• Journal of Microbiology and Biotechnology
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• 제28권5호
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• pp.826-830
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• 2018

A Cre/loxP-${\delta}$-integration system was developed to allow sequential and simultaneous integration of a multiple gene expression cassette in Saccharomyces cerevisiae. To allow repeated integrations, the reusable Candida glabrata MARKER (CgMARKER) carrying loxP sequences was used, and the integrated CgMARKER was efficiently removed by inducing Cre recombinase. The XYLP and XYLB genes encoding endoxylanase and ${\beta}$-xylosidase, respectively, were used as model genes for xylan metabolism in this system, and the copy number of these genes was increased to 15.8 and 16.9 copies/cell, respectively, by repeated integration. This integration system is a promising approach for the easy construction of yeast strains with enhanced metabolic pathways through multicopy gene expression.

• Journal of Korean Biological Nursing Science
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• 제8권1호
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• pp.5-14
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• 2006

Staphyloccus aureus is one of the most important pathogens in clinical settings. It is also one of the leading causes of nosocomial infections and the dissemination of multiple drug-resistant strains, mainly methicillin resistant Staphyloccus aureus, and the recent emergence of a vancomycin resistant MRSA is the concern to hospital worldwide. MRSA strains have acquired multiple resistance to a wide range of antibiotics, including aminoglycosides and macrolides. $\beta$-Lactam resistance of methicillin-resistnat Staphyococcus aureus is determined by the function of penicillin binding protein 2'(PBP2') encoded by the methicillin resistance gene mec A. MRSA strains carry methicillin resistance gene mecA, encoded by a mobile genetic element designated staphylococoal cassette chromosome mec(SCCmec). MRSA clones are defined by the type of SCCmec element and the genotype of the methicilline-susceptible Staphyococcus aureus chromosome in which the SCCmec element is integrated.

• Journal of Animal Science and Technology
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• 제64권5호
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• pp.1008-1011
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• 2022

We here report the whole genome sequence of Ligilactobacillus agilis C7 with anti-listerial activity, which was isolated from pig feces. The genome size of L. agilis C7 (~ 3.0 Mb) is relatively larger compared with other L. agilis strains. L. agilis C7 carries three bacteriocin gene clusters encoding garvicin Q, salivaricin A, and Blp family class II bacteriocin. Garvicin Q and salivaricin A are reported to be active against Listeria monocytogenes and Micrococcus luteus, respectively, as well as against other Gram-positive bacteria. Meanwhile, the bacteriocin encoded in the blp cassette was shown to be active against pneumococci, mediating intraspecies competition. This report highlights the potential of L. agilis C7 for the production of bacteriocins inhibiting pathogenic bacteria.

• 한국자원식물학회지
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• 제17권2호
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• pp.161-168
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• 2004

Ferritin light heavy chain (FLHC) gene는 일부 중금속과 결합, 저장 및 운반하여 무독화 시킬 수 있는 것으로 알려져 있다. Fe 관련 유전자인 FLHC유전자를 식물 발현용 promoter인 35S promoter와 Tnos를 사용하여 식물 형질전환용 vector를 재조합하였다. 식물세포형질전환용 binary vector는 상기 cassette vector가 조립이 매우 양호하며 border sequence를 가지고 있는 pRD400 binary vector를 사용하여 최종적으로 가나마이신 내성 유전자 (NPT II gene)와 tadpole ferritin heavy chain gene 및 human ferritin light chain gene를 함유하고 있는 binary vector를 재조합하였다. Binary vector의 아그로박테리움에 도입은 triparental mating 방법에 의하여 수행하여 AB배지 및 가나마이신 함유 배지에서 disarmed Ti-vector를 가지고 있는 Agrobacterium tumefaciens MP90/FLHC을 선발하였다. FLHC 유전자 도입된 식물형질전환용 binary vector를 이용하여 형질전환방법을 변형하여 많은 embryo를 유도하였으며 유도된 embryo들은 GA 10mg/L가 첨가된 배지에 지상부를 유도하였다. 형질전환체식물체의 정상적인 생장을 유도하기 위해 최적의 배양조건을 조사하였던 바, 비교적 1/3 MS배지에서 뿌리의 생장과 지상부의 생장이 균일하게 생장하는 경향을 보였으며, 뿌리와 줄기가 잘 발달된 약 7cm의 유식물체를 대량으로 증식하여, 모래와 흙이 1:1로 혼합된 토양에 옮겼다.

• 한국식품위생안전성학회지
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• 제29권3호
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• pp.223-227
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• 2014

원유시료에서 분리한 methicillin 내성 황색포도알균의 분표율과 내성유전자의 분석을 분자수준에서의 실시하였다. 총 698종의 원유시료에서 286개의 포도알균속 세균을 Staphylococcus Medium 110을 이용하여 분리 후 Vitek 2 system을 이용하여 동정한 결과 94개의 황색포도알균을 확인하였다. 94개의 황색포도알균 중 총 7개의 균에서 methicillin 내성 mecA 유전자가 존재함을 확인하였다. Methicillin-resistant Staphylococcus aureus (MRSA)로 확인된 7 균주에 대해 수종의 항생제에 대한 감수성 시험, staphylococcal cassette chromosome mec (SCCmec) typing, 및 병독소유전자인 Panton-Valentine Leukocidin (pvl)유전자를 분석하였다. 그 결과 7종의 mecA 양성 MRSA 모두 ampicillin과 oxacillin에 내성이었으며 teicoplanin, vancomycin 및 ciprofloxacin에는 모두 감수성임을 확인하였다. 한편 SCCmec typing결과 7균 중 1균주는 SCCmec type II로 확인되었고 6균주는 SCCmec type IV로 확인되었으며 병독소 유전자인 pvl유전자는 검출되지 않았다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.99-102
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• 2001

본 연구에서는 히루딘을 생산할 수 있는 재조합 S. cerevisiae 에서 ‘히루딘 유전자의 copy number 와 히루딘 발현양과의 관계를 규명하였으며 , ${\delta}$ 서열을 이중으로 사용한 히루딘 발현벡터를 제조하여 히루딘 유전자의 효모염색체로의 도입효율을 증가시켰다. 숙주세포인 효모의 GALl 유전자를 파쇄하여 균체에 의한 갈락토스 소모를 방지하여 보다 경제적으로 히루딘을 생산할 수 있는 시스템을 개발하였으며, 재조합 H. polymorpha을 이용한 발효공정에서 히루딘 생산을 위한 최적의 메탄올 농도를 결정하였다.

• BMB Reports
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• 제36권3호
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• pp.275-281
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• 2003

An E1B-defective adenovirus, named r2/Ad carrying the neo expression cassette, was constructed by homologous recombination. The construction, selection (using neomycin as a selective marker), and propagation of the recombinant virus was performed in human embryonic kidney 293 cells (HEK 293). An in vitro study demonstrated that this recombinant virus has the ability to replicate in and lyse some p53-deficient human tumor cells such as human glioma tumor cells (U251) and human bladder cells (EJ), but not in some cells with functional p53, such as human adenocarcinoma cells (A549) and human fibroblast cells (MRC-5). Also, based on the cytopathic effect (CPE), it was demonstrated, under identical conditions, that the U251 cells were more sensitive to r2/Ad replication than the EJ cells. In this paper, we report that r2/Ad could be very useful in studying the in vitro selective replication of E1B-defective adenovirus and has great potential in cancer gene therapy.

• Journal of Microbiology and Biotechnology
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• 제20권4호
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• pp.678-682
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• 2010

The deletion of sti from the Streptomyces plasmid pIJ101 made its derivative pHZ1358 an efficient vector for gene disruption and replacement. Here, pHZ1358 was further optimized by the construction of a derivative plasmid pJTU1278, in which a cassette carrying multiple cloning sites and a lacZ selection marker were introduced for convenient plasmid construction in E. coli. In addition, the oriT region of pJTU1278 was also deleted, generating a vector (pJTU1289) that can be used specifically for PCR-targeting. The efficient usage of these vectors was demonstrated by the deletion of the gene involved in avermectin biosynthesis in S. avermitilis.

• 대한임상검사과학회지
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• 제43권2호
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• pp.68-74
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• 2011

Pseudomonas aeruginosa is an aerobic, Gram-negative, glucose-nonfermenting bacterium, which has emerged as a serious opportunistic pathogen. Recently, outbreaks of carbapenem resistant P. aeruginosa give rise to significant therapeutic challenges for treating nosocomial infections. The genes of metallo-${\beta}$-lactamase (MBL), a powerful carbapenemase, are carried as a part of the mobile gene cassettes inserted into integrons playing an important role in rapid dissemination of antibiotic resistance genes among bacterial isolates. In this study, we investigated the prevalence of integron in imipenem resistant P. aeruginosa isolates. A total of 61 consecutive, non-duplicate, and imipenem resistant P. aeruginosa strains were isolated from a university hospital in the Chungcheong province of Korea. We employed repetitive extragenic palindromic sequence-based PCR (rep-PCR) method for the selection of clonally different P. aerusinosa strains. PCR and DNA sequencing were conducted for the detection of integrons. Twenty-one clonally different P. aeruginosa strains were isolated. Only one (P28) of the strains harbored $bla_{VIM-2}$ that was found as gene cassettes in class 1 integrons. Four of 21 carbapenem resistant P. aeruginosa strains harbored class 1 integron containing aminoglycoside resistance determinant. All of the integrons detected in the study contained more than one resistance gene cassette, which can mediate resistance to multiple antibiotics. To prevent further spreading of the multi-drug resistant P. aeruginosa, conseguent monitoring and clinical polices are required.

• 한국자원식물학회지
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• 제22권3호
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• pp.273-280
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• 2009

A cDNA clone encoding a MDR-like ABC transporter protein was isolated from Brassica rapa seedlings, through rapid amplification of cDNA ends (RACE). This gene (named as Brmdr 1; GenBank accession no.: DQ296184 ) had a total length of 4222 bp with an open reading frame of 3900 bp, and encoded a predicted polypeptide of 1300 amino acids with a molecular weight of 143.1 kDa. The BrMDR1 protein shared 71.0, 62.5, 60.0 and 58.2% identity with other MDR proteins isolated from Arabidopsis thaliana (AAN28720), Coptis japonica (CjMDR), Gossypium hirsutum (GhMDR) and Triticum aestivum (TaMDR) at amino acid level, respectively. Southern blot analysis showed that Brmdr1 was a low-copy gene. Expression pattern analysis revealed that Brmdr1 constitutively expressed in the root, stem petals and stamens, but with lower expression in leaves and open flowers. The domains analysis showed that BrMDR1 protein possessed two transmembrane domains (TMDs) and two nucleotide binding domains (NBDs) arranging in "TMD1-NBD1-TMD2-NBD2" direction, which is consistent with other MDR transporters. Within NBDs three characteristic motifs common to all ABC transporters, "Walker A", "Walker B" and C motif, were found. These results indicate that BrMDR1 is a MDR-like ABC transporter protein that may be involved in the transport and accumulation of secondary metabolites.