• Title/Summary/Keyword: Small protein

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Biopharmaceutical studies on copper(II) chelates of sulfanilamide derivatives (Sulfanilamide유도체의 동(II)착화합물에 대한 생물약제학적 연구)

  • 김재백
    • YAKHAK HOEJI
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    • v.15 no.2
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    • pp.41-52
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    • 1971
  • Cu(II) chelates of several sulfanilamide derivatives (Sulfa-Cu) were prepared and their effects on solubility, absorptivity in intestinal lumen, biding tendency with serum protein and erythrocytes, concentration in rabbit blood, and acetylation rate were studied in comparison with their free ligand forms. For solubility concerned, the partition coefficients of Sulfa-Cu are decreased as following order: Sulfadimethoxine Copper chelate (SDM-Cu), Sulfamethoxypyridazine Copper chelate (SD-Cu), Sulfamerazine Copper chelate (SM-Cu), Sulfaisoxazole Copper chelate (SIX-Cu). The partition coefficients of SDM-Cu and ST-Cu were much greater than those of ligands. this phenomenone acounts for the rapid absorption of SDM-Cu and ST-Cu in the rat small intestine (in situ). The Sulfa-Cu were absorbed at the intestinal lumen of a rat in the rate of first order and there was no difference between long acting sulfa drugs and their Cu0chelates in biological half lives. In binding experiments, sulfa-Cu binded with serum protein in lower ratio than their ligands except SIX-Cu. On other hand, acetylation rates of sulfa-Cu were higher than those of free sulfa drugs and the acetylation rate were higher than those of free sulfa drugs and powder. In a experiment on Sulfa-Cu concentration in rabbit blood, the half lives of SD-Cu, SIX-cu, ST-Cu, and SM-Cu were longer than those of their ligands. Above all, the half life of SD-Cu appeared to be approximately 3.5 times logner than that of corresponding ligand, SD. When absorption of sulfa drugs or sulfa-Cu at the small intestinal lumen of a rat and the concentration in rabbit blood after absorption were compared, it was found that there was not always conrrelated.

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A Study of the Retention Behavior of Proteins in High-Performance Liquid Chromatography(Ⅰ): The Effect of Solvent and Temperature on Retention Behavior of Proteins in Reversed-Phase Chromatography

  • Dai Woon Lee;Byung Yun Cho
    • Bulletin of the Korean Chemical Society
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    • v.14 no.4
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    • pp.510-514
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    • 1993
  • The retention behavior of proteins was investigated by using reversed-phase chromatography (RPC), comparing to the retention behavior of small molecules in RPC. The evaluation was carried out on a SynChropak RP-P($C_{18}$) column with 0.1% aq. TFA-organic solvent modifier such as acetonitrile, isopropanol, and ethanol. The Z value (the number of solvent molecules required to displace the solute from the surface) was a general index for the characterization of protein retention as a function of organic concentration over a range of temperature between 5 and 70$^{\circ}C$. Van't Hoff plots provided the basis for evaluating the enthalpic and entropic changes associated with the interaction between protein and the stationary phase. Z values did not change significantly at the range of temperature showing the consistent ${\Delta}H^{\circ}$ and ${\Delta}S^{\circ}$ values. From these investigation, it was concluded that the retention behavior of proteins in RPC was able to be predicted by the retention parameters applied to small molecules. Furthermore, myoglobin and hemoglobin in RPC as stated above showed a similar retention behavior regardless of their molecular weights.

In-silico Modeling of Chemokine Receptor CCR2 And CCR5 to Assist the Design of Effective and Selective Antagonists

  • Kothandan, Gugan;Cho, Seung Joo
    • Journal of Integrative Natural Science
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    • v.5 no.1
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    • pp.32-37
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    • 2012
  • Chemokine receptor antagonists have potential applications in field of drug discovery. Although the chemokine receptors are G-protein-coupled receptors, their cognate ligands are small proteins (8 to 12 kDa), and so inhibiting the ligand/receptor interaction has been challenging. The application of structure-based in-silico methods to drug discovery is still considered a major challenge, especially when the x-ray structure of the target protein is unknown. Such is the case with human CCR2 and CCR5, the most important members of the chemokine receptor family and also a potential drug target. Herein, we review the success stories of combined receptor modeling/mutagenesis approach to probe the allosteric nature of chemokine receptor binding by small molecule antagonists for CCR2 and CCR5 using Rhodopsin as template. We also urged the importance of recently available ${\beta}2$-andrenergic receptor as an alternate template to guide mutagenesis. The results demonstrate the usefulness and robustness of in-silico 3D models. These models could also be useful for the design of novel and potent CCR2 and CCR5 antagonists using structure based drug design.

Reliable Identification of Bacillus cereus Group Species Using Low Mass Biomarkers by MALDI-TOF MS

  • Ha, Miyoung;Jo, Hyeon-Ju;Choi, Eun-Kyeong;Kim, Yangsun;Kim, Junsung;Cho, Hyeon-Jong
    • Journal of Microbiology and Biotechnology
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    • v.29 no.6
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    • pp.887-896
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    • 2019
  • Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based pathogen identification relies on the ribosomal protein spectra provided in the proprietary database. Although these mass spectra can discern various pathogens at species level, the spectra-based method still has limitations in identifying closely-related microbial species. In this study, to overcome the limits of the current MALDI-TOF MS identification method using ribosomal protein spectra, we applied MALDI-TOF MS of low-mass profiling to the identification of two genetically related Bacillus species, the food-borne pathogen Bacillus cereus, and the insect pathogen Bacillus thuringiensis. The mass spectra of small molecules from 17 type strains of two bacilli were compared to the morphological, biochemical, and genetic identification methods of pathogens. The specific mass peaks in the low-mass range (m/z 500-3,000) successfully identified various closely-related strains belonging to these two reference species. The intensity profiles of the MALDI-TOF mass spectra clearly revealed the differences between the two genetically-related species at strain level. We suggest that small molecules with low molecular weight, 714.2 and 906.5 m/z can be potential mass biomarkers used for reliable identification of B. cereus and B. thuringiensis.

Association of p53 Expression with Metabolic Features of Stage I Non-Small Cell Lung Cancer

  • Kang, Shin-Myung;Koh, Won-Jung;Suh, Gee-Young;Chung, Man-Pyo;Han, Joung-Ho;Kim, Ho-Joong;Kwon, O-Jung;Um, Sang-Won
    • Tuberculosis and Respiratory Diseases
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    • v.71 no.6
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    • pp.417-424
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    • 2011
  • Background: Recent evidences have revealed metabolic functions of p53 in cancer cells; adaptation or survival to metabolic stress and metabolic shift toward oxidative phosphorylation. However, further studies in clinical setting are needed. We investigated whether p53 protein expression, as a surrogate marker for loss of p53 function, is associated with metabolic features of stage I non-small cell lung cancer (NSCLC), focusing on tumor necrosis and maximal standardized uptake value (SUVmax) on $^{18}F$-fluorodeoxyglucose positron emission tomography. Methods: Clinical information was obtained from retrospective review of medical records. p53 expression was assessed by immunohistochemical staining. Results: p53 protein expression was detected in 112 (46%) of 241 NSCLC cases included in this study. p53 expression was independently associated with the presence of necrosis (odds ratio [OR], 2.316; 95% confidence interval [CI], 1.215~4.416; p=0.011). Non-adenocarcinoma histology (OR, 8.049; 95% CI, 4.072~15.911; p<0.001) and poorly differentiation (OR, 6.474; 95% CI, 2.998~13.979; p<0.001) were also independently associated with the presence of necrosis. However, p53 expression was not a significant factor for SUVmax. Conclusion: p53 protein expression is independently associated with the presence of necrosis, but not SUVmax.

Effects of Orotic Acid and Di-(2-Ethylhexyl)Phthalate on Microsomal Triglyceride Transfer Protein(MTP) Activity and mRNA Levels in Liver and Intestine of Rats (Orotic acid와 Di-(2-ethylhexyl)phthalate 투여 흰쥐의 간장 및 소장 Microsomal Triglyceride Transfer Protein(MTP) 활성과 mRNA 수준에 미치는 영향)

  • Cha, Jae-Young;Cho, Young-Su
    • Korean Journal of Food Science and Technology
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    • v.33 no.4
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    • pp.492-496
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    • 2001
  • Microsomal triglyceride transfer protein(MTP) activity and mRNA level were investigated in the liver and small intestine of rats fed on di-(2-ethylhexyl)phthalate(DEHP) and orotic acid(OA) as serum triglyceride-reducing agents. The concentration of liver triglyceride was significantly increased in the OA group, but that was not increased in the DEHP group compared with the control group. The concentration of serum triglyceride was significantly decreased in the OA and DEHP groups compared with the control group, but this reduction was more pronounced in the OA group. MTP activity and mRNA level in liver were decreased in the OA group compared with the control group, while MTP activity in the small intestine was increased in the OA group compared with the control group. MTP activities and MTP mRNA levels in both liver and small intestine had no influence by the DEHP dietary feeding, despite the triglyceride-lowering action, compared with the control dietary feeding. The activity of liver microsomal phosphatidate phosphohydrolase(PAP), the rate-limiting enzyme in triglyceride synthesis, was increased in the OA group compared with the control group, but that of cytosolic PAP was decreased in the DEHP group compared with the control group. The result suggest that MTP activity and MTP mRNA level are involved in the triglyceride-lowering action of OA, but those are not involved in that of DEHP.

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Effect of Transcriptional Terminator Sequences on Recombinant Protein Expression from Drosophila melanogaster S2 Cell (전사 종결 염기 서열이 Drosophila melanogaster Schneider line 2 세포에서 외래 단백질의 발현에 미치는 영향)

  • Hwang, In-Sook;Park, Jong-Hwa;Lee, Youn-Hyung;Yoon, Jae-Seung;Baek, Kwang-Hee;Chung, In-Sik
    • Applied Biological Chemistry
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    • v.44 no.4
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    • pp.211-214
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    • 2001
  • Utilizing the foreign gene expression system of Drosophila melanogaster Schneider line 2(S2) cell, the degree of transient protein and mRNA expression was examined with different terminators. In the case of transient expression, the expression level of green fluorescent protein(GFP) was the highest when the transfection agent was eliminated and then cultivated for 36 to 48 hr. The terminators(SV40 p(A), SV40 small T-antigen and human gastrin 3'UTR) of the expression vector system were each cloned with endostatin; thereafter, the expression levels of the endostatin and its mRNA were compared. When the expression levels of endostatin were compared 36 hr after transfection, the SV40 p(A) terminator showed the highest expression level of endostatin and its mRNA.

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The Clinical and Pathologic Features according to Expression of Acyl Protein Thioesterase-1 (APT1) in Stage I Non-small Cell Lung Cancer (제1기 비소세포폐암에서 APT1 발현의 임상적 의미)

  • Shin, Jung-Ar;Lee, Chang-Ryul;Byun, Min-Kwang;Chang, Yoon-Soo;Kim, Se-Kyu;Chang, Joon;Ahn, Chul-Min;Kim, Hyung-Jung
    • Tuberculosis and Respiratory Diseases
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    • v.68 no.4
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    • pp.212-217
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    • 2010
  • Background: Acyl protein thioesterase-1 (APT1) is a cytosolic protein that may function in the depalmitoylation of numerous proteins, including the Ras family. However, the clinical role of depalmitoyl thioesterase in human cancer is not known. We evaluated the APT1 expression in lung cancer tissue and its clinicopathological findings according APT1 expression pattern. Methods: APT1 expression was examined by immunohistochemistry in the tumor tissue from 79 patients, who had undergone curative surgical removal of the primary lesion; all patients had been diagnosed with stage I non-small cell lung cancer between 1993 and 2004, at Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. Results: The APT1 expression was seen in 50 out of 79 (63.3%) cases. The positive APT1 expression was significantly related with histologic subtype and T stage, but was not influenced by differentiation. The positive APT1 expression was not significantly related to patient age, gender, or smoking history. The median follow-up duration was 10.0 years; the 5-year survival rate was 71.0%. The positive APT1 expression group showed significantly worse overall survival and worse disease-free survival without statistical significance. Conclusion: We conclude that positive APT1 expression in stage I lung cancer after surgery is closely associated with overall survival. To evaluate APT1 as a prognostic marker in lung cancer, comprehensive studies on advanced stage cases are needed.

Transcriptional Modulation of Metabolism-Related Genes in Brackish Water Flea Diaphanosoma celebensis Exposed to Mercury (수은 노출에 따른 기수산 물벼룩의 대사 관련 유전자의 발현 양상)

  • Min Jeong, Jeon;Je-Won, Yoo;Young-Mi, Lee
    • Journal of Marine Life Science
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    • v.7 no.2
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    • pp.145-153
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    • 2022
  • Mercury (Hg) is a major concern in marine environment because of their bioaccumulation and biomagnification properties, and adverse effects to aquatic organisms at even a trace amount. However, little information on the effects of Hg, compared to other heavy metals, is available in marine small crustaceans. Here, we investigated the transcriptional modulation of metabolism-related genes in the brackish water flea, Diaphanosoma celebensis after exposure to sublethal concentration (0.2, 0.4, 0.8 ㎍/l) of HgCl2 for 48 h. Relative mRNA expression levels of five detoxification enzyme-coding genes (cytochrome P450; cyp360A1, cyp361A1, cyp4AP3, cyp4C122, and cyp370C5) and six digestive enzyme-coding genes [alpha amylase (AMY), alpha amylase related protein (AMY-like), trypsin (TRYP), chymotrypsin-like protein (CHY), lipase (LIP), pancreatic lipase-related protein (PLRP)] were analyzed using quantitative real time reverse transcription polymerase chain reaction (qRT-PCR). As results, Hg increased the mRNA level of cyp370C5 (clan2) and cyp4AP3 (clan4) in a concentration dependent manner. A significant increase in TRYP mRNA was also concentration-dependently observed after exposure to Hg. These findings suggest that cyp370C5 and cyp4AP3 play a key role in Hg detoxification in D. celebensis, and Hg can affect energy metabolism by modulating the transcription of digestive enzyme. This study will provide better understanding the molecular effects of Hg in marine small crustacean.

DNA Binding Mode of the Isoquinoline Alkaloid Berberine with the Deoxyoligonucleotide d(GCCGTCGTTTTACA)2

  • Park, Hye-Seo;Kim, Eun-Hee;Sung, Yoon-Hui;Kang, Mi-Ran;Chung, In-Kwon;Cheong, Chae-Joon;Lee, Weon-Tae
    • Bulletin of the Korean Chemical Society
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    • v.25 no.4
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    • pp.539-544
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    • 2004
  • The ability of protoberberine alkaloids, berberine and berberrubine, to act as topoisomerase II poisons is linked to the anti-cancer activity. Minor alterations in structure have a significant effect on their relative activity. Berberine, which has methoxy group at the 19-position, is significantly less potent than berberrubine. Several observations support non-specific binding to HP14 by the berberine: (i) nonspecific upfield changes in $^1H$ chemical shift for protons of the berberine; (ii) the broadening of imino protons of HP14 upon binding of the berberine; (iii) very small increases in duplex melting temperature in the presence of the berberine. Our results reveal that substitution of a hydroxyl group to a methoxy group on the 19-position, thereby converting the berberrubine to the berberine is associated with a non-specific DNA binding affinity and a reduced topoisomerase II poisoning. The presence of a bulky 19-methoxy substituent decreases intercalating properties of berberine and makes it inactive as topoisomerase II poison.