• Journal of Microbiology
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• 제38권3호
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• pp.156-159
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• 2000

The cttl+ gene in Schizosaccharomyces pombe encoeds a catalse responsible for H2O2-resistance of this organism as judged by the H2O2-sensitive phenotype of the ctt1Δ mutant. In this study, we investigated the subcellular localization of the Ctt1 gene product. In wild type cells catalase activity was detected in the organelle fraction as well as in the cytosol. The ctt1Δ mutant contained no catalase activity, indicating that both cytosolic and organellar catalases are the products of a single ctt1+ gene. Western bolt analysis revealed two catalase bands, both of which disappeared in the ctt1Δ mutant. The major, fastermigrating band existed in the cytosol whereas the monor, slower-migrating band appeared to be located in organelles, most likely in peroxisomes. These results suggest that the ctt1+ gene product targeted to the peroxisome is a modified form of the one in the cytosol.

• 생물정신의학
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• 제9권1호
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• pp.62-67
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• 2002

본 연구에서는 정신분열병과 antioxidant defense system사이의 관련성을 알아보기 위해 항산화 효소(antioxidant enzyme)중의 하나인 CAT의 유전자 다형성을 한국인 정신분열병 환자군과 대조군 사이에서 비교 분석하였다. 환자군과 대조군의 HinfI 다형성에 따른 CAT유전자형과 대립유전자형의 빈도는 통계적으로 유의한 차이는 없었지만, 여성 정신분열병 환자군과 여성 대조군 사이의 유전자형 빈도에서는 통계적으로 유의한 차이를 나타내었다. 연구결과 CAT유전자가 여성 정신분열병과 관련이 있을 수 있다는 가능성이 제시된다.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1998년도 Advances in Ginseng Research - Proceedings of the 7th International Symposium on Ginseng -
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• pp.63-70
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• 1998

Superoxide dismutase (SOD) and catalase constitute the first coordinated unit of defense against reactive oxygen species. Here, we examined the effect of ginseng saponins on the induction of SOD and catalase gene expression. To explore this possibility, the upstream regulatory promoter region of Cu/Zn superoxide dismutase (SODI) and catalase genes were linked to the chloramphenicol acetyl-transferase (CATI structural gene and introduced into human hepatoma HepG2 cells. Total saponin and panaxatriol did not activate the transcription of SODI and catalase genes but panaxadiol increased the transcription of these genes about 2-3 fold. Among the Panaxadiol ginsenosides, the Rb2 subtraction appeared to is a major induce of SODI and catalase genes. Using the deletion analyses and mobility shift assays, we showed that the 5051 gene was greatly activated by ginsenoside Rba through transcription factor AP2 binding sites and its induction. We also examined the effect of the content ratio of panaxadiol extracted from various compartment of ginseng on the transcription of 5031 gene. Saponin extract that contains 2.6-fold more PD than PT from the fine root Increased the SODI induction about 3-fold. These results suggest that the panaxadiol fraction and its ginsenosides could induce the antioxidant enzymes, which are important for maintaining cell viability by lowering level of oxygen radical generated from intracellular metabolism.

• Journal of Microbiology and Biotechnology
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• 제17권9호
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• pp.1460-1468
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• 2007

In this study, an approx. 2.5-kb gene fragment including the catalase gene from Rhodospirillum rubrum S1 was cloned and characterized. The determination of the complete nucleotide sequence revealed that the cloned DNA fragment was organized into three open reading frames, designated as ORF1, catalase, and ORF3 in that order. The catalase gene consisted of 1,455 nucleotides and 484 amino acids, including the initiation and stop codons, and was located 326 bp upstream in the opposite direction of ORF1. The catalase was overproduced in Escherichia coli UM255, a catalase-deficient mutant, and then purified for the biochemical characterization of the enzyme. The purified catalase had an estimated molecular mass of 189 kDa, consisting of four identical subunits of 61 kDa. The enzyme exhibited activity over a broad pH range from pH 5.0 to pH 11.0 and temperature range from $20^{\circ}C$ to $60^{\circ}C$C. The catalase activity was inhibited by 3-amino-1,2,4-triazole, cyanide, azide, and hydroxylamine. The enzyme's $K_m$ value and $V_{max}$ of the catalase for $H_2O_2$ were 21.8 mM and 39,960 U/mg, respectively. Spectrophotometric analysis revealed that the ratio of $A_{406}$ to $A_{280}$ for the catalase was 0.97, indicating the presence of a ferric component. The absorption spectrum of catalase-4 exhibited a Soret band at 406 nm, which is typical of a heme-containing catalase. Treatment of the enzyme with dithionite did not alter the spectral shape and revealed no peroxidase activity. The combined results of the gene sequence and biochemical characterization proved that the catalase cloned from strain S1 in this study was a typical monofunctional catalase, which differed from the other types of catalases found in strain S1.

• Journal of Microbiology
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• 제38권1호
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• pp.18-23
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• 2000

Streptomyces coelicolor produces three kinds of catalases to cope with oxidative stress and to allow normal differentiation. Catalase A is the major vegetative catalase which functions in removing hydrogen peroxide generated during the process of aerobic metabolism. To understand the regulatory mechanism of response against oxidative stress, hydrogen peroxide-resistant mutant (HR4O) was isolated from S. coelicolor J1501 following UV mutagenesis. The mutant overproduced catalase A more than 50-fo1d compared with the wild type. The mutation locus catRI was mapped closed to the mthB2 locus by genetic crossings. An ordered cosmid library of S. coelicolor encompassing the mthB2 locus was used to isolate the regulator gene (catR) which represses catalase overproduction when introduced into HR4O. A candidate catR gene was found to encode a Fur-like protein of 138 amino acids (15319 Da).

• 대한수의학회지
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• 제31권2호
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• pp.167-170
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• 1991

The catalase phenotypes and the gene frequencies in erythrocyte of 223 Cheju native horses were studied by starch gel electrophoresis. The results obtained were as follows: 1. In the catalase phenotypes, three phenotypes, CatF, CatM and CatS, which were controlled by two allelic genes, $Cat^F$ and $Cat^S$, were observed and their frequencies of appearance were 24.21%, 47.53%, and 28.25% respectively. 2. The distribution of gene frequency was calculated as 0.480 in $Cat^F$ and 0.520 in $Cat^S$.

• Plant Biotechnology Reports
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• 제2권1호
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• pp.41-46
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• 2008

Salinity stress is a major limiting factor in cereal productivity. Many studies report improvements in salt tolerance using model plants, such as Arabidopsis thaliana or standard varieties of rice, e.g., the japonica rice cultivar Nipponbare. However, there are few reports on the enhancement of salt tolerance in local rice cultivars. In this work, we used the indica rice (Oryza sativa) cultivar BR5, which is a local cultivar in Bangladesh. To improve salt tolerance in BR5, we introduced the Escherichia coli catalase gene, katE. We integrated the katE gene into BR5 plants using an Agrobacterium tumefaciens-mediated method. The introduced katE gene was actively expressed in the transgenic BR5 rice plants, and catalase activity in $T_1$ and $T_2$ transgenic rice was approximately 150% higher than in nontransgenic plants. Under NaCl stress conditions, the transgenic rice plants exhibited high tolerance compared with nontransgenic rice plants. $T_2$ transgenic plants survived in a 200 mM NaCl solution for 2 weeks, whereas nontransgenic plants were scorched after 4 days soaking in the same NaCl solution. Our results indicate that the katE gene can confer salt tolerance to BR5 rice plants. Enhancement of salt tolerance in a local rice cultivar, such as BR5, will provide a powerful and useful tool for overcoming food shortage problems.

• 환경생물
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• 제29권1호
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• pp.61-67
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• 2011

NAC는 GSH의 전구물질로, thiol기를 포함하는 항산화제 중 하나로 잘 알려져 있으며, 방사선 조사 시 발생하는 생체 내 영향을 감소시켜 생체 손상의 방호 및 회복에 도움을 주는 방사선 방어제로 이용된다. S. cerevisiae에서 항산화제 NAC를 전처리 함에 따라 이온화 방사선 조사에 따른 효모의 세포사멸 방어효과 및 superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx)와 같은 항산화 효소들의 유전자 발현을 분석하여 NAC의 항산화적 효과를 확인하였다. 효모는 다양한 농도의 NAC 전처리 후 다양한 선량의 이온화 방사선에 조사되었으며, 세포생존율은 세포형성단위(CFU)를 계수해 측정되었고, 항산화 효소의 유전자 발현은 real-time PCR수행 후 분석하였다. 우선적으로 효모에 NAC 처리를 위한 적정농도를 확인하였는데, 35 mM 이상의 NAC 농도에서 효모세포의 성장이 억제 되었다. NAC 전처리는 감마선 조사에 의한 세포사멸을 방어하지 않았으며, 100 Gy 방사선 조사는 항산화 효소들의 유전자 발현을 유도하였다. NAC 전처리 후 항산화 효소들의 유전자 발현은NAC의 농도 증가에 따라 감소하였다. 이러한 결과로,NAC의 높은 농도(35 mM 이상)는 효모세포의 성장을 저해하며, NAC는 이온화 방사선 조사에 따른 세포사멸을 방어할 수 없으나, 생체 내에서 활성산소종을 제거 하여 세포를 보호하는 유용한 항산화제임을 알 수 있었다.

• BMB Reports
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• 제36권6호
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• pp.608-610
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• 2003

Escherichia coli has two catalases, HPI and HPII. HPI is induced during logarithmic growth in response to low concentrations of hydrogen peroxide. This induction is OxyR-dependent. On the other hand, HPII is not peroxide-inducible but is induced in entry to the stationary phase. We demonstrate here that E. coli displayed higher HPI catalase activity when compared to the cultures that were grown in a normal medium, if grown in a medium supplemented with iron-citrate. Iron supplementation had no effect on HPII catalase. This increase of HPI activity was OxyR-independent and not observed in a ${\Delta}fur$ mutant. The physiological significance of the increase of HPI activity is unclear, but it appears that the katG gene that codes for HPI catalase is among the genes that are regulated by Fur.

• Biomolecules & Therapeutics
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• 제27권2호
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• pp.134-144
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• 2019

The prevalence of nonalcoholic fatty liver disease (NAFLD) has increased with the incidence of obesity; however, the underlying mechanisms are unknown. In this study, high-resolution metabolomics (HRM) along with transcriptomics were applied on animal models to draw a mechanistic insight of NAFLD. Wild type (WT) and catalase knockout (CKO) mice were fed with normal fat diet (NFD) or high fat diet (HFD) to identify the changes in metabolic and transcriptomic profiles caused by catalase gene deletion in correspondence with HFD. Integrated omics analysis revealed that cholic acid and $3{\beta}$, $7{\alpha}$-dihydroxy-5-cholestenoate along with cyp7b1 gene involved in primary bile acid biosynthesis were strongly affected by HFD. The analysis also showed that CKO significantly changed all-trans-5,6-epoxy-retinoic acid or all-trans-4-hydroxy-retinoic acid and all-trans-4-oxo-retinoic acid along with cyp3a41b gene in retinol metabolism, and ${\alpha}/{\gamma}$-linolenic acid, eicosapentaenoic acid and thromboxane A2 along with ptgs1 and tbxas1 genes in linolenic acid metabolism. Our results suggest that dysregulated primary bile acid biosynthesis may contribute to liver steatohepatitis, while up-regulated retinol metabolism and linolenic acid metabolism may have contributed to oxidative stress and inflammatory phenomena in our NAFLD model created using CKO mice fed with HFD.