• Korean Journal of Microbiology
• /
• v.30 no.4
• /
• pp.291-298
• /
• 1992

Srrepromycec. corlirolar produces at least 4 catalase activity bands with different electrophoretic mobilities on polyacrylamide gel which vary during development. Spores and mycelia at stationary phase produced all the activity bands(Cat1. 760 kr); Cat3-I, 170 kD: Cat3-2, 140 kD: Cat3-3. 130 kD; Cat4, 70 kD) except for Cat2 (300 kD). Mycelia at mid-logarithmic phase produced only Cat2 and Cat3-2 bands, and mycelia at late-logarithmic phase produced bands except Catl and Cat\ulcorner. Catalase-deficient mutants were screened in S. coelicalur by H201 bubbling test following NTG mutagenesis. Wc tested sevcral non-bubbling or slow-bubbling mutants for their catalase activities. The overall activities in cell extracts decreased more than 5 fold. Activity bands in native gel selectively decreased in intensity or disappeared. In all the non-bubbling mutants testcd, Cat3-2 band decreased significantly or disappeared. suggesting that Cat3-2 is the major catalase. The selective disappearance of bands in mutants suggest that each band is governed by different genes. We purified catalase activity from -:ell extracts obtained at late-logarithmic phase. Following chromatographies on Sepharose CL-4B. DEAE Sepharose CL-6B. Phcnyl Sepharose CL-4B. and hydroxylapatite columns. only the Cat3-2 activity was obtained. The native form of Cat3-2 has molecular weight of approximately 140 kD, judged by gel electrophoresis. Thc electrophoretic mobility on SDS-polyactylamide gel suggests that this enzyme contains 2 identical subunits of 67 kD.

• Molecules and Cells
• /
• v.20 no.2
• /
• pp.247-255
• /
• 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.

• Korean Journal of Microbiology
• /
• v.32 no.2
• /
• pp.155-162
• /
• 1994

Cells of Acinetobacter sp. strain JC1 DSM 3803, an aerobic monoxide-oxidizing bacterium, growing on glucose exhibited high catalase activity at the mid-exponential growth phase. The enzyme activity decreased gradually after then until the early stationary phase, increased again at the mid-stationary phase, and then decreased again thereafter. Cells growing on glucose was found to contain three kinds of catalses. Cat1, Cat2 and Cat3. The activities of Cat1 and Cat3 did change significantly during growth, but that of Cat2 exhibited significant variation. Cat3 was found to present only in cells growing on glucose, but not in cells growing on carbon monoxide of methanol. The activities of call and Cat3 in cell-free extracts were stable upon treatment with ethanol and chloroform, but decreased to some extent when the enzymewere treated with 2mM $H_2O_2$ and/or 3-amino-1,2,4-triazole (AT). Cat2 was found to be extremely sensitive to the ethanol-chloroform and $H_2O_2$ treatments, but was insensitive to the AT treatment. Cat1 exhibited enzyme activity after incubation for 1 min at 80$^{\circ}C$. Cat2 and Cat3 did not show enzyme activity after incubation for 1 min at 60$^{\circ}C$ and 70$^{\circ}C$, respectively. Cat2 was found to have peroxidase activity. Cat3 was purified to homogenity in seven steps. The molecular weight of the native enzyme was estimated to be 150,000. Sodium dodecyl sulfate-gel electrophoresis revealed two identical subunits of molecular weight 65,000. The enzyme was found to show two $K_m$ values of 39 mM and 58mM. The optimal pH for the enzyme activity was 7.0, but the activities at pH 6.0, 8.0, and 9.0, were found to be comparable to that at the optimal pH. The optimal temperature for the enzyme activity was found to be 40$^{\circ}C$. The enzyme also exhibited strong activity at 20$^{\circ}C$, 30$^{\circ}C$, and 50$^{\circ}C$. The purified enzyme was not affected by the ethanol-chloroform treatment. The enzyme, howerver, showed less than 10% of the original activity when it was treated with 12 mN AT, 0.1 mM $NaN_3$ of 1mM KCN.

• Journal of Microbiology
• /
• v.39 no.3
• /
• pp.168-176
• /
• 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.

• Archives of Pharmacal Research
• /
• v.20 no.5
• /
• pp.404-409
• /
• 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.

• Journal of the Semiconductor & Display Technology
• /
• v.21 no.3
• /
• pp.26-32
• /
• 2022

EtherCAT is an Ethernet-based fieldbus system standardized in IEC 61158 and SEMI, and widely used in the fields of factory automation, semiconductor equipment and robotics. In this paper, an EtherCAT master is implemented on an embedded board with Arm based 64-bit quad-core processor and its jitter performance is evaluated at the output of the network interface to include all the effects of the entire system in the results. For the EtherCAT master system, an open source EtherCAT master stack, Simple Open EtherCAT Master (SOEM), is installed on PREEMPT_RT patched Linux operating system for real-time operation. The results show that the jitter performance is comparable to that of Xenomai-based master and the EtherCAT master with two master instances has similar jitter performance to the EtherCAT master with one master instance.

• Journal of the Semiconductor & Display Technology
• /
• v.20 no.2
• /
• pp.131-136
• /
• 2021

EtherCAT is an Ethernet-based fieldbus system standardized in IEC 61158 and SEMI, and widely used in the fields of factory automation, semiconductor equipment and robotics. In this paper, a real-time EtherCAT master is implemented on Linux operating systems and its performances are evaluated. To enhance the real-time capability of mainline Linux kernel, Xenomai is applied as a real-time framework and an open source EtherCAT master stack, Simple Open EtherCAT Master (SOEM), is installed on it. Unlike other studies, the real-time performance of the EtherCAT master is evaluated at the output of the network interface card, so that the evaluation results include all possible effects from the EtherCAT master system. The implemented EtherCAT master can send and receive packets up to 20KHz control frequency with low jitter, even in stressed condition.

• Journal of Korean Academy of Fundamentals of Nursing
• /
• v.13 no.3
• /
• pp.457-466
• /
• 2006

Purpose: This study was done to investigate oncology nurses' perception, attitude, knowledge and practice of CAT and to describe nurses' needs for education on CAT Method: A cross-sectional descriptive study was conducted. A total of 270 oncology nurses working at four medical centers in Seoul and Kyungki participated in this study. They completed the questionnaire between December 2005 and February 2006. Results: Oncology nurses perceived CAT as possible nursing interventions, but felt that there was no conclusive evidence on effectiveness/safety. Of the participants 44.4% have used CAT for themselves, and 73.9% of them were satisfied after using CAT. Two biggest reasons for CAT use were symptom control and emotional support. However, 80.8% of the participants had not had any training related to CAT Both nurses who have used CAT and those who have been trained to practice CAT represented a more positive perception toward CAT (p=.000). The biggest perceived obstacles to the practice of CAT were concerns about side effects (71.2%) and lack of knowledge and skill (69.6%). The most favorable CAT modalities in both practice and training were mind-body medicine. Conclusion: Overall oncology nurses' perception toward CAT was encouraging. However a high number of the nurses reported lack of knowledge and skill in CAT Education and training strategy for CAT need to be developed.

• Journal of Aquaculture
• /
• v.10 no.4
• /
• pp.409-415
• /
• 1997

The carp $\beta$-actin regulatory sequences and RSV/LTR promoter were tested whether they are functinal to express linked structure gene (chloramphenicol acetyltransferas, CAT) in olive flounder (Paralichthys olivaceus) by determining the patterns of gene expression following intramuscular in vivo direct injection. The injection experiments with various concentrations of both pRSVCAT and pFV4CAT clearly revealed the effectiveness of DNA dosage on expression of CAT. The increase of CAT activity was linear in both plasmids, and maximal CAT activity was obtained with 100 ug of pFV4CAT injection. The amounts of CAT expression with pFV4CAT-injected fist were higher than those with pRSVCAT-injected fish. CAT activity was readily detectable as early as one day after injection, slightly increased at day 2, and declined over time. Most amount of DNA intramuscularly injected into olive flounder muscles persisted extrachromosomally without showing any integrated or replicated form in vivo.

• Journal of Microbiology and Biotechnology
• /
• v.31 no.2
• /
• pp.259-271
• /
• 2021

Many bacteria metabolize aromatic compounds via catechol as a catabolic intermediate, and possess multiple genes or clusters encoding catechol-cleavage enzymes. The presence of multiple isozyme-encoding genes is a widespread phenomenon that seems to give the carrying strains a selective advantage in the natural environment over those with only a single copy. In the naphthalene-degrading strain Pseudomonas putida ND6, catechol can be converted into intermediates of the tricarboxylic acid cycle via either the ortho- or meta-cleavage pathways. In this study, we demonstrated that the catechol ortho-cleavage pathway genes (catBICIAI and catBIICIIAII) on the chromosome play an important role. The catI and catII operons are co-transcribed, whereas catAI and catAII are under independent transcriptional regulation. We examined the binding of regulatory proteins to promoters. In the presence of cis-cis-muconate, a well-studied inducer of the cat gene cluster, CatRI and CatRII occupy an additional downstream site, designated as the activation binding site. Notably, CatRI binds to both the catI and catII promoters with high affinity, while CatRII binds weakly. This is likely caused by a T to G mutation in the G/T-N11-A motif. Specifically, we found that CatRI and CatRII regulate catBICIAI and catBIICIIAII in a cooperative manner, which provides new insights into naphthalene degradation.