• Bulletin of the Korean Chemical Society
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• 제34권3호
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• pp.743-748
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• 2013

The temperature dependence of the partition coefficients of a neuropeptide, substance P (SP), in isotropic acidic bicelles was investigated by using a pulsed field gradient nuclear magnetic resonance diffusion technique. The addition of negatively charged dimyristoylphosphatidylserine to the neutral bicelle changed the SP partitioning a little, which implies that the hydrophobic interaction between the hydrophobic residues of SP and the acyl chains of lipid molecules is the major interaction while the electrostatic interaction is minor in SP binding in a lipid membrane. From the temperature dependence of the partition coefficients, thermodynamic functions were calculated. The partitioning of SP into the acidic bicelles is enthalpy-driven, as it is for small unilamellar vesicles and dodecylphosphocholine micelles, while peptide partitioning into a large unilamellar vesicle is entropy-driven. This may mean that the size of lipid membranes is a more important factor for peptide binding than the surface curvature and surface charge density.

• 한국패류학회지
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• 제27권2호
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• pp.121-129
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• 2011

The ultrastructural characteristics of germ cell development during spermatogenesis and mature sperm morphology of in male Scapharca subcrenata were investigated by transmission electron microscope observation. Spermatogonia are located nearest the outer wall of the acinus, while spermatocytes and spermatids are positioned near the accessory cells. The accessory cells, which is in close contact with developing germ cells, contained a large quantity of glycogen particles and lipid droplets in the cytoplasm. Therefore, it is assumed that they are involved in supplying of the nutrients for germ cell development. The morphologies of the sperm nucleus and the acrosome of this species are the oval shape and cone shape, respectively. Spermatozoa are approximately 45-$50{\mu}m$ in length including a sperm nucleus (about $1.30{\mu}m$ in length), an acrosome (about $0.59{\mu}m$ in length), and tail flagellum (about 43-$47{\mu}m$). The axoneme of the sperm tail shows a 9 + 2 structure. As some characteristics of the acrosomal vesicle structures, the right and left basal rings show electron opaque part (region), and also the anterior apex part of the acrosomal vesicle shows electron opaque part (region). These characteristics of the acrosomal vesicle were found in Acinidae and other several families in subclass Pteriomorphia. These common characteristics of the acrosomal vesicle in subclass Pteriomorphia can be used for phylogenetic and taxonomic analysis as a taxonomic key or a significant tool. The number of mitochondria in the midpiece of the sperm of this species are five, as one of common characteristics appear in most species in Arcidae and other families in subclass Pteriomorphia. The acrosomal vesicles of Arcidae species do not contain the axial rod and several transverse bands in acrosome, unlkely as seen in Ostreidae species in subclass Pteriomorphia, These characteristics can be used for the taxonomic analysis of the family or superfamily levels as a systematic key or tools.

• Molecules and Cells
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• 제26권6호
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• pp.517-529
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• 2008

Porosomes are supramolecular, lipoprotein structures at the cell plasma membrane, where membrane-bound secretory vesicles transiently dock and fuse to release inravesicular contents to the outside during cell secretion. The mouth of the porosome opening to the outside, range in size from 150 nm in diameter in acinar cells of the exocrine pancreas, to 12 nm in neurons, which dilates during cell secretion, returning to its resting size following completion of the process. In the past decade, the composition of the porosome, its structure and dynamics at nm resolution and in real time, and its functional reconstitution into artificial lipid membrane, have all been elucidated. In this mini review, the discovery of the porosome, its structure, function, isolation, chemistry, and reconstitution into lipid membrane, the molecular mechanism of secretory vesicle swelling and fusion at the base of porosomes, and how this new information provides a paradigm shift in our understanding of cell secretion, is discussed.

• BMB Reports
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• 제37권4호
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• pp.460-465
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• 2004

A 16-residue polypeptide model with the sequence acetyl-YALSLAATLLKEAASL-OH was derived by rational de novo peptide design. The designed sequence consists of amino acid residues with high propensity to adopt an alpha helical conformation, and sequential order was arranged to produce an amphipathic surface. The designed sequence was chemically synthesized using a solid-phase method and the polypeptide was purified by reverse-phase liquid chromatography. Molecular mass analysis by electro-spray ionization mass spectroscopy confirmed the correct designed sequence. Structural characterization by circular dichroism spectroscopy demonstrated that the peptide adopts the expected alpha helical conformation in 50% acetonitrile solution. Liposome binding assay using Small Unilamellar Vesicle (SUV) showed a marked release of entrapped glucose by interaction between the lipid membrane and the tested peptide. The channel-forming activity of the peptide was revealed by a planar lipid bilayer experiment. An analysis of the conducting current at various applied potentials suggested that the peptide forms a cationic ion channel with an intrinsic conductance of 188 pS. These results demonstrate that a simple rational de novo design can be successfully employed to create short peptides with desired structures and functions.

• Reproductive and Developmental Biology
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• 제32권3호
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• pp.147-152
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• 2008

The aim of this study was to investigate what components of porcine epididymal fluid (pEF) influences the nuclear maturation of porcine germinal vesicle oocytes. Porcine cumulus-oocytes complexes from follicles were cultured in TCM 199 containing pEF. After 48 h cultures, oocytes were examined for evidence of GV breakdown, metaphase I, anaphase-telophase I, and metaphase II. Maturation rate of oocytes was significantly increased in media supplemented with 10% pEF during in vitro maturation (IVM) than in those without pEF. When lipid component of pEF was removed by treating n-heptane, no significant difference was observed in maturation of oocytes between n-heptane treatrment and intact pEF group. However, the proportion of oocytes reaching at metaphase II (M II) was significantly (p<0.05) decreased in the oocytes cultured in media containing trypsin-treated pEF compared to those in media with intact pEF. When porcine GV oocytes were matured in the medium supplemented with intact pEF or pEF heated at $56^{\circ}C$ and $97^{\circ}C$, rates of oocytes remained at GV stage were 11.7%, 29.4% and 42.0%, respectively. However, there were no difference in proportion of oocytes reaching at MII stage among intact pEF group and $56^{\circ}C$ group. Present study suggests that 1) pEF contains an enhancing component(s) for nuclear maturation in vitro of oocytes, 2) protein(s) of pEF may be capable to promote nuclear maturation in vitro, and 3) enhancing component for nuclear maturation may consist of two factors, which are responsible for germinal vesicle breakdown (GVBD) and promotion of MII stage.

• 공업화학
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• 제32권5호
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• pp.541-546
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• 2021

세라마이드와 인지질, 콜레스테롤 등과의 상호적 자가회합이 가능한 최적의 조성을 구성하여 세라마이드 고함량의 수화 액정형 베시클을 제조하였다. 혼합조성을 달리하여 다양한 베시클을 제조한 결과, 에지 액티베이터인 sodium deoxycholate (SDOC)와 가용화제인 PEG-60 hydrogenated castor oil (HCO 60)을 혼합하여 베시클을 만들었을 때, 가장 작은 나노 사이즈의 입자가 만들어지고, 베시클 분산액은 약산성이면서 가장 안정한 상태를 유지하였다. 또한 편광현미경과 열분석을 통해 SDOC와 HCO 60의 첨가가 세라마이드 등 지질 성분의 결정성 억제에 영향을 미치는 것으로 확인되었다. 베시클 분산액은 8주 동안의 고온의 장기 보관에서도 외관 및 점도의 변화없이 안정성이 그대로 유지되었다.

• 한국응용과학기술학회지
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• 제19권1호
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• pp.10-18
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• 2002

In this study, it should be mentioned that Lipid-LCG can be prepared with the main compound of hydrogenated lecithin in oil-in water emulsion. The results of its physical property and stability are as follows. First, the best suitable compositions of Lipid-LCG are made from 4.0wt% of the hydrogenated lecithin, 4.0wt% of cetostearyl alcohol as emulsifier and gelling agent, 3.0wt% of butylene glycol and 2.0wt% glycerin as moisturizers, 3.0wt% of cyclomethicone, 3.0wt% of isononyl-isononanoate, 3.0wt% of capric/caprylic triglycerides, 3.0wt% of macadamia oil as emollients. Second, As the optimum conditions to form Lipid-LCG, which figured out 6.0 ${\pm}$ 1.0 for pH level, 32kg/mm, min for hardness to make a .essence to be formed the ternary phase of liquid crystal(multi-lamellar type). Third, as the analytical result of this system, it obtained that particle size is $1{\sim}8{\mu}m$ level, and is certified with it at 400 and 1,000 magnifications by microscope. The stability of Lipid-LCG is very stable on condition of a low temperature ($4^{\circ}C$), a room temperature ($25^{\circ}C$) and a high temperature ($40^{\circ}C$), which is not to be split in for a long time(for 3-month). We produced our own moisturizing essence, which has a good affinity to skin by means of this system.

• IMMUNE NETWORK
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• 제22권2호
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• pp.19.1-19.20
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• 2022

Coxsackievirus B3 (CVB3) infection causes acute pancreatitis and myocarditis. However, its pathophysiological mechanism is unclear. Here, we investigated how lipid metabolism is associated with exacerbation of CVB3 pathology using high-fat diet (HFD)-induced obese mice. Mice were intraperitoneally inoculated with 1×10⁶ pfu/mouse of CVB3 after being fed a control or HFD to induce obesity. Mice were treated with mitoquinone (MitoQ) to reduce the level of mitochondrial ROS (mtROS). In obese mice, lipotoxicity of white adipose tissue-induced inflammation caused increased replication of CVB3 and mortality. The coxsackievirus adenovirus receptor increased under obese conditions, facilitating CVB3 replication in vitro. However, lipid-treated cells with receptor-specific inhibitors did not reduce CVB3 replication. In addition, lipid treatment increased mitochondria-derived vesicle formation and the number of multivesicular bodies. Alternatively, we found that inhibition of lipid-induced mtROS decreased viral replication. Notably, HFD-fed mice were more susceptible to CVB3-induced mortality in association with increased levels of CVB3 replication in adipose tissue, which was ameliorated by administration of the mtROS inhibitor, MitoQ. These results suggest that mtROS inhibitors can be used as potential treatments for CVB3 infection.

• Korean Chemical Engineering Research
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• 제53권6호
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• pp.672-676
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• 2015

구형인지질이중층인 소낭이 이중에멀젼기법에 의해서 제조되었다. 소낭의 바깥층에서 인지질분해효소D에 의해 촉진되는 Phosphatidylcholine의 Phosphatidic-acid 전환은 소낭의 곡률반경을 변화시키고 궁극적으로는 소낭들의 융합을 유도한다. 인지질층의 물성이 융합에 끼치는 영향을 형광세기변화의 측정으로 규명하였다. 측정 전에, 형광세기에 대한 융합의 등급화를 수행하였다. 8-Aminonaphthalene-1,3,6-trisulfonic acid disodium salt(ANTS)와 p-Xylene-bis(N-pyridinium bromide)(DPX)이 각각 캡슐화된 소낭들을 1:1로 섞은 조건의 형광세기를 0% 융합으로 설정하였으며, ANTS와 DPX가 섞인 채로 캡슐화된 소낭의 형광세기를 100% 융합으로 설정하였다. 형광물질의 누출을 고려하여 별도의 실험에서 누출에 의한 형광세기 변화를 측정하였다. 인지질분해효소D에 의해 유도된 소낭들의 거동을 관찰한 결과, 안층이 액상인 조건에서만 융합이 일어났다. 그러나, 융합은 바깥층의 상에 의해서는 영향을 받지 않는 것으로 나타났다. 바깥층의 상은 누출에 영향을 주었으며, 이 결과는 층의 밀도와 측면확산에 기인한 것으로 이해된다.

• Journal of Pharmaceutical Investigation
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• 제22권2호
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• pp.115-124
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• 1992

The characteristics and stabilities of phosphatidylcholine liposomes covalently coupled with immunoglobulin fragments prepared by the REV method were investigated by the dynamic light scattering, absorbance and calcein release. Using a sulfhydryl-reactive phospholipid derivative of N-[4$({\rho}-maleimido-phenyl)$ butyl] phosphatidylethanolamine (MPB-PE), Fab' antibody fragments were covalently combined with preformed large unilamellar vesicles (LUV), Coupling ratio was $250\;{\mu}g$ of $Fab'/{\mu}mol$ of phospholipid in vesicles, From dynamic light scattering, it was found that the size of the vesicles increases as the ratio of cholesterol to lipid increases, but that apparently, the size of liposomes was not sensitive to the existence of Fab' fragments. Regardless of inserting Fab' fragments, the absorbance of liposomes decreased as the amounts of bile salt (BS) added. At very low BS concentrations, BS/lipid aggregates would be formed in the outer vesicles monolayer, while, at the high BS concentrations, mixed micelles would be preferred. The vesicles incorporated with Fab' fragments, however, are more resistant to the bile salts than the MPB-PE vesicle are. The absorbance of vacant liposomes and calcein release resulted in that the Fab' vesicles and MPB-PE vesicles by the REV method are very stable, but that those by the sonication method sufferred the significant change of turbidities.