• 한국생물정보학회:학술대회논문집
• /
• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
• /
• pp.325-330
• /
• 2005

We are generally interested in the analysis, detection and prediction of structural motifs in proteins, in order to infer compatibility of amino acid sequence to structure in proteins of known three-dimensional structure available in the Protein Data Bank. In this context, we are analyzing some of the well-characterized structural motifs in proteins. We have analyzed simple structural motifs, such as, ${\beta}$-turns and ${\gamma}$-turns by evaluating the statistically significant type-dependent amino acid positional preferences in enlarged representative protein datasets and revised the amino acid preferences. In doing so, we identified a number of ‘unexpected’ isolated ${\beta}$-turns with a proline amino acid residue at the (i+2) position. We extended our study to the identification of multiple turns, continuous turns and to peptides that correspond to the combinations of individual ${\beta}$ and ${\gamma}$-turns in proteins and examined the hydrogen-bond interactions likely to stabilize these peptides. This led us to develop a database of structural motifs in proteins (DSMP) that would primarily allow us to make queries based on the various fields in the database for some well-characterized structural motifs, such as, helices, ${\beta}$-strands, turns, ${\beta}$-hairpins, ${\beta}$-${\alpha}$-${\beta}$, ${\psi}$-loops, ${\beta}$-sheets, disulphide bridges. We have recently implemented this information for all entries in the current PDB in a relational database called ODSMP using Oracle9i that is easy to update and maintain and added few additional structural motifs. We have also developed another relational database corresponding to amino acid sequences and their associated secondary structure for representative proteins in the PDB called PSSARD. This database allows flexible queries to be made on the compatibility of amino acid sequences in the PDB to ‘user-defined’ super-secondary structure conformation and vice-versa. Currently, we have extended this database to include nearly 23,000 protein crystal structures available in the PDB. Further, we have analyzed the ‘structural plasticity’ associated with the ${\beta}$-propeller structural motif We have developed a method to automatically detect ${\beta}$-propellers from the PDB codes. We evaluated the accuracy and consistency of predicting ${\beta}$ and ${\gamma}$-turns in proteins using the residue-coupled model. I will discuss results of our work and describe databases and software applications that have been developed.

• 대한의생명과학회지
• /
• 제12권2호
• /
• pp.73-79
• /
• 2006

Nebulin is a giant ($600{\sim}900$ kDa), modular sarcomeric protein proposed to regulate the assembly, and to specify the precise lengths of actin filamints in vertebrate skeletal muscles. Recently, There is an evidence that the nebulin also expressed in non muscle tissue, brain and liver. We identified a new isoform of nebulin from adult brain library by PCR screening. It contains two simple-repeats exon 165, 166 and linker-repeats exon $154{\sim}161$ except exon 159. The nebulin modules M160 to M170 (exon 150 to exon 161) has been shown to bind desmin. In mature striated muscle, desmin intermediate filaments surround Z-discs and link individual myofibrils laterally at their Z-discs and to other intracellular structures, including the costameres and the intercalated discs of the sarcolemma, sarcoplasmic reticulum, mitochondria, T-tubules, and nuclei. Therefore, it is an interesting possibility that the differential splice pathways within the linker region of nebulin modify the affinity of nebulin's interaction with desmin. The specific interactions of nebulin and desmin were confirmed in vivo by yeast two hybrid experiments. To verify in the cellular level the interaction between nebulin isoform and desmin, we transfected COS-7 cell with EGFP-tagged nebulin and DsRed-tagged desmin. Based on evidence showing that despite exon 159 was deleted, the new isoform of nebulin was interact with desmin. This suggest that nebulin in brain may interact with another intermediate filament. The conservation of these ligand-binding capacity in brain and skeletal nebulins suggest that nebulins may have conserved roles in brain and skeletal muscle.

• Applied Microscopy
• /
• 제23권1호
• /
• pp.35-55
• /
• 1993

cis-Dichlorodiammineplatinum (II) (cis-Platin), a metallic compound, has widely been used as an effective anticancer chemotherapeutic agent. The precise mechanism of action of this agent is still unknown, but it is postulated that cis-Platin may act on the cancer cell like bifunctional alkylating agents. Although this agent is very beneficial to the patients with cervical cancer, germinoma of testis, neuroblastoma and others, it may also damage to the normal cell so that many side effects; severe hemorrhagic enterocolitis, bone marrow depression, renal damage and liver damage will develope. This experiment has been undertaken to pursue the cytotoxic effects of the cis-Platin on the ultrastructures of the interalveolar septum in the mouse lung. A total of 55 healthy male mice of ICR strain were used as experimental animals and divided into 5 mice of normal control group and 50 mice of cis-Platin treated group. The mice of cis-Platin treated group were sacrificed by carotid exsanguination at 6, 12, 24 hours, 3 days and 7 days after intraperitoneal injection of 6.0 mg of cis-Platin ($Abiplatin^R$ Abic Co. Ltd.) per kg of mouse body weight. The specimen obtained from the lower lobe of left lung were sliced into $1mm^3$ and prefixed with 2% glutaraldehyde -2.5% paraformaldehyde solution prepared with Millonig's phosphatae buffer solution (pH 7.4) at $4^{\circ}C$ for 3-4 hours. After postfixation with 1% osmium tetroxide solution all specimens were embedded in Epon 812. Ultrathin sections about $600-800{\AA}$ in thickness were stained with uranyl acetate and lead citrate and observed with Hitachi-600 electron microscope. The results obtained were as follows: 1. Local swellings with increase of electron density and number of pinocytic vesicles in the cytoplasms of the type I pneumocyte and endothelial cell of the blood air barrier in interalveolar septum of cis-platin treated mice were observed. 2. Cisternae of rough endoplasmic reticulum were dilated and sacculated in association with detachment of membrane bound ribosomes of the type II pneumocyte in interalveolar septum of cis-Platin treated mice. 3. Swollon mitochondria with uneven electron density of their matrix were observed in the type II pneumocyte of interalveolar septum in the cis-Platin treated mice. 4. The lamellae of lammelar bodies in type II pneumocyte of interalveolar septum in cis-Platin treated mice were devoided or transformed into homogeneous electron dense material. It is consequently suggested that cis-Platin would induce the cellular edema of type I pneumocyte and endothelial cell, and degenerative changes of cytoplasmic organelles of the type II pneumocyte in the interalveolar septum of the mouse lung.

• Applied Biological Chemistry
• /
• 제29권4호
• /
• pp.359-365
• /
• 1986

대수증식(代數增殖) 중기(中期)의 S. cerevisiae에 $2{\times}10^{-3}M$의 paraquat를 처리(處理)하여 균체(菌體) 증식(增殖), 균체(菌體)의 일반적(一般的)형태 및 미세구조(微細構造)에 미치는 영향을 검토하였다. 균체(菌體)의 증식(增殖)은 Paraquat 처리(處理) 후(後) 조해(阻害)되기 시작하여 처리(處理) 6시간(時間) 이후(以後) 완전(完全)히 조해(阻害)되었다. 이 기간동안 탁도(濁度)는 0. 1에서 3.6으로, 건물(乾物) 중량(中量) 1ml당 2.75mg으로부터 3.35mg으로, 총균수(總菌數)는 ml당2 $1.14{\times}10^8cell$로부터 $2.15{\times}10^8cell$로 증가(增加)되었으나 6시간(時間) 이상(以上) 처리시간(處理時間)이 길어짐에 따라 역(逆)으로 감소되었고 사균율(死菌率)은 초기의 0.28%로부터 6시간(時間)째에는 5%, 12시간(時間)째에는 72%로 계속 증가(增加)되었다. Paraquat 처리(處理)에 의하여 균체(菌體)의 크기가 균일(均一)치 못하게 되었으며 세포벽(細胞壁)의 두께가 $0.15{\mu}m$(대조구(對照區) $0.20{\mu}m$)로 얇아지는 반면에 외측(外側)의 전자(電子)밀도가 높아졌으며 12시간(時間) 이상(以上)의 처리(處理)에 의하여 원형질막(原形質膜) 및 mitochondria와 같은 내막구조(內膜構造)가 와해되었다.

• 대한화장품학회지
• /
• 제43권1호
• /
• pp.53-60
• /
• 2017

본 연구에서는 수박 덩굴(잎 및 줄기) 추출물 및 용매 분획물의 미백 및 항염 활성을 검색하고 유효성분을 분리하여 화학구조를 규명하였다. 수박 덩굴 에탄올 추출물 및 용매 분획물의 멜라닌 생성 억제활성을 측정한 결과, 헥산 및 에틸아세테이트 분획물에서 우수한 멜라닌 생성 억제 효과가 있음을 확인하였다. 또한 항염 활성측정 결과, 헥산 및 에틸아세테이트 분획물에서 활성이 나타남을 확인하였다. 헥산 및 에틸아세테이트 분획물에서 유효성분을 찾고자 칼럼 크로마토그라피를 실시하여 3개의 화합물을 분리하였으며 $^1H$ 및 $^{13}C$ NMR 데이터 분석 및 문헌치 비교를 통하여 화학구조를 동정하였다; ${\alpha}-linolenic$ acid (1), sigmast-7-en-O-${\beta}$-D-glucopyranoside (2), 1-feruloyl-${\beta}$-D-glucopyranoside (3). 분리된 화합물에 대한 미백 활성 실험 결과, 화합물 1과 3에서 멜라닌 생성 및 세포 내 티로시나제 효소의 활성을 감소시키고 있음을 확인하였다. 또한 항염 활성 실험 결과 화합물 1과 3이 nitric oxide (NO) 및 전염증성 사이토카인($TNF-{\alpha}$, IL-6)의 생성을 억제시킴을 확인하였다. 이상의 연구 결과를 바탕으로 수박 덩굴 추출물을 이용한 천연 미백 및 항염 소재로의 개발이 가능할 것이라 사료된다.

• Parasites, Hosts and Diseases
• /
• 제54권6호
• /
• pp.725-732
• /
• 2016

Plasmodium vivax produces numerous caveola-vesicle complex (CVC) structures beneath the membrane of infected erythrocytes. Recently, a member helical interspersed subtelomeric (PHIST) superfamily protein, $PcyPHIST/CVC-81_{95}$, was identified as CVCs-associated protein in Plasmodium cynomolgi and essential for survival of this parasite. Very little information has been documented to date about $PHIST/CVC-81_{95}$ protein in P. vivax. In this study, the recombinant $PvPHIST/CVC-81_{95}$ N and C termini were expressed, and immunoreactivity was assessed using confirmed vivax malaria patients sera by protein microarray. The subcellular localization of $PvPHIST/CVC-81_{95}$ N and C termini in blood stage parasites was also determined. The antigenicity of recombinant $PvPHIST/CVC-81_{95}$ N and C terminal proteins were analyzed by using serum samples from the Republic of Korea. The results showed that immunoreactivities to these proteins had 61% and 43% sensitivity and 96.9% and 93.8% specificity, respectively. The N terminal of $PvPHIST/CVC-81_{95}$ which contains transmembrane domain and export motif (PEXEL; RxLxE/Q/D) produced CVCs location throughout the erythrocytic-stage parasites. However, no fluorescence was detected with antibodies against C terminal fragment of $PvPHIST/CVC-81_{95}$. These results suggest that the $PvPHIST/CVC-81_{95}$ is localized on the CVCs and may be immunogenic in natural infection of P. vivax.

• Applied Microscopy
• /
• 제25권4호
• /
• pp.52-61
• /
• 1995

CAM대사를 수행하는 것으로 추정되는 한국산 바위솔속식물 3종(난장이바위솔, 바위솔, 둥근바위솔)의 엽육조직이 전자현미경적으로 연구되었다. 다육질성의 이들 엽육조직은 주로 세포의 크기가 큰 수분저장 세포들로 구성되어 있고 세포간극이 잘 발달되어 있다. 세포내 또는 세포간극에는 점액성 분비물질들이 분포하였다. 수분저장 세포에는 하나 또는 여러 개의 큰 액포가 있고 이들이 세포체적의 대부분을 차지하여 세포질은 세포벽 주위에서 매우 적게 분산되어 나타났다. 세포질내에는 다수의 엽록체, 미소체, 미토콘드리아, 소포체, 골지체 등의 전형적인 세포소기관외에 엽록체주변에서 관찰되는 세포질의 특이한 분포양상을 비롯하여 세포벽과 분리되어 나타나는 파상(undulation or invagination)의 세포막과 이중막으로 둘러싸인 원형질막 기원소포(plasmalemmasome)및 수초상구조(myelin-like structure), 액포상구조(vacuole-like structure) 또는 낭상구조(bladder-like structure) 등이 발견되었다. 특히 파상의 세포막 및 액포막의 신장으로 형성된 액포상 또는 낭상구조와 엽록체주변 세포질의 특이한 분포양상 등은 주목할 만한 것으로 이들의 특성 및 구조는 CAM대사와 연계되어 자세히 연구되어야 할 것이다. 이와 같은 엽육조직의 구성 및 미세구조적 특성으로 보아 본 바위솔속 식물들은 CAM대사를 수행하는 식물군으로 사료된다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권7호
• /
• pp.3519-3528
• /
• 2012

Inhibitory effects of Maclura amboinenesis Bl, one plant used traditionally for the treatment of cancers, on metastatic potential of highly metastatic B16F10 melanoma cells were investigated in vitro. Cell proliferation was assessed using the MTT colorimetric assay. Details of metastatic capabilities including invasion, migration and adhesion of B16F10 melanoma cells were examined by Boyden Chamber invasion and migration, scratch motility and cell attachment assays, respectively. The results demonstrated that n-hexane and chloroform extracts exhibited potent anti-proliferative effects (p<0.01), whereas the methanol and aqueous extracts had less pronounced effects after 24 h exposure. Bioactivity-guided chromatographic fractionation of both active n-hexane and chloroform extracts led to the isolation of two main prenylated xanthones and characterization as macluraxanthone and gerontoxanthone-I, respectively, their structures being identified by comparison with the spectral data. Interestingly, both exhibited potent effective effects. At non-toxic effective doses, n-hexane and chloroform extracts (10 and $30{\mu}g/ml$) as well as macluraxanthone and gerontoxanthone-I (3 and $10{\mu}M$) significantly inhibited B16F10 cell invasion, to a greater extent than $10{\mu}m$ doxorubicin, while reducing migration of cancer cells without cellular cytotoxicity. Moreover, exposure of B16F10 melanoma cells to high concentrations of chloroform ($30{\mu}g/ml$) and geratoxanthone-I ($20{\mu}M$) for 24 h resulted in delayed adhesion and retarded colonization. As insights into mechanisms of action, typical morphological changes of apoptotic cells e.g. membrane blebbing, chromatin condensation, nuclear fragmentation, apoptotic bodies and loss of adhesion as well as cell cycle arrest in the G1 phase with increase of sub-G1 cell proportions, detected by Hoechst 33342 staining and flow cytometry were observed, suggesting DNA damage and subsequent apoptotic cell death. Taken together, our findings indicate for the first time that active n-hexane and chloroform extracts as well as macluraxanthone and gerontoxanthone-I isolated from Maclura amboinensis Bl. roots affect multistep of cancer metastasis processes including proliferation, adhesion, invasion and migration, possibly through induction of apoptosis of highly metastatic B16F10 melanoma cells. Based on these data, M. amboinensis Bl. represents a potential candidate novel chemopreventive and/or chemotherapeutic agent. Additionally, they also support its ethno-medicinal usage for cancer prevention and/or chemotherapy.

• 한국임상수의학회지
• /
• 제30권4호
• /
• pp.292-295
• /
• 2013

9세령의 수컷 도베르만견이 5개월간 간헐적인 혈뇨, 구토 및 당뇨증상을 보여 동물병원에 내원하였다. 초음파상에서 종대된 좌측 신장의 수질부위에 종괴가 발견되었다. 육안적으로 좌측 신장의 피질 및 수질부는 현저하게 위축되어 있었으며 신우 부위는 종괴로 인하여 확장된 수신증을 나타내었다. 크기 4~5.5 cm의 유두상으로 돌출된 꽃자루와 같은 단일종괴가 신우 부위에 있으며, 요관으로 뻗어 있었다. 병리조직학적으로 종괴는 나뭇가지 모양으로 무수히 돌출된 유두상의 돌기들로 구성되어 있었다. 이 돌기들은 섬유혈관성 중심부와 뚜렷한 이형태성을 가지는 여러 층의 종양화된 이행상피들로 피복되어 있었다. 면역조직화학염색을 실시한 결과 종양세포들은 사이토케라틴(cytokeratin: CK) 7, 19, CK clone MNF116 및 CK HMW에 대해서 양성을 보였으나 CK 8 LMW에서는 음성 반응을 나타내었다. 육안적인 특징, 병리조직학적 소견 및 면역조직화학염색에 의한 사이토케라틴의 반응성을 토대로 이 종괴는 개의 신우에서 발생한 이행상피암종으로 진단되었다.

• 공업화학
• /
• 제23권5호
• /
• pp.467-473
• /
• 2012

본 연구에서는 레시틴, 에탄올, 오일, Arlacel 60 (sorbitan monostearate) 등을 주성분으로 하고, 최근 화장품과 식품의 원료로서 각광을 받고 있는 피부의 노화방지용 항산화물질인 코엔자임 Q10 (CoQ10)를 기능성 원료로 함유하는 나노 에멀젼을 제조하고자 하였다. 에멀젼 제조방법으로는 반전유화법(phase inversion emulsion method)과 초음파를 이용한 기계적 방법을 사용하였으며, 이 때 에탄올과 레시틴의 영향과 시간의 경과에 따른 안정성과 그 밖의 각종 변수들이 미치는 영향을 알아보고자 하였다. 이를 위하여 입자의 크기, 제타전위, 에멀젼의 형태와 같은 물리적 특성들을 측정해 보았다. 최소크기의 나노에멀젼을 형성하기 위한 CoQ10의 최적 배합농도는 0.8% 정도였고, 계면활성제로서 Arlacel 60 농도에 따른 입자크기의 영향을 보면 3% 정도에서 100 nm 크기의 에멀젼 입자들을 얻을 수 있었다. 본 연구에서의 사용한 최적의 계면활성제 농도범위(2% 이상)에서는 7일 정도가 지난 시점까지 Ostwald ripening 에 따른 입자의 크기 변화가 없었다. 장시간의 경과에 따른 실험을 보면 에멀젼들은 실온에서 270일이 지난 상태에서도 115 nm로 10% 정도만의 크기 변화를 보여 비교적 안정된 상태로 에멀젼을 유지함을 알 수 있었으며, 제타전위 측정으로 시간의 경과에 따른 입자크기의 변화는 응집(flocculation)에 기인한 것으로 판단된다.