• 한국미생물·생명공학회지
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• 제24권6호
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• pp.657-663
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• 1996

Pseudomonas sp. P20 isolated from the polluted environment is capable of degrading biphenyl and 4-chlorobiphenyl. The pcbABCD genes responsible for degradation of biphenyl and 4-chlorobiphenyl were cloned using pBluescript SK(+) from the chromosomal DNA of Pseudomonas sp. P20 to construct pCK1 and pCK102, harbouring pcbABCD and pcbCD, respectively. The 2, 3-DHBP dioxygenase gene, pcbC, was cloned again from pCK102 by using pKT230 which is known as a shuttle vector and pKK1 hybrid plasmid was constructed. The E. coli KK1 transformant obtained by transforming the pKK1 into E. coli XL1-Blue showed 2, 3-DHBP dioxygenase activity. The specific 2, 3-DHBP dioxygenase activity of E. coli KK1 was similar to that of the E. coli CK102, but much higher than those of the natural isolates, Pseudomonas sp. DJ-12 and Pseudomonas sp. P20.

• 한국미생물·생명공학회지
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• 제23권2호
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• pp.145-149
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• 1995

For the purpose of developing a new biodegradable detergent, we have isolated a gene encoding wide-range temperature applicable alkaline protease from Xanthomonas sp. YL-37 (Lee et al., 1994, Kor. J. Appl. Microbiol. Biotechnol.). An alkaline protease gene was isolated from the gene bank that was prepared from the chromosomal DNA of Xanthomonas sp. YL-37. From the results of agarose gel electrophoresis and a restriction enzyme mapping, a 2.7 kb DNA fragment containing the alkaline protease gene was inserted in the plasmid pUC9. Extracellular activity of a clone having alkaline protease gene was detected on SDS-polyacrylamide gel with activity staining assay. The molecular weight of alkaline protease was determined to be about 64 kDa from 11% SDS-PAGE analysis. Alkaline protease activity, produced from E. coli which harboring the plasmid, showed no difference at reaction temperature 20, 30 and 40$\circ$C, respectively. This result showed that alkaline protease produced from E. coli harboring the plasmid was apparently the same as that of Xanthomonas sp. YL-37.

• 산업기술연구
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• 제37권1호
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• pp.16-20
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• 2017

A new putative laccase gene (soncotA) which show 78% homology with that from Bacillus licheniformis (liccotA) was isolated from draft genome sequence of Bacillus sonorensis KCTC 13918. A 1,545 bp of PCR product corresponding 514 amino acids was cloned into NdeI-NotI site of pET21c and expressed as soluble form in E. coli. About 59 kDa size of recombinant laccase was purified into homogenity by Ni-NTA column and laccase activity was confirmed by zymography. The enzymatic properties of recombinant laccase were characterized. The specific activity of B. sonorensis laccase was 0.033 fold lower than that of Bacillus licheniformis laccase. The finding of new laccase gene broadened the enzymatic diversity of Bacillus species laccases.

• 약학회지
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• 제37권5호
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• pp.504-510
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• 1993

Human insulin gene is consisted of the polymorphic region with the repeating units, the regulatory sequence, the structural gene including the intervening sequence, and 3'-flanking region. The polymerase chain reaction, which amplifies the target DNA between two specific primers, has been performed for the amplification of human insulin gene and simple one-step cloning of it into Escherichia coli. Out of 1727 nuceotides compared, only 4 sites were variable: 5'-regulatory region(G2101$\rightarrow$AGG); IVS I(T2401$\rightarrow$A); Exon II(C2411 deletion); IVS II(A2740 dejection). The variations at the G2101 and T2401 were the same as those found in one American allele. The other two variations were observed only in the specific Korean allele. And, the enzyme digestion patterns among normal, insulin dependent diabetes mellitus, and non-insulin dependent diabetes mellitus were the same. On the other hand, PCR method showed the possibility of the quickaccess for the polymorphic region in terms of the restriction fragment length of polymorphism.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2004년도 제34차 추계 국제 학술대회
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• pp.388-390
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• 2004

본 연구는 자돈 설사의 원인이 되는 대장균, 살모넬라 등 그람음성균을 억제할 수 있는 유산균의 이용을 위해 선발된 균주의 과산화수소 대사를 구명하기 위해 수행하였다. 대장균 억제유산균중 superoxide dismutase 활성이 우수한 균주가 관찰되었으며, 과산화수소 이외에 그람음성균 억제에 유효한 bacteriocin-like compounds의 존재 유무, 대사과정에서 과산화수소 생성과 관련된 다른 효소 활성, superoxide dismutase 유전자 클로닝에 관한 연구가 진행중이다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.180-183
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• 2002

Pseudomonns putida BCNU171 had the tolerant ability to several other organic solvents headed by toluene and xylene. Several mutants were made by mating of BCNUl71, pJFF350 to clarify the structure tolerance gene related. From this mutants the 7 of mutants related with toluene sensitive mutants were selected. pBCNUT-2, pBCNUT-4, pBCNUT-9 was transformed, and from this separated plasmid DNA sequences the gene having high homology was searched. In the case of toluene sensitive mutant it was todX gene (pBCNU4) related with cell membrane, ttgE gene (pBCNU2, pBCNU9) and ttgF gene (pBCNU2, pBCNU9).

• 한국수산과학회지
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• 제36권5호
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• pp.442-448
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• 2003

Melanin concentrating hormone (MCH) regulating color change of fish skin was identified from brain cDNA library of Olive flounder (Paralichthys olivaceus) during the analysis of Expressed Sequence Tags (ESTs). Olive flounder MCH gene consisted of 598 nucleotides encoding 150 amino acids. Olive flounder MCH protein revealed to contain signal peptide of 19 amino acid residues, pro-MCH of 131 amino acids being processed to biologically active and mature form of hormone with 25 amino acid residues at the carboxyl terminus. A comparative structural analysis revealed that Olive flounder MCH precursor had low sequence identity with other fish species and mammalian counterparts, while the amino acid sequences of mature hormone had a relatively high identity and more conserved. RT-PCR analysis revealed that olive flounder MCH precersor gene was expressed spectically only in the brain and not in other tissues.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.593-598
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• 1994

A bacterium KL-57 which exhibited biosurfactant activity was isolated. This bacterium was identified as Bacillus subtilis. The biosurfactant-producing gene of B. subtilis KL-57 was cloned into R subtilis MI113 by using plasmid pTB523. The plasmid DNA from the clone was found to carry a 18 kb PstI insert. The biosurfactant-producing gene was cleaved into 4 fragments by SmaI, 3 fragments by PvulI or EcoRl, 4 fragments by PvulI and EcoRI double digestion, 5 fragments by AccI, and 2 fragments by KpnI, HindIII or BamHI. By subcloning the 18 kb Pstl insert, a 2.3 kb EcoRl fragment conferred the biosurfactant producing activity on B. subtilis cells. The 2.3 kb had one HindIII cleave site. But Two fragments, which corresponds HindIII/EcoRl termini, exhibited no biosurfactant activity.

• 한국미생물·생명공학회지
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• 제22권6호
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• pp.599-606
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• 1994

Bacillus stearothermomophilus, a strong xylan degrader, was confirmed to express multiple esterase activities in addition to the major xylanolytic enzymes. One of the genes encoding the esterases was isolated from the genomic library of B. stearothermophilus constructed with EcoRl restriction endonuclease and pBR322 plasmid. Three recombinant plasmids showing the tributyrin degrading activity were selected from approximately 7, 000 E. coli HB101 transformants, and were found to have the same insert of a 3.2 kb DNA fragment. Restriction mapping and hybridization studies revealed that the gene(estII) on the hybrid plasmid (pKMG7) had originated from the B. stearothermophilus chromosome, and was distinct from the estl, another esterase gene of B. stearothermophilus isolated in the previous work. The E. coli cells harboring pKMG7 produced an acetylxylan esterase that exibited similar substrate specificity to the esterase encoded by the estI gene.

• 한국연초학회지
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• 제25권2호
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• pp.87-94
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• 2003

Recently, many researches for plant alkaloids, one of the largest groups of natural products, are reported because of their various pharmacological activity. This study was carried out to clone putrescine N-methyltransferase (PMT) gene which is a key enzyme in diverting polyamine metabolism towards the biosynthesis of nicotine and related alkaloids from Burley tobacco. To induce expression of PMT gene in tobacco plant, the floral meristem was removed and then mRNA was purified from root. cDNA encoding PMT gene was isolated by RT PCR and cloned. Three different groups of clones were screened by PCR and restriction enzyme digestion analysis and were characterized. The data of these screening revealed that three types of PMT are present in Burley tobacco. Comparison of the nucleotide sequence of this three genes encoding putative PMT with those of other tobaccos revealed that two types of PMT are newly discovered from Nicotiana tabacum cv. Br21 tobacco and they were same as PMT2, PMT3 of N. tabacum cv. Xanthi.