• 미생물학회지
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• 제32권2호
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• pp.155-162
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• 1994

포도당을 이용하여 성장하고 있는 호기성 일산화탄소 산화 세균인 Acinetobacter sp. Strain JC1 DSM 3808애 존재하는 catalase의 활성은 지수성장기 중반에서 높게 나타났으나, 지수성장기 후반 및 정체기 초기에서 낮아졌다가 정체기 중기에서 급격히 증가한 후 다시 감소하였다. 이 세균에는 세종류(Cat1, Cat2, Cat3)의 catalase가 존재하였는데, Cat1과 Cat3의 활성은 성장시기에 따라 큰 차이를 보이지 않았으나 Cat2의 활성은 성장시기에 따라 큰 변화를 나타내었다. Cat3는 이 세균이 포도당을 이용하여 성장할 때만 생성되었고, 일산화탄소나 메탄올을 이용하여 성장할 때는 생성되지 않았다. 세포추출액을 ethanol과 chloroform으로 처리한 후 활성염색을 하였을 때 Cat1과 Cat3의 활성은 안정하였으나 Cat2는 활성을 상실하였다. 세포추출액을 20mM $H_2O_2$와 3-amino-1,2,4-triazole(AT)을 처리하였을 때 Cat1과 Cat3의 활성이 반감되었고, Cat2는 $H_2O_2$에 의해서는 불활성되었으나 AT의 영향은 받지 않았다. Cat1은 80$^{\circ}C$ 1분간 열처리후에도 활성을 나타내었으나, Cat2와 Cat3는 60$^{\circ}C$와 70$^{\circ}C$에서 1분간의 열처리 후 각각 활성을 상실하였다. Cat2는 catalase 활성외에 peroxidase의 활성도 나타내었다. 일곱단계의 과정을 거쳐 포도당에서 성장시에만 생성되는 Cat3를 정제하였다. 정제된 Cat3의 크기는 150,000이었고, 63,000의 크기를 가진 두개의 동일한 소단위로 구성되어 있었으며, $H_2O_2$에 대한 K_m값은 39mM과 58mM로 나타났다. 정제된 효소의 활성을 위한 최적 pH는 7.0이었으나 전반적으로 pH 6~9에서 비슷하게 높은 활성을 나타내었다. 정제된 효소의 최적온도는 40$^{\circ}C$이었으며 20~50$^{\circ}C$에서 비슷한 활성을 나타내었고, 30$^{\circ}C$에서는 60분동안 효소활성이 거의 상실되지 않았다. 정제된 효소는 ethanol과 chloroform 처리에는 안정하였으나 12mM AT 와 0.1mM $NaN_3$ 및 1mM KCN에 의해 90% 이상의 활성이 억제되었다.

• Archives of Pharmacal Research
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• 제20권5호
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• pp.404-409
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• 1997

Trout CYP1A-CAT expression construct was generated by cloning -3.5 Kb $5^I$ flanking DNA of trout liver CYP1A gene in front of CAT gene at pCAT-basic vector. Hepa 1 cells, which are known to contain a functional arylhydrbcarbon $receptor^I$ were transfected with trout CYP1A-CAT using lipofectin. 3-Methylcholanthrene (1 nM) was added into hepa 1 cells in culture in order to examine if $5^I$ flanking DNA of trout CYP1A gene could interact with mouse transactivating factors to bring about transcription of the chloramphenicol acetyltransferase(CAT) reporter gene. The level of CAT protein was measured by CAT ELISA and the level of CAT mRNA was determined by RTPCR. The treatment of 1 nM 3-methylcholanthrene resulted in two fold increases in CAT protein as well as CAT mRNA compared to untreated control hepa 1 cells. These data indicate that arylhydrocarbon receptors of mouse hepa 1 cells are functional to activate exogenously transfected trout CYP1A-CAT construct in terms of both transcription and translation of CAT. We also examined the effect of 3-methylcholanthrene on endogenous cyplal activity in hepa 1 cell. 3-Methylcholanthrene (1 nM) treatment to hepa 1 cells trahsfected with trout CYP1A-CAT construct stimulated the level of cyp1a1 mRNA by two folds and the activity of ethoxyresorufin-O-deethylase by two fold compared to that of control cells. In this study we reported that trout CYP1A-CAT reporter gene expression construct could be expressed by 3-methylcholanthrene treatment in mouse hepa 1 cells. Thus trout CYP1A-CAT could serve as a good model to study the mechanism of regulation of CYP1A1 gene expression.

• Molecules and Cells
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• 제20권2호
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• pp.247-255
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• 2005

Three different catalase cDNA clones (CaCat1, CaCat2, and CaCat3) were isolated from hot pepper (Capsicum annuum L.), and their expression patterns were analyzed at the levels of mRNA and enzyme activity. Northern hybridization showed that the three catalase genes were differentially expressed in various organs, and that expression of CaCat1 and CaCat2 was regulated differently by the circadian rhythm. In situ hybridization revealed different spatial distributions of CaCat1 and CaCat2 transcripts in leaf and stem. In response to wounding and paraquat treatment, CaCat1 mRNA increased at 4-12 h in both paraquat-treated and systemic leaves. In contrast, wounding had no significant effect on expression of the catalase genes. The increase of catalase activity in the paraquat-treated and systemic leaves paralleled that of CaCat1 mRNA, but did not match that of CaCat1 mRNA in paraquat-treated stems. Our results suggest that CaCat1 may play a role in responses to environmental stresses.

• Applied Biological Chemistry
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• 제49권4호
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• pp.287-292
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• 2006

명조건과 암조건에서 카드뮴이 벼 유묘 뿌리와 줄기의 카탈라제 총 활성과 동위효소 발현에 미치는 영향을 조사하였다. 카드뮴을 처리하면 명조건과 암조건의 뿌리와 줄기에서 과산화수소 함량이 현저하게 증가하였다. 뿌리의 카탈라제 동위효소는 잎과는 서로 다른 조직 특이적 발현양상을 보여주었다. 또한 카드뮴을 처리하게 되면 명조건 뿌리는 암조건 뿌리와 카탈라제 동위효소의 발현 패턴에 차이를 보였다. 1 mM 카드뮴 처리에 의하여 명조건 뿌리의 카탈라제 총 활성은 약 16배 증가하였는데 이러한 활성증가는 동위효소 CAT1l과 CAT2의 증가에 의한 것이었다. 반면 암조건 뿌리의 카탈라제는 0.1mM 카드뮴에 의하여 약 3배 증가하였느나, 0.5와 1mM카드뮴에 의하여 오히려 효소활성이 감소하였다. 0.1mM카드뮴에 의한 효소활성 증가는 CAT1, CAT3, CAT4 동위효소의 활성 증가에 기인하였으나 카드뮴 농도를 더 높였을때 CAT2와 CAT4가 감소하였다. 대조군 잎에는 양극 동위효소인 CATc, 중성 동위효소인 CATn와 음극 동위효소인 CAT1가 존재하였다. 잎에서는 명조건과 암조건 모두에서 카드뮴을 처리하여도 카탈라제 활성과 동위효소 발현에 차이가 없었다. 이러한 결과들은 카드뮴에 의한 뿌리 카탈라제 효소의 발현변화는 빛에 의하여 조절되지만 잎 카탈라제의 발현은 빛에 의하여 조절되지 않음을 보여준다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2021년도 추계학술대회
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• pp.682-685
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• 2021

해양수산부가 추진하고 있는 전자 어구 실명제를 위한 어구 자동식별 모니터링 시스템의 선박에 설치되는 IoT 통신 모듈의 서비스 확장성을 제고하기 위하여 3GPP Release13 표준화 기술인 LTE Cat. M1 모듈의 설계와 제작에 대해 기술한다.

• Journal of Microbiology
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• 제39권3호
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• pp.168-176
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• 2001

Five different types of catalases from photosynthetic bacterium Rhodospirillum rubrum S1 grown aerobically in the dark were found in this study, and designated Catl (350 kDa), Cat2 (323 kDa), Cat3 (266 kDa), Cat4 (246 kDa), and Cat5 (238 kDa). Analysis of native PAGE revealed that Cat2, Cat3, and Cat4 were also produced in the cells anaerobically grown in the light. It is notable that only Cat2 was expressed much more strongly in response to the anaerobic condition. Enzyme activity staining demonstrated that Cat3 and Cat4 had bifunctional catalase-peroxidase activities, while Catl, Cat2, and Cat5 were typical monofunctional catalases. S1 cells grown aerobically in the presence of malate as the sole source of carbon exhibited an apparent catalase Km value of 10 mM and a Vmax of about 705 U/mg protein at late stationary growth phase. The catalase activity of Sl cells grown in the anaerobic environment exhibited a much lower Vmax of about 109 U/mg protein at late logarithmic growth phase. The catalytic activity was stable in the broad range of temperatures (30$\^{C}$-60$\^{C}$), and pH (6.0-10.0). R. rubrum S1 was much more resistant to H$_2$O$_2$in the stationary growth phase than in the exponential growth phase regardless of growth conditions. Cells of stationary growth phase treated with 15 mM H$_2$O$_2$for 1 h showed 3-fold higher catalase activities than the untreated cells. In addition, L-glutamate induced an 80-fold increase in total catalase activity of R. rubrum S1 compared with magic acid. Through fraction analyses of S1 cells, Cat2, Cat3, Cat4 and Cat5 were found in both cytoplasm and periplasm, while Catl was localized only in the cytoplasm.

• Journal of Microbiology
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• 제44권4호
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• pp.447-452
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• 2006

The murine ecotropic retroviral receptor has been demonstrated to function as a mouse cationic amino acid transporter 1(mCAT1), and is comprised of multiple membranespanning domains. Feral mouse (Mus dunni) cells are not susceptible to infection by the ecotropic Moloney murine leukemia virus (MoMLV), although they can be infected by other ecotropic murine leukemia viruses, including Friend MLV and Rauscher MLV. The relative inability of MoMLV to replicate in M. dunni cells has been attributed to two amino acids $(V_{214}\;and\;G_{236})$ located within the third extracellular loop of the M. dunni CAT1 receptor (dCAT1). Via the exchange of the third extracellular loop of the mCAT1 cDNA encoding receptor from the permissive mouse and the corresponding portion of cDNA encoding for the nonpermissive M. dunni receptor, we have identified the most critical amino acid residue, which is a glycine located at position 236 within the third extracellular loop of dCAT1. We also attempted to determine the role of the third extracellular loop of the M. dunni CAT1 receptor with regard to the formation of the syncytium. The relationship between dCAT1 and virus-induced syncytia was suggested initially by our previous identification of two MLV isolates (S82F in Moloney and S84A in Friend MLV), both of which are uniquely cytopathic in M. dunni cells. In an attempt to determine the relationship existing between dCAT1 and the virally-induced syncytia, we infected 293-dCAT1 or chimeric dCAT1 cells with the S82F pseudotype virus. The S82F pseudotype virus did not induce the formation of syncytia, but did show increased susceptibility to 293 cells expressing dCATl. The results of our study indicate that S82F-induced syncytium formation may be the result of cell-cell fusion, but not virus-cell fusion.

• Mycobiology
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• 제41권3호
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• pp.145-148
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• 2013

Vegetative growth signaling of the opportunistic human pathogenic fungus Aspergillus fumigatus is mediated by GpaA ($G{\alpha}$). FlbA is a regulator of G protein signaling, which attenuates GpaA-mediated growth signaling in this fungus. The flbA deletion (${\Delta}flbA$) and the constitutively active GpaA ($GpaA^{Q204L}$) mutants exhibit enhanced proliferation, precocious autolysis, and reduced asexual sporulation. In this study, we demonstrate that both mutants also show enhanced tolerance against $H_2O_2$ and their radial growth was approximately 1.6 fold higher than that of wild type (WT) in medium with 10 mM $H_2O_2$. We performed quantitative PCR (qRT-PCR) for examination of mRNA levels of three catalase encoding genes (catA, cat1, and cat2) in WT and the two mutants. According to the results, while levels of spore-specific catA mRNA were comparable among the three strains, cat1 and cat2 mRNA levels were significantly higher in the two mutants than in WT. In particular, the ${\Delta}flbA$ mutant showed significantly enhanced and prolonged expression of cat1 and precocious expression of cat2. In accordance with this result, activity of the Cat1 protein in the ${\Delta}flbA$ mutant was higher than that of $gpaA^{Q204L}$ and WT strains. For activity of the Cat2 protein, both mutants began to show enhanced activity at 48 and 72 hr of growth compared to WT. These results lead to the conclusion that GpaA activates expression and activity of cat1 and cat2, whereas FlbA plays an antagonistic role in control of catalases, leading to balanced responses to neutralizing the toxicity of reactive oxygen species.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1995년도 춘계학술대회
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• pp.128-128
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• 1995

To investigate the mechanism of the regulation of cytochrome P450IA1 gene expression, ethoxyresorufin deethylase(EROD) and benzo(a)pyrene hydroxylase in B6 mouse liver, in isolated perfused rat liver system. and in B6 mouse hepatocyte Hepa-I cells were examined. In C57BL/6N mouse, 3-methylcholan- throne( 3MC ) treatment have resulted in the stimulation of EROD activity based on fluorometry by 2.79 fold comparirng with that of control. Measurement of mRNA of cytochrome P450 was carried out by either nothern blot or dot blot analysis. Findings are similar to that of studies with enzymes. Furhtermore, when RTPCR method was applied to detect mRNA in Hepa I cell and liver tissues the results were more clear. Cytochrome P450IA1 upstream DNA containing CAT construct was transfected into Hepa-1 cells. After transfection of CAT construct, 3MC and flavonoids, such as, chrysin, hesperetin, kaempferol, morin, myricetin and aminoyrine were treated. 48 Hours after treatments, cells were harvested and assayed for CAT mRNA by RTPCR. 3MC treatment to hepa I cells transfected with trout P450IA1-CAT construct increased CAT mRNA by 2.81 fold when it was compared with that of control. This increase CAT mRNA was decreased by concomitantly treated flavonoids and aminopyrine. The level of CAT protein was 29.2-58.0% of 3MC stimulated CAT protein. Results of this study suggested that RTPCR seems to be a very good method to study regulation of gene expression in liver tissue or Hepa cells.

• Journal of Microbiology and Biotechnology
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• 제7권1호
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• pp.21-24
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• 1997

Chloramphenicol acetyl transferase (CAT) protein and mRNA levels in E. coli were determined following induction of a tac::cat construct by isopropyl-${\beta}$-thiogalactopyranoside (IPTG). High cat mRNA levels did not directly reflect CAT protein levels, in either shakeflask experiments or fermentations. Furthermore, concentrations of IPTG resulting in the highest levels of expression of cat mRNA, were different to those resulting in highest levels of CAT protein. The data suggest that high transcriptional activities lead to limitations at the translational level.