• Journal of Periodontal and Implant Science
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• v.30 no.4
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• pp.737-746
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• 2000

본 연구는 hemin이 치주질환 주요 병인균주 중의 하나인 Prevotella intermedia의 성장 및 세포막 단백질의 발현에 미치는 영향을 규명하고, hemin 결합에 관여하는 것으로 추정되는 단백질의 순수분리 및 특성 분석을 위해 수행 되었다. 본 연구의 결과에 의하면, hemin은 P.intermedia의 성장 및 세포막 단백질의 발현에 영향을 미쳐, hemin이 고갈된 조건에서 균주의 성장이 현저히 억제되었으며, 약 50 kDa의 세포막 단백질이 현저히 강화되어 발현되었다. 본 연구에서는 hemin 결합에 관여하는 것으로 추정되는 이 50 kDa의 세포막 단백질을 순수분리하였으며, N'-terminal 아미노산 분석을 수행한 결과 이 단백질은 Streptococcus inter - medius의 Enolase와 아미노산 서열 및 분자량이 일치하였다. 한편, 이 단백질에는 disulfidebond가 존재하지 않았다. 본 연구는 P.intermedia에서의 porphyrin 생리 및 hemin 획득기전을 밝히는데 있어 중요한 의의가 있으리라 사료된다.

• Microbiology and Biotechnology Letters
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• v.30 no.4
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• pp.320-324
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• 2002

To establish a rapidly immunochemical identification on a dinoflagellate, Cochlodinium polykrikoides, a specific antigenic protein as a maker on the cell membrane was isolated. The cell membranes of C. polykrikoides and Gymnodinium sangineum were harvested by centrifugation after osmotic shock. The membrane proteins of both cells were solubilized in 50 mM Na-carbonate contained 1 mM DTT, and separated the proteins on SDS-PACE. Immune-blot on the solubilized membrane proteins of the both cells was performed with antiserum against the solubilized membrane proteins of C. polykrikoides. A 120 kDa membrane protein of C. polykrikoides had remarkablely different antigenicity from that of G. sangineum.

• The Korean Journal of Zoology
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• v.36 no.3
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• pp.342-346
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• 1993

The protein level of cytoskeletons in cultured myoblasts was found to gradually decrease during the course of myogenesis. This decrease, however, could be prevented by treatiag the ceils with calpeptin (benzyloxycarbonyl-Leu-nLeu-H), a cell penetrating inhibitor of calpain. In contrast, E-64, which also is a potent inhibitor of calpain but can not be transported into the cells, showed little or no effect. In addition, the treatment of calpeptin was found to stabilize a number of specific cytoskeletal proteins from degradation but without any effect on the pattern of total cells proteins. Furthermore, calpeptin, but not E-64, blocked myoblast fusion in a dose-dependent manner. These results suggest that calpain is responsible for the myogenic time-dependent loss of cytoskeletal proteins and that the degradative process is associated with myoblast fusion. These results also suggest that the differential effects of the calpain inhibitors depend on the permeabIlity of the drugs across the cell membrane.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.4
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• pp.5-11
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• 2004

생체 시스템은 수많은 세포들로 구성되어 있다. 일반적으로 세포막은 단백질과 지방의 혼합체로 구성되어 있으며 두께는 7.5-10nm 정도이다. 단백질은 지방과 함께 세포막을 통한 물질의 이동을 제어하는 역할을 한다. 특히 지방층은 지방에 잘 용해되는 산소나 탄산가스 등은 잘 통과시키지만, 지방에 잘 용해되지 않는 나트륨, 칼륨, 칼슘, 글루코스, 아미노산 등은 지방층 내부에 삽입되어 있는 단백질에 의해 조절된다.(중략)

• The Korean Journal of Zoology
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• v.32 no.4
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• pp.412-419
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• 1989

Monoclonal antibodies (MAbs) reacting with the plasmalemma of Amoeba proteus were produced. Specificity of the 3 MAbs was determined by transfer blotting of the SDS polvacryfamide gel. AMS antibody reacted with the mucopolysaccharide bands of the spacer gel, 220 KD and 50 KD proteins of the resolving gel. The maior glycoprotein bands (175 KD, 165 KD) and 50 KD protein of the plasmalemma were recognized by AUG antibody. A third, AMP antibody reacted with the 50 KD protein only. In immunofluorescence microscopy of the enzyme treated cells, the antigens of these MAbs were sensitive to proteases, but not sensitive to neuraminidase. In the assay of cell to substratum attachment after binding with the antibody, AMG and AMP antibodies exerted no effect, but AMS hindered the attachment and cell spreading. Thus the effective components of the plasmalemma in cell to substratum attachment appear to be the mucopolysaccharides and 220 KD protein. The membranes of latex particle infested phagosomes did not show any distinction from the plasmalemma in fluorescence microscopy. Phagosome membranes of amoebae appear to be derived from the plasma membrane without selection in terms of the antigen composition. Amoeba Proteus의 세포막과 반응하는 단세포군 항체를 생산하였다. SDS polyacrylamide gel을 transfer blotting하여 이들 항체의 반응 특이성을 조사해 본 결과 AMS 단항체는 PAS로 염색되는 spacer gel의 mucopolysaccharide 린드, resolving gel의 220 KD 및 50 KD 단백질과 반응하였으며, 세포막의 주요 당단백질인 175 KD 및 165 KD 빈드와 50 KD 단백질은 AMG 단항체에 의해서 인지되었다. 그리고 AMP단항체는 공통인 50 KD 단백질과 특이하게 반응하였다. 효소처리한 아메바의 면역형광칠미경적 조사에서 이들 항체에 대한 항원분자들은 모두 단백질분해효소에 민감하였으며 neuraminidase에 대해서는 변화가 없었다. 이들 항체를 결합시킨 아메바의 용기표면 부착 가능성을 분석한 결과 AMP 및 AMG 단항체는 아무런 영향을 미치지 못하였으며 AMS 단항체는 세포의 용기표면 부착 및 세포의 펴짐을 저해하였다. 따라서 아메바의 용기표면 부착은 mucopolysaccharide 및 220 KD 단백질에 의해서 매게되는 것으로 나타났다. 그리고 latex particle을 담고 있는 식포막은 면역형광형미경적 조사에서 세포막과 차이가 없었다. 따라서 겐포막은 항원 조성에 있어서 비 선택적으로 세포막에서 유도되는 것으로 나타났다.

• The Korean Journal of Zoology
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• v.35 no.2
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• pp.125-135
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• 1992

참개구리의 난자형성 단계에 따른 난황막의 구조적 변화와 막단백질의 변화에 대하여 연구함으로써 난자형성에 따른 난탈막의 기능적 분화의 가능성을 알아보고자 하T:다. 난황막의 구조적 변화는 난자형성에 따른 미세음모의 수와 모양의 변화로 확인되었다. 그 수가 초기에는 적으나 중기에 증가하고 알기에 다시 감소하며, 그 모양도 처음에는 킬고 가늘지만, 나중에는 짧고 굵어진다. 막단백질은 wheat germ agglutinin에 대해서만 특이하게 반응을 보이는 당단백질로서 작은 난모세포(직경 100-800 urn)와 큰 난모세포(직경 1500 urn)에서 다르게 나타난다. 분자량은 106 KD, 60 KD, 순 KD과 같이 어느 단계에서나 공통적으로 나타나는 단백질이 존재하는 반면에 특히 작은 난모세포의 난황막에서만 찾아 볼 수 있는 130 KD, 125 KD, 90 KD, 28 KD, 26KD과 같은 단겐 특이적으로 나타나는 막단백질도 있다. 이와 같은 결과로 미루어 보아 난황막 단백질은 난자형성단계에 따라 변화한다는 사실을 알 수 있다.

• Parasites, Hosts and Diseases
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• v.26 no.3
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• pp.155-162
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• 1988

Surface membrane proteins of virulent RH strain and tissue cyst-forming Fukaya strain of Toxoplasma gondii were analysed by SDS-polyacrylamide gel electrophoresis after LPO-catalyzed surface iodination and lectin blotting, then identified the zoite-specific antigens. Prior to the analyses, purification of RH tachyzoites from mouse peritoneal exudate and of Fukaya bradyzoites from mouse brain tissues were performed by centrifugation - on the discontinuous Percoll density-gradient. Ta- chysoites were obtained at the interface of 50U and 60% Percoll solution and brain cysts were harvested at the interfaces of 40-50% and 50-60%, then bradyzoites were obtained by treating the cysts with hypertonic solution. The LPO-catalyzed iodination detected 15 KDa and 14 KDa proteins o( brady- zoites and 30 KDa protein of tachysoites as major bands with several other minor bands. But Con A blotting revealed some bands of 200 K∼50 KDa glycoproteins of bradyzoites and 52 KDa band as major and minor bands of 33 K∼20 KDa of tachyzoites. Phytohemagglutinin did not detect any band in the two forms. EITB with anti- Fukaya antibody and anti-RH antibody revealed cross-reactivities between the two forms. Despite the cross-reactivity, anti-Fukaya antibody reacted with 15 KDa band of bradyzoites specifically and, anti-RH antibody with 52 KDa, 30 KDa, and 25 KDa bands of tachyzoites, respectively. It was identified that 15 KDa protein in bradyzoite, which was not a glycoprotein, was a major membrane protein with sufficient antigenicity, and in the case of tacky- zoite, 52 KDa surface glycoprotein (gp52) with specific antigenicity might be added to the major surface protein, p30.

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.163-177
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• 1988

The $Ca^{2+}-ATPase$ of sarcoplasmic reticulum (SR) was solubilized and reconstituted into a mixture of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) of varying ratios in order to assess the effect of physical states of phospholipids on the incorporation and functions $Ca^{2+}-ATPase$. On the basis of the spectral data of Ca-arsenazo III, the $Ca^{2+}$ uptake of SR was increased linearly as the PC content increased in the reconstituted vesicles. The ATP hydrolysis activity also increased as PC content increased up to 25% and then decreased slightly as the PC content further increased. On the other hand the incorporation of $Ca^{2+}-ATPase$ into the reconstituted vesicls occured maximally at 25% PC and 75% PE mixture which is known to have a non-bilayer structure in reconstitution system. From the above results it is clear that preexisting defects in the lipid bilayer promote protein incorporation into the bilayer during reconstitution and lamellar structure of the bilayer facilitates the $Ca^{2+}-ATPase$ function.

• Parasites, Hosts and Diseases
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• v.34 no.4
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• pp.215-224
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• 1996

actin and some actin binding proteins such as tropomyosin, α-actinin and troponin T were localized by simultaneous double immunogold labeling in several developmental stages of Cryptosporidium parvum. All of the observed developmental stages have many paricles of tropomyosin and actin around pellicle and cytoplasm. Tropomyosin was labeled much more than the actin when these two proteins were labeled simultaneously. And α-actinin was labeled mostly in the pellicle, but troponin T labeling weas very rarely observed. From this study it was suggested that tropomyosin seemed to be one of the major proteins of C. parvum, so it must be playing important roles in C. parvum.

• Journal of Yeungnam Medical Science
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• v.10 no.2
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• pp.360-368
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• 1993

GTP binding protein (G-protein) associated with membrane and involved in signal transduction was isolated from bovine brain, and molecular weight of G protein was observed. As the results, cell membranes were homogenized from bovine brain tissues and proteins of membrane were gained using 1% cholate, and progressed the chromatography. The purification process was performed by step, DEAE-Sephacel, Ulttrogel AcA 34 and heptylamine-Sepharose column chromatography. The chromatographic fractions were confirmed by GTP binding assay and SDS-polyacrylamide gel electrophoresis. Molecular weight of $Go{\alpha}$ was revealed 39,000 dalton and $G{\beta}$ 36,000 dalton. One more step of heptylamine-Sepharose was enforced to purify the GTP binding protein. Finally I gained the GTP binding protein isolated subtype of $Go{\alpha}$ and $G{\beta}$.