• Journal of Microbiology and Biotechnology
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• 제19권1호
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• pp.37-41
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• 2009

Previous studies have demonstrated that Shewanella decolorationis S12 can grow on the azo compound amaranth as the sole electron acceptor. Thus, to explore the mechanism of energy generation in this metabolism, membranous vesicles (MVs) were prepared and the mechanism of energy generation was investigated. The membrane, which was fragmentized during preparation, automatically formed vesicles ranging from 37.5-112.5 nm in diameter under electron micrograph observation. Energy was conserved when coupling the azoreduction by the MVs of an azo compound or Fe(III) as the sole electron acceptor with $H_2$, formate, or lactate as the electron donor. The amaranth reduction by the vesicles was found to be inhibited by specific respiratory inhibitors, including $Cu^{2+}$ ions, dicumarol, stigmatellin, and metyrapone, indicating that the azoreduction was indeed a respiration reaction. This finding was further confirmed by the fact that the ATP synthesis was repressed by the ATPase inhibitor N,N'-dicyclohexylcarbodiimide (DCCD). Therefore, this study offers solid evidence of a mechanism of microbial dissimilatory azoreduction on a subcell level.

• Applied Microscopy
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• 제28권1호
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• pp.83-90
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• 1998

본 연구에서는 박절편과 동결할단복제법을 이용하여 흰쥐 간세포에서 dehydrocholic acid가 수송되는 경로를 전자현미경적으로 조사하고자 하였다. 정상군이나 dehydrocholic acid 투여군에서 대부분의 Golgi 장치는 형성면을 담세관으로 향하고 있었다. Dehydrocholic acid 투여 20분 후에 세포질내세망과 Golgi 장치 및 소포 등이 담세관 주위에 증가되어 있었는데 특히 Golgi 장치 형성면에서는 소포가 될 것으로 추정되는 싹이 돌출되어 있었으며 소포들은 담세관에 융합된 것들도 관찰되었다. 이러한 소견으로 미루어 담즙산의 분비는 Golgi 장치 형성면의 쌀이 유리되어 형성된 소포가 담세관막에 융합되므로서 이루어질 것으로 추정된다.

• Translational and Clinical Pharmacology
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• 제26권3호
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• pp.103-110
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• 2018

The human microbiome is known to play an essential role in influencing host health. Extracellular vesicles (EVs) have also been reported to act on a variety of signaling pathways, distally transport cellular components such as proteins, lipids, and nucleic acid, and have immunomodulatory effects. Here we shall review the current understanding of the intersectionality of the human microbiome and EVs in the emerging field of microbiota-derived EVs and their pharmacological potential. Microbes secrete several classes of EVs: outer membrane vesicles (OMVs), membrane vesicles (MVs), and apoptotic bodies. EV biogenesis is unique to each cell and regulated by sophisticated signaling pathways. EVs are primarily composed of lipids, proteins, nucleic acids, and recent evidence suggests they may also carry metabolites. These components interact with host cells and control various cellular processes by transferring their constituents. The pharmacological potential of microbiome-derived EVs as vaccine candidates, biomarkers, and a smart drug delivery system is a promising area of future research. Therefore, it is necessary to elucidate in detail the mechanisms of microbiome-derived EV action in host health in a multi-disciplinary manner.

• Journal of Microbiology and Biotechnology
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• 제32권5호
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• pp.621-629
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• 2022

Bacterial outer membrane vesicles (OMVs) typically contain multiple immunogenic molecules that include antigenic proteins, making them good candidates for vaccine development. In animal models, vaccination with OMVs has been shown to confer protective immune responses against many bacterial diseases. It is possible to genetically introduce heterologous protein antigens to the bacterial host that can then be produced and relocated to reside within the OMVs by means of the host secretion mechanisms. Accordingly, in this study we sought to develop a novel platform for recombinant OMV (rOMV) production in the widely used bacterial expression host species, Escherichia coli. Three different lipoprotein signal peptides including their Lol signals and tether sequences-from Neisseria meningitidis fHbp, Leptospira interrogans LipL32, and Campylobactor jejuni JlpA-were combined upstream to the GFPmut2 model protein, resulting in three recombinant plasmids. Pilot expression studies showed that the fusion between fHbp and GFPmut2 was the only promising construct; therefore, we used this construct for large-scale expression. After inducing recombinant protein expression, the nanovesicles were harvested from cell-free culture media by ultrafiltration and ultracentrifugation. Transmission electron microscopy demonstrated that the obtained rOMVs were closed, circular single-membrane particles, 20-200 nm in size. Western blotting confirmed the presence of GFPmut2 in the isolated vesicles. Collectively, although this is a non-optimized, proof-of-concept study, it demonstrates the feasibility of this platform in directing target proteins into the vesicles for OMV-based vaccine development.

• Toxicological Research
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• 제8권1호
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• pp.95-107
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• 1992

Basolateral and brush border membrance (BLM and BBM) vesicles of renal proximal tubules were prepared from adult male New Zealand White rabbits to develop an experimental for assessment of nephrotoxicity. PAH uptakes using BLMV, and glucose and leucine uptakes using BBMV were measured in the rabbits treated uranyl acetate. In addition, urinalysis and histopathological studies were performed to investigate the correlationship with the membrance vesicle uptakes.

• Journal of Plant Biology
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• 제33권4호
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• pp.321-323
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• 1990

Membrane proteins isolated from the coleoptile and mesocotyl tissues of corn seedlings were solubilized with Triton X100 and reconstituted with phosphatidylcholine at 2$0^{\circ}C$. The proteoliposomes were incubated and proton uptake into the vesicles was measured with a spectrophotometer. Addition of ATP to the reaction mixture was found to result in an active accumulation of proton into the vesicles. These results indicate that the preparation contains tightly bound phosphatidylcholine vesicles with reconstituted H+ -ATPase from the plant cell membranes.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.6-6
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• 1996

Gap junction channels were reconstituted into unilamellar liposomes using immunoaffinity purified connexin 32 gap junction protein from rat liver. Vesicles containing open channels and close channels were separated by means of iso-osmolar sucros density gradient sedimentation. The open channels formed in lipid vesicles were permeable to a fluorescent dye molecule, lucifer yellow of which the hydrodynamic size is similar to pore size of gap junctions in vivo. (omitted)

• 한국발생생물학회지:발생과생식
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• 제1권2호
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• pp.133-139
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• 1997

To study the function and structure of Golgi apparatus in the spermiogenesis of long-fingered bat (Miniopterus schreibersi fuliginosus), the testis obtained from adult bat was treated with the prolonged osmification or fixed with ferrocyanide reduced osmium. golgi apparatus was oval shape in early Golgi phase, and was composed of cortex and medullar enclosing acrosome in mid Golgi phase. The vesicles of crescent shape Golgi apparatus were closed or fused with small or large vesicles at the periphery of acrosome. Golgi apparatus moved behing the acrosome face in cap phase, but the Golgi apparatus was still active. According to this, Golgi apparatus appears to be involved in the formation of acrosome and sperm tail. Transfer of materials from Golgi to acrosme seems to be carried out not only by fusion of large vesicles with acrosomal vesicles but also by detachment of coated vesicle from various cisternae of Golgi fusing with acrosomal vesicle.

• Applied Microscopy
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• 제21권2호
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• pp.117-125
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• 1991

This study has been carried out to investigate the development of dictyosome, and roles of dictyosome about the formation of spherosome in the endosperm cell during seed formation of Panax ginseng with electron microscope. The result is as follows; In the endosperm cells of early stage during seed formation of Panax ginseng, plastid, mitochondria, endoplasmic reticulum, dictyosome and ribosomes are evenly distributed in cytoplasm. Electron lucent vesicles derived from dictyosome are observed in endosperm cells. Vesicles that contain low electron density are derived from forming face of dictyosome and releases into the cytosol. This vesicles formed multi vesicular body or fused with the plasma membrane. The spherical spherosomes are formed from dictyosome containing the lipid materials of even electron density and are gradually increased in size and number. Dictyosome is located in between vacuole and spherosome and it's cisternae form a semicircle and a circle. Some membrane of the protein body that accumulate the storage protein are originate from the spherical vacuole which interfused between vesicles and vacuoles derived from dictyosome.

• 공업화학
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• 제18권1호
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• pp.54-57
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• 2007

Octachlorocyclotetraphosphazene을 사용하여 cyclotetraphosphazene 구조를 내부에 갖고 외부로 8개의 사슬 구조를 갖는 cyclotetraphosphazene 유도체를 합성하였다. 그리고 이 유도체와 콜레스테롤을 사용하여 vesicle을 형성시켰으며, TEM을 이용해서 이 vesicle의 형태를 살펴보고, encapsulation 효율 등을 알아보았다. 이 vesicle의 안정도는 dihexadecylphosphate를 첨가함에 의해서 크게 향상되었다.