• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2004년도 춘계학술발표대회
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• pp.193-193
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• 2004

Gene targeting is an in situ manipulation of endogenous gene with precise manner by the introduction of exogenous DNA. The process of gene targeting involves a homologous recombination reaction between the targeted genomic sequence and an exogenous targeting vector. In elucidating the function of many genes, gene targeting has become the most important method of choice. (omitted)

• 미생물학회지
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• 제28권3호
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• pp.192-198
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• 1990

플라스미드 pKM101과 이의 돌연변이제 pSLA의 mutator 유전자를 subcloning하여 재조합 플라스미드 pJB200과 pJB210을 선별하였고, umuC36- uvrA6-(TK 610) 균주에 도입하여 UV와 MMS에 대해서 보호효과와 돌연변이율에 미치는 영향을 조사하였다. 재조합된 플라스마드는 UV와 MMS에 대해서 nonmutability인 umu- 균주에서 완전히 돌연변이율을 회복시켰고 보호효과를 크게 증가시켰다. 이 사실은 muc 유전자가 cloning된 재조합 플라스미드가 돌연변이원의 처리에 의해 효과적인 발현을 하며, muc 유전자 만으로도 pKM101의 기능을 나타낸다는 것을 확인하였고, pSLA의 muc 유전자가 그 효과에 었어서 높은 영향을 미쳤다. 또한 pKM101의 muc gene을 포함한 pJB210 은 recA - (JC2926) 균주에서 돌연변이 유발능에 영향을 미치지 못한 것은 muc 유전자가 recA 유전자에 의존함을 알 수 있었다.

• 한국미생물·생명공학회지
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• 제39권1호
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• pp.70-76
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• 2011

Weissella 속 유산균 검출의 차이를 이용한 한국산 및 중국산 김치 판별의 가능성 검토를 위하여 Weissella 속 9종 균주의 PCR 검출법을 개발하였다. 종(species) 수준에서의 Weissella 속 균주의 특이적 PCR 검출을 위한 primer는 recN 유전자의 염기서열을 이용하여 선정하였으며, 김치로부터 W. cibaria, W. confusa, W. koreensis, W. soli를 모두 검출하기 위해서는 20 ng template DNA가 필요한 것으로 나타났다. 한국산 김치시료로부터는 W. cibaria, W. confusa, W. koreensis가 높은 빈도로 검출되었지만, W. soli는 검출되지 않았다. 한편 중국산 김치시료로부터는 이들 4종의 Weissella 속 균주들이 모두 검출되었다. 본 연구자들이 개발한 W. soli 특이적 PCR 검출은 현시점에서 중국산 김치의 원산지 판별법으로 적용되기에는 한계점을 가지고 있지만, 미생물 군집의 차이를 이용한 새로운 과학적 검증법이 제시되어 그 가능성이 검토되었다는 점에서 의의를 가지고 있다.

• 미생물학회지
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• 제22권3호
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• pp.183-189
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• 1984

In order to find specific acting site of Rec A protein in plasmic polymerization in E. coli, we randomly deleted various part of pEC-3 (a derivative of pBR322) with SI nuclease treatment. Self-ligated plasmids were introduced into E. coli WA802(Rec $A^+$). A number of colonies were analyzed if they contained monomeric or polymeric plasmids by gel electrophoresis. The plasmid (pEC-43), which was deleted the region of tetracycline gene, revealed only monomeric form in Rec $A^+$ E. coli. When two plasmids, pEC-3 and pEC-43, were co-transformed in the same E. coli, the original pEC-3 showed polymerization but pEC-43 revealed monomeric form only. These results suggest that Rec A protein requires the specific site for polymerization.

• 한국미생물·생명공학회지
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• 제36권2호
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• pp.96-100
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• 2008

recA 유전자를 특이적으로 증폭하는 PCR을 이용하여 우리나라 전통 침채류 발효에 관여하는 유산균의 다양성을 검토해 보았다. 김치에서 많이 검출되는 유산균 7종 및 대조군으로 Lactobacillus acidophilus를 검출할 수 있는 특이적 PCR primer pair을 이용하여 전통 침채류 5증(갓김치, 동치미, 배추김치, 오이소박이, 총각김치로부터 추출한 DNA를 template로 PCR을 수행한 결과, 5종의 침채류 모두에서 Lactobacillus plantarum과 Lactobacillus sakei가 검출되었지만, Lactobacillus paraplantarum, Lactobacillus pentosus와 대조군인 Lb. acidophilus는 검출되지 않았다. Lactobacillus brevis와 Leuconostoc citreum은 배추김치에서만 검출되었으며, Leuconostoc mesenteroides의 경우 갓김치, 동치미, 배추김치, 오이소박이에서 검출되었다. 주재료의 종류에 따라서 발효에 관여하는 유산균은 차이가 있는 것으로 추정되며, Lb. plantarum과 Lb. sakei가 우리나라 침채류 발효에 가장 널리 관여하는 것으로 사료된다.

• 생약학회지
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• 제34권1호통권132호
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• pp.80-85
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• 2003

Water extract from Astragali Radix (AR) was tested for the safety using Ames, Bacillus subtilis Rec, and umu gene expression mutagenicity tests. Mutagenic activity in any assays we tested was not found. In Ames test, Salmonella typhimurium TA98 and TA 100 were used to identify mutagenic property, and the number of histidine revertants was measured. In the Recassay, Bacillus subtilis ${H-17(Rec^+)\;and\;M-45(Rec^-)}$ strains were used to test DNA damage activity. In the SOS umu test, Salmonella typhimurium TA1535 containing plasmid pSK1002 was used as a test strain, and we monitored the levels of umu operon expression by measuring the ${\beta}-galactosidase$ activity. From the results, there was no DNA damage and mutagenicity of AR. Hepatotoxicity of AR to female ICR mice was also monitored by the measurements of s-GOT, s-GPT, LDH activities after oral feeding for 15 days. AR was not shown any significant changes of s-GOT, s-GPT and LDH activities in mice sera.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.529.2-529
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• 1986

pSp-Si (1.6kbp) was originally found in pediococcus halophilus to be a cryptic multicopy-plasmid. Hoping that the plasmid can also replicate in Bacillus subtilis, protoplast transformation of strain 207-25 (recE) was performed using pSP-Sl onto which was added the marker of tmrB8 (on 4.9 kbp EcoRI fragment ) or tmrB+ (on 0.9 kbp xbaI fragment) gene. Though the tmrB8 gene can expres tunicamycin-resistance at the single copy state, and the tmrB+ gene exerts the resistance only at the multicopy state, we could not confirm the replication of pSP-Sl (tmrB8) or pSP-Sl(tmrB+) in B. subtilis. During the experiment, however, we unexpectedly found that the circularized 0.9 kbp xgaI fragment (tmrB+) itself, which had no replication origin, could transform strain 207-25 to tunicamycin-resistant by protoplast transformation. Southern hybridization analyses with tmrB+ and other probes revealed the integration of the fragment at a single copy state into a position other than the homologous tmrB gene. This recE independent integration of another tmrB+ gene into the chromosome may contribute to the tunicamycinresistance in the transformants.

• 식물병연구
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• 제24권4호
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• pp.339-341
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• 2018

Amaranth has the potential for good materials related to nutrients and health benefits. There are several diseases of amaranth such as leaf blight, damping-off, and root rot. As a causal agent of soft rot disease, Pectobacterium spp. could infect various plant species. In this study, we isolated the bacterial pathogen causing soft rot of amaranth in South Korea. In Gangneung, Gangwon province during 2017, amaranth plants showed typical soft rot symptoms such as wilting, defoliation and odd smell. To isolate pathogen, the macerated tissues of contaminated amaranth were spread onto LB agar plates and purified by a single colony subculture. One ml bacterial suspension of a representative isolate was injected to the stem of five seedlings of 2-week-old amaranth with a needle. Ten mM magnesium sulfate solution was used as a negative control. 16S rDNA gene and recA gene were sequenced and compared with the reference sequences using the BLAST. In the phylogenetic tree based on 16S rDNA gene and recA gene, GSA1 strain was grouped in Pcb.

• The Plant Pathology Journal
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• 제26권3호
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• pp.223-230
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• 2010

The Burkholderia cepacia complex isolates causing bacterial fruit rot of apricot were characterized by speciesspecific PCR tests, recA-HaeIII restriction fragment length polymorphism (RFLP) assays, rep-PCR genomic fingerprinting, recA gene sequencing, and multilocus sequence typing (MLST) analysis. Results indicated that the isolates Bca 0901 and Bca 0902 gave positive amplifications with primers specific for B. vietnamiensis while the two bacterial isolates showed different recA-RFLP and rep-PCR profiles from those of B. vietnamiensis strains. In addition, the two bacterial isolates had a higher proteolytic activity compared with that of the non-pathogenic B. vietnamiensis strains while no cblA and esmR marker genes were detected for the two bacterial isolates and B. vietnamiensis strains. The two bacterial isolates were identified as Burkholderia seminalis based on recA gene sequence analysis and MLST analysis. Overall, this is the first characterization of B. seminalis that cause bacterial fruit rot of apricot.

• 미생물학회지
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• 제29권6호
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• pp.392-396
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• 1991

Pseudomonas sp. DJ77의 chromosomal DNA로부터 6.9kb XhoI 절편 상에 존재하는 phenanthrene 분해에 관련된 유전자군을 vector pBLUESCRIPT SK(+)에 클로닝하였다. 이렇게 얻은 재조합 plasmid인 pHENX7을 가지고 있는 JM101 균주는 3-methylcarechol을 노란색의 meta-cleavage 화합물로 전환할 수 있었다. 그러나 삽입된 절편의 방향이 반대가 되도록 제조한 pHENX7은 extradiol dioxygenase 활성을 나타내지 않기 때문에 전사방향을 알 수 있었다. pHENX7과 이의 듀도체들을 지니는 JH101균주에서 PhnC(24kDa), PhnD(31KDa), PhnE(34kDa), PhnF(KDa)의 4 polypeptide를 확인 할 수 있었고 개개의 유전자의 위치와 범위를 알 수 있었다. 유전자 순서는 phnC-phnD-phnE-phnF-phnG이었으며, phnC, phnD, phnE, phnF, phnG는 각기 glutathione S-transferase, meta-cleavage compound hydrolase extradiol dioxygenase, meta-cleavage compound dehydrogenase의 유전자이었다.