• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.10a
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• pp.592-592
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• 2007

• Proceedings of the Korean Society of Grassland Science Conference
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• 1999.06a
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• pp.74-74
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• 1999

Bentgrass의 형질전환식물 생산을 위하여 유전자총 (Gene-gun) 및 Agrobacterium기법을 이용하여 형질전환을 시도한 결과를 요약하면 다음과 같다. 1. 캘러스의 유도 및 증식 : Bentgrass (Agrostis palustris)의 종자를 MS-5 배지 (MS 기본배지, 2,4-D 5mg/L, casein hydrolysate 2g 포함)에 치상하여 캘러스를 유도하였다. 유도된 캘러스는 증식을 위하여 MS-3 배지 (MS기본배지, 2,4-D 3mg/L, casein hydrolysate 2g 포함)에서 2주 간격으로 subculture 하였다.(중략)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.174.2-174.2
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• 2003

Quorum sensing, a gene expression in response to population density, is regulated by chemical signals, most of which are acylated homoserine lactones (AHLs). The AHL derivatives have been reported to regulate bioluminescence, virulence factors and / or swarming motility in bacteria. It is hypothesized that higher organisms may have evolved specific means to interfere with bacterial communication as exemplified in the AHL-antagonistic activity of halogenated furanones isolated from the Australian macroalga Delisea pulchra. (omitted)

• Journal of Microbiology and Biotechnology
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• v.7 no.5
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• pp.293-298
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• 1997

A 4.6-kb HindIII fragment encompassing the complete 140-kDa ${\alpha}$-amylase gene of Lactobacillus amylovorus B 4540 was cloned into pBR322 by the shot gun method. Southern blotting and restriction mapping for the insert were performed. The recombinant 9.0-kb plasmid, pFML1, conferred ${\alpha}$-amylase activity to E. coli and Lactococcus lactis hosts when introduced by electroporation. SDS-PAGE and zymography confirmed the production of 140-kDa ${\alpha}$-amylase and its proteolytic degradation products with enzyme activity in transformants. Total ${\alpha}$-amylase activity of E. coli $DH5{\alpha}$ cells harboring pFML1 was 1.8 units and most activity was detected from cell pellets. Total enzyme activity of L. lactis subsp. lactis MG1363 transformant was five to ten-fold lower than that of E. coli cell but more than half of the activity was detected in the culture supernatant.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.420-422
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• 2005

TMC (Tautomycetin) is a liner polyketide immunosuppressive antifungal compound produced by Streptomyces spp. Inhibition of T cell proliferation with TMC was observed highly efficient at 100-fold lower than those needed to achieve maximal inhibition with cyclosporin A. To elucidate the biosynthetic pathway of TMC, a genomic DNA library was constructed using a E. coil-Streptomyces shuttle cosmid vector, pOJ446. The DNA libraries were screened by colony blot hybridization using several polyketide ${\beta}-ketosynthase$ (KS) probes amplified from TMC-producing Streptomyces genomic DNA using polymerase chain reaction (PCR), of which the degenerate primers were designed based on the highly conserved sequences present in KS domains of various type I polyketide synthase genes in Streptomyces species. This library construction and screening approach led to the isolation of several positive cosmid clones representing type I polyketide biosynthetic gene clusters. In addition, a Streptomyces regulatory gene called afsR2 (a global regulatory gene stimulating antibiotic production in both S. coelicolor and S. lividans) was successfully integrated into the TMC-producing Streptomyces chromosome via E. coil-Streptomyces heterologous conjugation mehtod. The more detailed results of production improvement and genetic characterization of TMC-producing Streptomyces spp. will be discussed.

• Biomedical Science Letters
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• v.18 no.2
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• pp.152-159
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• 2012

Campylobacter species are known to the high optimum growth temperature ($42^{\circ}C$) and the cause of enteritis in people. Erythromycin has a curative effect for enteritis caused by the bacteria. However, the rate of erythromycin-resistant bacteria was not well known until recently in Korea. Swine are one of sources of the infection with a Campylobacter species which cause the symptom of a high temperature. In this study, we cultured rectum fecal specimens of 100 pigs in an area of Buan-gun, Jeonbuk Province during July 2009. As a result, the detection rate of C. jejuni and C. coli and the rate of erythromycin-resistant bacteria for the separated Campylobacter species on the condition of high temperature were investigated. The possession or not of hipO and glyA gene and ciprofloxacin-resistant gene gyrA was also reviewed with biochemical characteristics and PCR.

• Parasites, Hosts and Diseases
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• v.39 no.2
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• pp.143-150
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• 2001

The present study was designed to investigate polymorphism in Duffy binding protein (DBP) gene of Plasmodium vivax isolates of Korea. Thirty samples were obtained from P. vivax patients in Yonchon-gun, Kyonggi-do in 1998. The PCR products of the samples were subjected to sequencing and hybridization analyses of the regions II and IV of P. vivax DBP gene. Two genotypes, SK-1 and SK-2, were identified on the basis of amino acid substitution and deletion. The genotype of 10 isolates was SK-1 and that of 20 isolates was SK-2. Most of the predicted amino acids in the region ll of DBP gene were conserved between the Korean isolates and Belem strain except for 4-5 amino acid substitutions. In the region W of DBP, a 6-bp insert that was shown in the Sal-1 allele type was found in SK-1, and a 27-bp insert that was shown in the Papua New Guinea allele type was found in SK-2. In conclusion, the present findings suggest that two genotypes of P. vivax coexist in the endemic area of Korea.

• Journal of Microbiology and Biotechnology
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• v.17 no.6
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• pp.1018-1023
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• 2007

Bacillus subtilis CH3-5 was isolated from cheonggukjang prepared according to traditional methods. CH3-5 secreted at least four different fibrinolytic proteases (63, 47, 29, and 20 kDa) into the culture medium. A fibrinolytic enzyme gene, aprE2, encoding a 29kDa enzyme was cloned from the genomic DNA of CH3-5, and the DNA sequence determined. aprE2 was overexpressed in heterologous B. subtilis strains deficient in extracellular proteases using a E. coli-Bacillus shuttle vector. A 29 kDa AprE2 band was observed and AprE2 seemed to exhibit higher activities towards fibrin rather than casein.

• Microbiology and Biotechnology Letters
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• v.46 no.2
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• pp.114-119
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• 2018

Astaxanthin is one of the major carotenoids used in pigment has a great economical value in pharmaceutical markets, feeding, nutraceutical and food industries. This study was to increase the production of astaxanthin by co-expression with transformed Escherichia coli using six genes involved in the non-mevalonate pathway. Involved in the non-mevalonate biosynthetic pathway of the strain Kocuria gwangalliensis were cloned dxs, ispC, ispD, ispE, ispF, ispG, ispH and idi genes in order to increase astaxanthin production from the transformed E. coli. And co-expression with the genes to compared the amount of astaxanthin production. This engineered E. coli, containing both the non-mevalonate pathway gene and the astaxanthin biosynthesis gene cluster, produced astaxanthin at $1,100{\mu}g/g$ DCW (dry cell weight), resulting in approximately three times the production of astaxanthin.

• Preventive Nutrition and Food Science
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• v.13 no.3
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• pp.190-195
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• 2008

The $\alpha$-amylase gene, amyL, from Bacillus licheniformis was expressed in Lactobacillus brevis 2.14 and Escherichia coli $DH5{\alpha}$ using two different shuttle vectors, pCW4 and pSJE. E. coli transformants (TFs) harboring either $pCW4T{\alpha}$ or $pSJET{\alpha}$ produced active $\alpha$-amylase but L. brevis TFs did not, as determined by enzyme assays and zymography. But amyL transcripts were synthesized in L. brevis TFs. In terms of plasmid stability, pSJE, a theta-type replicon, was more stable than pCW4, an RCR (rolling circle replication) plasmid, in L. brevis without antibiotic selection.