectra were measured in nonpolar solvents. The association constant K of the formation of complex was calculated from the IR spectra. Compounds S. A. and A form a 1:1 or 1:2 cyclic hydrogen-bonded complex depending on the sample concentration. Compounds S. A. and U form a 1:1 or 1:2 hydrogen-bonded complex on the sample concentration. Compounds S. A. and C form a 2:1 hydrogen-bonded complex at low concentration (0.0016M). Compound S. A. binds compound G, but its binding does not completely break the self-association of compound G, Compound S. M. binds compounds A. U. C. G. very weakly.

• Journal of Microbiology and Biotechnology
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• 제9권2호
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• pp.173-178
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• 1999

The extracellular cytosine deaminase (EC 3.5.4.1) from Chromobacterium violaceum YK 391 was purified 264.7-fold with an overall yield of 14.3%. The enzyme was for the first time homogeneous by the criteria of polyacrylamide gel electrophoresis performed in the absence and in the presence of sodium dodecyl sulfate. The molecular weight of the purified enzyme was estimated to be about 156 kDa. The enzyme consisted of two identical subunits of approximate molecular weight 78 kDa. The isoelectric point of the enzyme was pH 5.55. The enzyme had a pH optimum of 7.5 and a temperature optimum of around 40 to $45^{\circ}C$. Besides cytosine, the enzyme deaminated 5-fluorocytosine, cytidine, 5-methylcytosine, and 6-azacytosine, but not 5-azacytosine. The extracellular cytosine deaminase is believed to be unique because it was active not only on cytosine but also on cytidine. The apparent $K_m$ values for cytosine, 5-fluorocytosine, cytidine, and 5-methylcytosine were determined to be 1.55 mM, 5.52 mM, 10.4 mM, and 67.2 mM, respectively. The enzyme activity was strongly inhibited by heavy metal ions such as $Fe^{2+},Pb^{2+},Cd^{2+},Zn^{2+}, Hg^{2+}, and Cu^{2+}$ at 1 mM, and completely by $\alpha,\alpha$'-dipyridyl, and $\rho$-chloromercuribenzoate at 1 mM, and weakly inhibited by 1mM ο-phenanthroline. The enzyme activity was not affected by various nucleosides and nucleotides.

• Molecules and Cells
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• 제40권11호
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• pp.823-827
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• 2017

Genome editing using programmable nucleases such as CRISPR/Cas9 or Cpf1 has emerged as powerful tools for gene knock-out or knock-in in various organisms. While most genetic diseases are caused by point mutations, these genome-editing approaches are inefficient in inducing single-nucleotide substitutions. Recently, Cas9-linked cytidine deaminases, named base editors (BEs), have been shown to convert cytidine to uridine efficiently, leading to targeted single-base pair substitutions in human cells and organisms. Here, we first report on the generation of Xenopus laevis mutants with targeted single-base pair substitutions using this RNA-guided programmable deaminase. Injection of base editor 3 (BE3) ribonucleoprotein targeting the tyrosinase (tyr) gene in early embryos can induce site-specific base conversions with the rates of up to 20.5%, resulting in oculocutaneous albinism phenotypes without off-target mutations. We further test this base-editing system by targeting the tp53 gene with the result that the expected single-base pair substitutions are observed at the target site. Collectively, these data establish that the programmable deaminases are efficient tools for creating targeted point mutations for human disease modeling in Xenopus.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.2061-2064
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• 2010

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.497-497
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• 2003

• 한국식품영양과학회지
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• 제12권1호
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• pp.1-6
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• 1983

인삼(人蔘)과 오가피중(五加皮中)의 핵산계(核酸系) 성분(成分)을 HPLC로 분리(分離) 정량(定量)하여 다음과 같은 결과를 얻었다. 1. 동일한 원료수삼에서 제조한 백삼(白蔘)과 홍삼(紅蔘)의 핵산유리염기(核酸遊離鹽基)와 nucleoside의 조성이 거의 같았다. 2. 인삼(人蔘)과 오가피(五加皮)중의 nucleosides 함량에서 adenosine, guanosine, cytidine 등이 특징적(特徵的)인 차이(差異)를 나타냈으며 인삼속(人蔘屬)이 약(約) 3배(倍)이상 많게 나타났다. 그러나 tymidine과 inosine은 오가피속(五加皮屬)이 다소 많았다. 3. nucleobase 함량면에서는 인삼(人蔘)이나 오가피간(五加皮間)에 비슷한 함량으로 1~2mg/100g를 함유했다.

• Molecules and Cells
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• 제19권3호
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• pp.445-451
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• 2005

Activation-induced cytidine deaminase (AID) is needed for Ig class switch recombination (CSR). We explored the effect of LPS on the expression of AID during B cell differentiation, and the role of AID in IgA isotype expression. In normal spleen B cells, LPS increased AID transcription up to 48 h post-stimulation, i.e. around the time of Ig CSR. TGF-${\beta}1$ and AID were required for IgA expression, and LPS contributed to $TGF{\beta}1$-induced IgA production largely by inducing AID. Interestingly, LPS repressed AID transcription in $sIgA^+$ B cells but still stimulated IgA production mainly by increasing the rate of IgA secretion. Our data indicate that LPS contributes to $TGF{\beta}1$-induced IgA isotype expression in at least two ways: by stimulating AID transcription before CSR and by enhancing the IgA secretion rate after CSR.

• The Korean Journal of Physiology and Pharmacology
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• 제23권3호
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• pp.181-189
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• 2019

Curcumin, an active ingredient of Curcuma longa L., can reduce the concentration of low-density lipoproteins in plasma, in different ways. We had first reported that curcumin exhibits hypocholesterolemic properties by improving the apolipoprotein B (apoB) mRNA editing in primary rat hepatocytes. However, the role of curcumin in the regulation of apoB mRNA editing is not clear. Thus, we investigated the effect of curcumin on the expression of multiple editing components of apoB mRNA cytidine deamination to uridine (C-to-U) editosome. Our results demonstrated that treatment with $50{\mu}M$ curcumin markedly increased the amount of edited apoB mRNA in primary mouse hepatocytes from 5.13%-8.05% to 27.63%-35.61%, and significantly elevated the levels of the core components apoB editing catalytic polypeptide-1 (APOBEC-1), apobec-1 complementation factor (ACF), and RNA-binding-motif-protein-47 (RBM47), as well as suppressed the level of the inhibitory component glycine-arginine-tyrosine-rich RNA binding protein. Moreover, the increased apoB RNA editing by $50{\mu}M$ curcumin was significantly reduced by siRNA-mediated APOBEC-1, ACF, and RBM47 knockdown. These findings suggest that curcumin modulates apoB mRNA editing by coordinating the multiple editing components of the edito-some in primary hepatocytes. Our data provided evidence for curcumin to be used therapeutically to prevent atherosclerosis.