• Korean Journal of Microbiology
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• v.41 no.1
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• pp.87-92
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• 2005

Pronase, a protease produced for commercial purpose by Streptomyces griseus, was composed of serine protease, alkaline protease, aminopeptidase and carboxypeptidase complex, and it has been widely used as anti-inflammatory drugs for human therapy. In this study, we developed a new integration vector, pHJ101 derived from pSET152, containing strong promoter, ermE, to overexpress a certain protease gene. Specific PCR primers for cloning of sprA (a gene for S. griseus protease A) and sprB (a gene for S. griseus protease B) genes were designed from the basis of nucleotide sequence in databases and amplified by PCR. Plasmid pHJ201 and pHJ202 were constructed by inserting of amplified each gene in a vector pHJ101. S. griseus HA and S. griseus HB were respectively obtained by conjugal process of a parent strain, S. griseus IFO 13350 with the recombinant Escherichia coli harboring plasmid pHJ201 or pHJ202. When protease activity was measured in flask cultivation, produced protease levels of S. griseus HA and S. griseus HB increased about 5.3 times and 5 times, respectively, more than that of parent strain. And, the constructed integrating plasmid pHJ101 was applicable for overexpression of a certain gene in Streptomyces sp.

• YAKHAK HOEJI
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• v.48 no.6
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• pp.364-368
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• 2004

The prevalence of resistance to a range of macrolides was determined for clinical isolates of common respiratory pathogens using NCCLS testing methods and interpretative criter ia.71.4% of Streptococcus pneumoniae, 62.3% of Staphylococcus aureus, 50.8% of coagulase-negative staphylococci and 4.4% of Strpetococcus pyogenes were erythromycin resistant. Also, the rates of resistance to other macrolides and clindamycin in these clinical isolates were as high as to eryth -romycin. Almost all of the macrolide-resistant isolates were positive for erm of the methylase gene, or mef of the efflux gene.

• Proceedings of the Korean Society for Quality Management Conference
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• 2010.04a
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• pp.310-320
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• 2010

In this study, factors affecting the development of new products and research about the relevance of the factors based on the research model was configured. Existing research and technology commercialization process of discrimination that occur in the importance of risk management and open innovation company's competitive advantage in new product development and affect the reporter know what the effect is used as a control variable effects. Factor in the development of new products through research and innovation capacity and knowledge management activities, the introduction of open innovation and enterprise level ever due to the level of risk management controls and the need for effective research to study the model was proposed.

• Applied Chemistry for Engineering
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• v.17 no.2
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• pp.210-216
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• 2006

The concentrations of 16 priority PAHs (US EPA standard) were analyzed in the surface sediments obtained from 23 sampling sites near Kwangyang Bay in Korea. There was a local variability in the total PAHs ranged from 0.01 to 171.39 mg/kg, with a mean value of $8.13{\pm}24.8mg/kg$. The major pollution sources of PAHs near Kwanyang Bay were Taeindo, Sueo stream and Wallae stream, whose concentrations were 114.81, 38.37 mg/kg and 19.05 mg/kg, respectively. It showed that PAHs concentrations were increased with the decrease of particle size and with the increase of organic carbon contents in three fractioned sediments. From the analysis of PAHs source using LMW/HMW, Phe/Ant, and Fla/Pyr, pyrolysis by-products were mostly showed in Kwangyang Bay and some place showed the mixure of pyrolysis by-products, and crude oil by-products. Besides, the toxic effects assessment on benthic ecosystem for three major pollution sources showed that the PAHs concentration of Taindo which was mainly accumulated with carcinogenic PAHs exceeds ERM value and the PAHs of Sueo and Wallae streams are the degree of ERL value.

• YAKHAK HOEJI
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• v.50 no.3
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• pp.204-207
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• 2006

A total of 398 strains of Staphylococcus aureus (99), coagulase-negative staphylococci (CNS) (99), enterococci (100), Streptococcus pyogenes (18) and Streptococcus agalatiae (82) were in Korean tertiary hospital from Dec. 2004 to Mar, 2005. When minimal inhibitory concentrations (MIC), phenotypes and genotypes were determined, 70% of S. aureus, 65.7% of CNS, 78% of enterococci and 37.8% of S. agalatiae were resistant to erythromycin and 95.7% of erythromycin-resistant (EMR) S. aureus, 92.3% of EMR CNS and all of EMR enterococci and S. agalatiae had erm of the methylase gene or msr(A) of the efflux gene.

• Journal of Microbiology and Biotechnology
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• v.16 no.2
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• pp.295-298
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• 2006

Actinomycetes are ubiquitous Gram-positive soil bacteria and a group of the most important industrial microorganisms for the biosynthesis of many valuable secondary metabolites as well as the source of various bioconversion enzymes. Cytochrome P450 hydroxylase (CYP), a hemebinding protein, is known to be involved in the modification of various natural compounds, including polyketides, fatty acids, steroids, and some aromatic compounds. Previously, six different novel CYP genes were isolated from a rare actinomycetes called Sebekia benihana, and they were completely sequenced, revealing significant amino acid similarities to previously known CYP genes involved in Streptomyces secondary metabolism. In the present study, these six CYP genes were functionally expressed in Streptomyces lividans, using an $ermE^{*}$ promoter-containing Streptomyces expression vector. Among six CYP genes, two S. benihana CYP genes (CYP503 and CYP504) showed strong hydroxylation activities toward 7-ethoxycoumarin. Furthermore, the recombinant S. lividans containing both the S. benihana CYP506-ferredoxin genes as well as the S. coelicolor feredoxin reductase gene also demonstrated cyclosporin A hydroxylation activity, suggesting potential application of actinomycetes CYPs for the biocatalysts of natural product bioconversion.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.52-58
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• 2014

Structurally, herboxidiene contains the tetrahydropyran acetic acid moiety and a side chain including a conjugated diene, and has been isolated from Streptomyces chromofuscus ATCC 49982. Its production was significantly elevated nearly 13.5-fold (0.74 g/l) in a medium supplemented with glycerol (medium No. 6A6), and was more efficacious (1.08 g/l; 19.8-fold) in fed-batch fermentation at 36 h in medium No. 6A6, from Streptomyces chromofuscus. For further enhancement, regulatory genes metK1-sp and afsR-sp from Streptomyces peucetius were overexpressed using an expression vector, pIBR25, and similarly ACCase from Streptomyces coelicolor and two genes, metK1-sp and afsR-sp, were also overexpressed using an integration vector, pSET152, under the control of the strong $ermE^*$ promoter in Streptomyces chromofuscus. Only the recombinant strains S. chromofuscus SIBR, S. chromofuscus GIBR, and S. chromofuscus AFS produced more herboxidiene than the parental strain in optimized medium No. 6A6 with an increment of 1.32-fold (0.976 g/l), 3.85-fold (2.849 g/l), and 1.7-fold(1.258 g/l) respectively.

• Journal of Information Technology Services
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• v.14 no.3
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• pp.117-129
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• 2015

For the continuous growth of firms, the contributions of effective risk management system are required. This research analyzes the impact on the firm's performance related to risk management structure which includes the risk management system, risk management activity and risk management competency. In this research, the structural equation model considering the variable which contains enterprise risk management system, risk management activity and risk management competency was suggested. Also risk management organization and management procedures are identified as in enterprise risk management system. The implementation activity and control activity were the factors related in risk management activity. And risk management competency can be described as the response level of managing risk in outside and inside the firms' environment. Finally this model was analysed empirically for 112 firms in Korea using SPSS 18.0 and Amos 16.0. As the results, the suggested hypothesis were adopted. So as to manage risk performance for their firms, the development of systematic Risk Management Framework is important for their risk management activity and risk management competency. Ultimately, we can conclude that the focusing to the systematic risk management approach could be effective on the firm's risk management performance.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.148-151
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• 2010

The aim of this study was to investigate the erythromycin resistance patterns of Enterococci sp. present in cow milk. A total 110 erythromycin resistant Enterococci were isolated from milk samples; E. faecalis (n=101), E. avium (n=7), and E. durans (n=2). The minimum inhibitory concentration of erythromycin against 110 Enterococci were determined. The 66.3% of Entercocci (n=73) showed high level resistance (${\geq}64$ mg/ml). Among 110 isolates, 86.3% (n=95) showed $cMLS_B$ phenotype and 13.6% (n=15) showed $iMLS_B$ The aim of this study was to investigate the erythromycin resistance patterns of Enterococci sp. present in cow milk. A total 110 erythromycin resistant Enterococci were isolated from milk samples; E. faecalis (n=101), E. avium (n=7), and E. durans (n=2). The minimum inhibitory concentration of erythromycin against 110 Enterococci were determined. The 66.3% of Entercocci (n=73) showed high level resistance (${\geq}64$ mg/ml). Among 110 isolates, 86.3% (n=95) showed $cMLS_B$ phenotype and 13.6% (n=15) showed $iMLS_B$ phenotype. All of isolates have erm(B) determinant, 75.45% (n=83) have mef(A) an efflux system determinant. The majority of Enetrcococci isolated from raw milk samples in northern area of Gyeonggi-Do showed high level of resistance to erythromycin.

• Clinical and Experimental Pediatrics
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• v.51 no.10
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• pp.1031-1037
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• 2008

Macrolide antimicrobial agents including erythromycin, roxithromycin, clarithromycin, and azithromycin are commonly used in the treatment of respiratory tract infections in children. Newer macrolides that have structural modifications of older drug erythromycin show improved change in the spectrum of activity, dosing, and administration. However, recent studies reported that increasing use of macrolide antibiotics is the main force driving the development of macrolide resistance in streptococci. In particular, azithromycin use is more likely to select for macrolide resistance with Streptococcus pneumoniae than is clarithromycin use, a possible reflection of its much longer half life. Recently, erythromycin resistance rates of S. pneumoniae and Streptococcus pyogenes are rapidly increasing in Korea. Two main mechanisms of acquired macrolide resistance have been described, altered binding site on the bacterial ribosome encoded by the ermB gene and active macrolide efflux pump encoded by the mef gene. Relationship between the susceptibility of S. pneumoniae and the response to macrolides has been shown in studies of acute otitis media, but less clear in cases of pneumonia. This article reviews the spectrum of activity, pharmacokinetic properties, mechanisms of action and resistance, and clinical implication of resistance on the treatment of respiratory tract infections in children.