• 한국미생물·생명공학회지
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• 제40권3호
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• pp.274-277
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• 2012

본 연구에서는 다제내성을 보이는 인체 병원균의 하나인 S. aureus에서 유래된 FtsZ 단백질의 유전자를 클로닝하고 대장균에 형질전환하여 재조합 단백질을 만들고, in vitro 상에서 폴리머 형성 활성을 측정하였다. Bradford 방법을 이용하여 SA FtsZ단백질의 농도를 측정한 후, SA FtsZ단백질의 폴리머 형성 활성을 확인하기 위해 형광계를 이용하여 excitation 방향과 $90^{\circ}$의 방향에서 산란되는 빛의 양을 측정하는 방법을 사용하였을 때에 대조군에서는 빛이 산란되지 않았고, SA FtsZ 단백질에 GTP와 $Mg^{2+}$를 처리한 실험군에서만 빛이 산란되는 현상을 관찰하였다. 1분여의 시간이 지난 이후에는 다시 산란되는 빛이 줄어드는 것을 볼 수 있는데, 이것은 SA FtsZ 단백질의 아미노말단 도메인의 GTPase 활성에 의해서 GTP가 분해되어서 SA FtsZ 단백질의 폴리머가 단량체로 분해되었기 때문이라고 예측된다. 본 연구를 통하여 확립된 SA FtsZ 활성 측정 방법은 향후 SA FtsZ 단백질의 폴리머 형성을 저해하는 방식으로 S. aureus를 표적으로 하는 항생제 후보물질 도출을 위한 스크리닝 방법으로 사용될 수 있을 것이다.

• Molecules and Cells
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• 제39권11호
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• pp.814-820
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• 2016

FtsZ, a tubulin homologue, is an essential protein of the Z-ring assembly in bacterial cell division. It consists of two domains, the N-terminal and C-terminal core domains, and has a conserved C-terminal tail region. Lateral interactions between FtsZ protofilaments and several Z-ring associated proteins (Zaps) are necessary for modulating Z-ring formation. ZapD, one of the positive regulators of Z-ring assembly, directly binds to the C-terminal tail of FtsZ and promotes stable Z-ring formation during cytokinesis. To gain structural and functional insights into how ZapD interacts with the C-terminal tail of FtsZ, we solved two crystal structures of ZapD proteins from Salmonella typhimurium (StZapD) and Escherichia coli (EcZapD) at a 2.6 and $3.1{\AA}$ resolution, respectively. Several conserved residues are clustered on the concave sides of the StZapD and EcZapD dimers, the suggested FtsZ binding site. Modeled structures of EcZapD-EcFtsZ and subsequent binding studies using bio-layer interferometry also identified the EcFtsZ binding site on EcZapD. The structural insights and the results of bio-layer interferometry assays suggest that the two FtsZ binding sites of ZapD dimer might be responsible for the binding of ZapD dimer to two protofilaments to hold them together.

• Journal of Microbiology and Biotechnology
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• 제27권11호
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• pp.1994-1998
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• 2017

FtsZ, a bacterial cell-division protein, is an attractive antibacterial target. In the screening for an inhibitor of Staphylococcus aureus FtsZ, madurahydroxylactone (1) and its related derivatives 2-5 were isolated from Nonomuraea sp. AN100570. Compound 1 inhibited S. aureus FtsZ with an $IC_{50}$ of $53.4{\mu}M$ and showed potent antibacterial activity against S. aureus and MRSA with an MIC of $1{\mu}g/ml$, whereas 2-5 were weak or inactive. Importantly, 1 induced cell elongation in the cell division phenotype assay, whereas 2-5 did not. It indicates that 1 exhibits its potent antibacterial activity via inhibition of FtsZ, and the hydroxyl group and hydroxylactone ring of 1 are critical for the activity. Thus, madurahydroxylactone is a new type of inhibitor of FtsZ.

• Natural Product Sciences
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• 제21권4호
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• pp.282-288
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• 2015

Viriditoxin is a fungal metabolite isolated from Paecilomyces variotii, which was derived from the giant jellyfish Nemopilema nomurai. Viriditoxin was reported to inhibit polymerization of FtsZ, which is a key protein for bacterial cell division and a structural homologue of eukaryotic tubulin. Both tubulin and FtsZ contain a GTP-binding domain, have GTPase activity, assemble into protofilaments, two-dimensional sheets, and protofilament rings, and share substantial structural identities. Accordingly, we hypothesized that viriditoxin may inhibit eukaryotic cell division by inhibiting tubulin polymerization as in the case of bacterial FtsZ inhibition. Docking simulation of viriditoxin to ${\beta}-tubulin$ indicated that it binds to the paclitaxel-binding domain and makes hydrogen bonds with Thr276 and Gly370 in the same manner as paclitaxel. Viriditoxin suppressed growth of A549 human lung cancer cells, and inhibited cell division with G2/M cell cycle arrest, leading to apoptotic cell death.

• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.307-316
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• 2015

Beginning from the recognition of FtsZ as a bacterial tubulin homolog in the early 1990s, many bacterial cytoskeletal elements have been identified, including homologs to the major eukaryotic cytoskeletal elements (tubulin, actin, and intermediate filament) and the elements unique in prokaryotes (ParA/MinD family and bactofilins). The discovery and functional characterization of the bacterial cytoskeleton have revolutionized our understanding of bacterial cells, revealing their elaborate and dynamic subcellular organization. As in eukaryotic systems, the bacterial cytoskeleton participates in cell division, cell morphogenesis, DNA segregation, and other important cellular processes. However, in accordance with the vast difference between bacterial and eukaryotic cells, many bacterial cytoskeletal proteins play distinct roles from their eukaryotic counterparts; for example, control of cell wall synthesis for cell division and morphogenesis. This review is aimed at providing an overview of the bacterial cytoskeleton, and discussing the roles and assembly dynamics of bacterial cytoskeletal proteins in more detail in relation to their most widely conserved functions, DNA segregation and coordination of cell wall synthesis.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.722-725
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• 1999

Filamentation-suppressed recombinant Escherichia coli strain harboring the Alcaligenes latus polyhydroxyalkanoate (PHA) biosynthesis genes and the E. coli ftsZ gene was constructed and cultivated for the production of poly(3-hydroxybutyrate) [P(3HB)] with high concentration and high content. By the pH-stat fed-batch culture of this recombinant E. coli strain XL1-Blue(pJC5), the final cell concentration and P(3HB) concentration obtained in 44.25h were 172.2g cell dry weight/l and 141.9g P(3HB)/l, respectively, resulting in productivity of 3.21g P(3HB)/l-h. More importantly, the P(3HB) content obtained was 82.4 wt %, which was significantly higher than that obtained with the recombinant E. coli harboring only the PHA biosynthesis genes.

• Journal of Plant Biotechnology
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• 제34권3호
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• pp.271-275
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• 2007

엽록체 형질전환된 식물체를 얻으려면 먼저 세포수준에서 모든 엽록체가 형질전환되어야 하는데, 세포내에는 많은 수의 엽록체가 존재하므로, 엽록체 형질전환 벡터가 전이되어 형질전환된 엽록체는 선발배지에서 선택적으로 분열을 계속하고 형질전환되지 않은 엽록체들은 분열을 하지 못하게 되어, 결국 해당 세포내의 모든 엽록체가 형질전환된 상태에 이르게 된다. 따라서 만일 해당 세포내에 엽록체의 수가 적으면 그만큼 효율적으로 엽록체 형질전환을 할 수 있을 것이다. 본 연구에서는 담배의 FtsZ 유전자를 핵형질전환법으로 과잉 발현시킴으로써 엽록체의 분열이 저해되어 엽육세포내에 거대한 엽록체 3-5개를 가진 담배식물체의 엽육조직을 이용하여, 엽록체 형질전환을 한 결과, 엽록체 형질전환 빈도가 약 40% 증가되었다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.613-616
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• 2008

We report on electrical and optical properties of flexible ITO electrode grown on PET substrate using a specially designed roll-to-roll facing target sputtering (R2R FTS) system at room temperature without conventional cooling drum. Due to effective confinement of high density plasma between ITO targets, we can grow a flexible ITO electrode without cooling drum at room temperature.

• 한국전기전자재료학회논문지
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• 제29권5호
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• pp.279-283
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• 2016

In this study, we intended to achieve both antibacterial properties and electromagnetic shielding using the Al-doped ZnO (AZO) films. FTS (Facial Target Sputtering) magnetron sputtering was used for the AZO thin films instead of the conventional RF sputtering because the FTS sputtering could avoid the damage for the plasma as well as fabrication of thin films with a high quality. The 300-nm thick AZO thin films grown on glass substrate showed a resistivity of about $7{\times}10^{-4}{\Omega}-cm$ and a transmittance of about 90% at a wavelength of 550 nm. AZO thin films were investigated for the electromagnetic shielding effectiveness measured by 2-port network method at 1.5 ~ 3 GHz. The AZO (300 nm)/glass films showed an EMI shielding effectiveness of approximately 27 dB. An antibacterial effect was measured by the film attachment method (JIS Z 2801). The percent reductions of bacteria by AZO films were 99.99668% and 99.99999% against Staphylococcus aureus and Escherichia coli, respectively.

• 한국응용곤충학회지
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• 제40권4호
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• pp.321-326
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• 2001

Wolbachia 감염이 디코폴 감수성계통 점박이응애와 저항성계통 점박이응애 적합도에 미치는 영향(발육, 수명, 산란수, 산란기간)을 미니장미를 기주로 조사하였다. ftsZ PCR결과 감수성 계통만이 Wolbachia에 감염된 것으로 조사되었다. 감수성계통은 저항성계통에 비해 높은 산란율과 빠른 발육률이 관찰되었으며, 성충수명과 산란기간은 감수성계통에서 길었다. 이는 적합도가 디코폴저항성 수준에 영향을 받고 있음을 보여주고 있다. 동일한 조사를 상호교배 자손에서 조사한 결과, Wolbachia에 감염된 수컷과 Wolbachia 비감염 암컷을 교배한 조합에서 높은 난사망율과 수컷편중 성비가 관찰되어 전형적인 Wolbachia에 의해 유도되는 세포질 불화합성을 보여주고 있다. 또한 Wolbachia에 감염된 암컷과 Wolbachia 비감염 수컷조합의 내적자연증가율값($0.09\pm$0.01)은 다른 조합($0.20\pm$0.01)에 비해 유의하게 낮았다. 본 실험의 연구결과는 점박이응애 적합도의 발달과 진화가 저항성 수준과 Wolbachia 감염에 밀접하게 연관되어 있음을 보여주고 있다.