• Title/Summary/Keyword: Glycoprotein (G)

Search Result 200, Processing Time 0.028 seconds

Purification of Egg Immunoglobulin IgY (계란 면역 단백질[IgY]의 정제 연구)

  • Kim, In-Ho;Lee, Yong-Tak;Lee, Chung-Hee;Chung, Bong-Hyun
    • KSBB Journal
    • /
    • v.14 no.6
    • /
    • pp.677-681
    • /
    • 1999
  • Purificationi of egg yolk immunoglobulin(IgY) was performed to understand the property of egg immunoglobulin. IgY differs from mammalian IgY in the molecular size(larger), isoelectric point(more acidic), and binding ability with mammalian complement and protein A(nonbinding ability). IgY is also known as ${\gamma}$-livetin and exists in egg yolk together with other two water-solubel proteins, ${\alpha}$-livetin(chicken serum albumin) and ${\beta}$-livetin(${\alpha}_2$-glycoprotein) and various lipoproteins(Low density lipoprotein, LDL and High density lipoprotein, HDL) which are the major components of egg yolk. The first step of isolation of IgY is to separate the water-solube proteins from lipoproteins. We report a simple method for separation of water soluble proteins using k-carrageenan and sedimentation. k-carrageenan was found to be effective for removal of yolk lipoprotein as a precipitate. IgY remained supernatant, and was isolated by chromatography on columns of DEAE-Sephacel and G 75 gel filtration chromatography.

  • PDF

Antiviral activity of sertindole, raloxifene and ibutamoren against transcription and replication-competent Ebola virus-like particles

  • Yoon, Yi-Seul;Jang, Yejin;Hoenen, Thomas;Shin, Heegwon;Lee, Younghoon;Kim, Meehyein
    • BMB Reports
    • /
    • v.53 no.3
    • /
    • pp.166-171
    • /
    • 2020
  • A chemical library comprising 2,354 drug-like compounds was screened using a transcription and replication-competent viruslike particle (trVLP) system implementing the whole Ebola virus (EBOV) life cycle. Dose-dependent inhibition of Ebola trVLP replication was induced by 15 hit compounds, which primarily target different types of G protein-coupled receptors (GPCRs). Based on the chemical structure, the compounds were divided into three groups, diphenylmethane derivatives, promazine derivatives and chemicals with no conserved skeletons. The third group included sertindole, raloxifene, and ibutamoren showing prominent antiviral effects in cells. They downregulated the expression of viral proteins, including the VP40 matrix protein and the envelope glycoprotein. They also reduced the amount of EBOV-derived tetracistronic minigenome RNA incorporated into progeny trVLPs in the culture supernatant. Particularly, ibutamoren, which is a known agonist of growth hormone secretagogue receptor (GHSR), showed the most promising antiviral activity with a 50% effective concentration of 0.2 μM, a 50% cytotoxic concentration of 42.4 μM, and a selectivity index of 222.8. Here, we suggest a strategy for development of anti-EBOV therapeutics by adopting GHSR agonists as hit compounds.

Clinical Application of Serum Tumor Abnormal Protein from Patients with Gastric Cancer

  • Liu, Jin;Huang, Xin-En
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.9
    • /
    • pp.4041-4044
    • /
    • 2015
  • Background: To verify whether serum tumor abnormal protein (TAP) would correlate with the responsiveness of palliative chemotherapy in patients with advanced gastric cancer, and the variation of conventional serum tumor markers e.g., carcinoembryonic antigen (CEA), antigen 125 (CA125),carbohydrate antigen19-9 (CA19-9) of adjuvant chemotherapy in patients with early gastric cancer. Materials and Methods: Patients with histologically confirmed gastric cancer and treated with chemotherapy were enrolled into this study. TAP values of these patients were determined by detecting abnormal sugar chain glycoprotein in serum, combined with the area of agglomerated particles. For patients with advanced gastric cancer, responsiveness of palliative chemotherapy was compared with variation of TAP and the relation between variation of TAP and tumor markers in patients with early gastric cancer was analyzed. Results: Totally 82 gastric cancer patients were enrolled into this study. The value of TAP is more closely related to responsiveness of palliative chemotherapy for patients with advanced gastric cancer. The correlation between TAP and responsiveness to palliative chemotherapy is stronger than the correlation between several conventional serum tumor markers (CEA, CA125 and CA199). The variation of TAP was also positively correlated with the trend of CA125 in adjuvant chemotherapy. Conclusions: TAP is sensitive in monitoring the responsiveness to palliative chemotherapy in patients with advanced gastric cancer. But this result should be confirmed by randomized clinical trials for patients with gastric cancer.

Subcutaneous Four-Week Repeated Dose Toxicity Studies of Rice Cell-Derived Recombinant Human Granulocyte-Macrophage Colony Stimulating Factor in Rats

  • Ji, Jung-Eun;Lee, Jung-Min;Choi, Jong-Min;Choi, Young-Hwa;Kim, Eun-Kyung;Chu, So-Jung;Kim, Seok-Kyun;Ahn, Kyong-Hoon;Lee, Dong-Hoon;Kim, Ha-Hyung;Han, Kyu-Boem;Kim, Dae-Kyong
    • Toxicological Research
    • /
    • v.24 no.4
    • /
    • pp.315-320
    • /
    • 2008
  • Recombinant human granulocyte-macrophage colony stimulating factor (hGM-CSF) is a glycoprotein and hematopoietic growth factors that regulates the proliferation of myeloid precursor cells and activates mature granulocytes and macrophages. In a previous study, we reported that hGM-CSF could be produced in transgenic rice cell suspension culture, termed rhGM-CSF. In the present study, we examined the repeated dose toxicity of rhGM-CSF in SD rats. The repeated dose toxicity study was performed at each dose of 50 and 200 ${\mu}g/kg$ subcutaneous administration of rhGM-CSF everyday for 28-days period. The results did not show any changes in food and water intake. There were also no significant changes in both body and organ weights between the control and the tested groups. The hematological and blood biochemical parameters were statistically not different in all groups. These results suggest that rhGM-CSF may show no repeated dose toxicity in SD rats under the conditions.

Cloning and Characterization of the IgA Fc Receptor from Swine

  • Chen, Yumei;Liu, Yunchao;Zhang, Gaiping;Feng, Hua;Ji, Pengchao;Wang, Guoqiang;Liu, Chang;Song, Yapeng;Su, Yunfang;Qiao, Songlin;Wang, Aiping
    • Journal of Microbiology and Biotechnology
    • /
    • v.26 no.12
    • /
    • pp.2192-2198
    • /
    • 2016
  • The myeloid-specific IgA Fc receptor ($Fc{\alpha}R$) is a cell surface molecule on immunocytes that provides a fundamental connection between humoral and cellular immunity. In this study, the full-length cDNA sequence of swine $Fc{\alpha}RI$ ($swFc{\alpha}RI$) was isolated and characterized and found to contain a 792-base-pair open reading frame, encoding a 264-amino-acid transmembrane glycoprotein with a predicted molecular mass of 29.4 kDa. The $swFc{\alpha}RI$ shares high amino acid sequence homology (>50%) with its counterparts from cattle, seal, and horse. Rosetting analysis confirmed that COS-7 cells transfected with an $swFc{\alpha}RI$ expression plasmid was able to combine with chicken erythrocytes sensitized with porcine IgA, but not IgG.

Anti-angiogenic, Anti-cell Adhesion Switch from Halophilic Enterobacteria

  • Lim, Jong Kwon;Seo, Hyo Jin;Kim, Eun Ok;Meydani, Mohsen;Kim, Jong Deog
    • Journal of Marine Bioscience and Biotechnology
    • /
    • v.1 no.3
    • /
    • pp.156-162
    • /
    • 2006
  • The halophilic enterobacteria, Enterobacteria cancerogenus, was isolated from the intestines of the fusiform fish (Trachurus japonicus) to yield a protein-like material termed PLM-f74. PLM-f74 was characterized by strong inhibition ratios to angiogenesis (82.8% at the concentration of $18.5{\mu}g/mL$) and elevated antioxidative capacities with low toxicity. The PLM-f74 is a glycoprotein comprised of saccharides and amino acids. PLM-f74 inhibited non-activated U937 monocytic cell adhesion to HUVECs activated with IL-$1{\beta}$ by 78.0%, and the adherence of U937 cells treated with the PLM-f74 and stimulated with IL-$1{\beta}$ to unstimulated HUVECs decreased by 102%. When both cell types were pretreated with PLM-f74, the adhesion of U937 cells to IL-$1{\beta}$ stimulated HUVECs was completely suppressed by 121% at a concentration of 18.5 ug/mL. PLM-f74 blocked signal pathways from VEGFR2, PI3K, ${\beta}$-catenin and VE-cadherin to NF-kB based on western bolt analysis. And also inhibited IL-1-stimulated HUVEC expression of the adhesion molecules, ICAM-1 by 40%, VCAM-1 by 60%, and E-selectin by 70% at the same concentration noted above. New anti-angiogenic and anti-cell adhesion materials showing elevated antioxidative capacities and non-toxicity may be expected from these results.

  • PDF

Cloning and Expression of a Thermostable ${\alpha}$-Galactosidase from the Thermophilic Fungus Talaromyces emersonii in the Methylotrophic Yeast Pichia pastoris

  • Simila, Janika;Gernig, Anita;Murray, Patrick;Fernandes, Sara;Tuohy, Maria G.
    • Journal of Microbiology and Biotechnology
    • /
    • v.20 no.12
    • /
    • pp.1653-1663
    • /
    • 2010
  • The first gene (${\alpha}$-gal1) encoding an extracellular ${\alpha}$-Dgalactosidase from the thermophilic fungus Talaromyces emersonii was cloned and characterized. The ${\alpha}$-gal1 gene consisted of an open reading frame of 1,792 base pairs interrupted by six introns that encoded a mature protein of 452 amino acids, including a 24 amino acid secretory signal sequence. The translated protein had highest identity with other fungal ${\alpha}$-galactosidases belonging to glycosyl hydrolase family 27. The ${\alpha}$-gal1 gene was overexpressed as a secretory protein with an N-terminal histidine tag in the methylotrophic yeast Pichia pastoris. Recombinant ${\alpha}$-Gal1 was secreted into the culture medium as a monomeric glycoprotein with a maximal yield of 10.75 mg/l and purified to homogeneity using Hisbinding nickel-agarose affinity chromatography. The purified enzyme was maximally active at $70^{\circ}C$, pH 4.5, and lost no activity over 10 days at $50^{\circ}C$. ${\alpha}$-Gal1 followed Michaelis-Menten kinetics ($V_{max}\;of\;240.3{\mu}M/min/mg,\;K_m\;of\;0.294 mM$) and was inhibited competitively by galactose ($K_m{^{obs}}$ of 0.57 mM, $K_i$ of 2.77 mM). The recombinant T. emersonii ${\alpha}$-galactosidase displayed broad substrate preference, being active on both oligo- and polymeric substrates, yet had strict specificity for the ${\alpha}$-galactosidic linkage. Owing to its substrate preference and noteworthy stability, ${\alpha}$-Gal1 is of particular interest for possible biotechnological applications involving the processing of plant materials.

HIV-1 Vaccine Development: Need For New Directions

  • Cho Michael W.
    • Proceedings of the Microbiological Society of Korea Conference
    • /
    • 2000.10a
    • /
    • pp.78-82
    • /
    • 2000
  • The AIDS epidemic continues unabated in many part of the world. After near two decades, no vaccine is available to combat the spread of this deadly disease. Much of the HIV -1 vaccine effort during the past decade has focused on the viral envelope glycoprotein, largely because it is the only protein that can elicit neutralizing antibodies (Nabs). Eliciting broadly cross-reactive Nabs has been a primary goal. The intrinsic genetic diversity of the viral envelope, however, has been one of the major impediments in vaccine development. We have recently completed a comprehensive study examining whether it is possible to elicit broadly acting Nabs by immunizing monkeys with mixtures of envelope proteins from multiple HIV -1 isolates. We compared the humoral immune responses elicited by vaccination with either single or multiple envelope proteins and evaluated the importance of humoral and non-humoral immune response in protection against a challenge virus with a homologous or heterologous envelope protein. Our results show that (1) Nab is the correlate of sterilizing immunity, (2) Nabs against primary HIV -1 isolates can be elicited by the live vector-prime/protein boost approach, and (3) polyvalent envelope vaccines elicit broader Nab response than monovalent vaccines. Nonetheless, our findings clearly indicate that the increased breadth of Nab response is by and large limited to strains included in the vaccine mixture and does not extend to heterologous non-vaccine strains. Our study strongly demonstrates how difficult it may be to elicit broadly reactive Nabs using envelope proteins and sadly predicts a similar fate for many of the vaccine candidates currently being evaluated in clinical trials. We have started to evaluate other vaccine candidates (e.g. genetically modified envelope proteins) that might elicit broadly reactive Nabs. We are also exploring other vaccine strategies to elicit potent cytotoxic T lymphocyte responses. Preliminary results from some of these experiments will be discussed.

  • PDF

Effect of Ethane 1,2-Dimethane Sulfonate(EDS) on the Expression of Pituitary Gonadotropin in Male Rats (수컷 흰쥐 뇌하수체의 생식소자극호르몬 발현에 미치는 Ethane 1,2-Dimethane Sulfonate(EDS)의 효과)

  • Son, Hyeok-Joon;Kim, Soo-Woong;Paick, Jae-Seung;Lee, Sung-Ho
    • Development and Reproduction
    • /
    • v.11 no.1
    • /
    • pp.49-54
    • /
    • 2007
  • Ethane 1,2-dimethane sulfonate(EDS), a toxin which specifically kills Leydig cells(LC), has been widely used to prepare the reversible testosterone(T) depletion rat model. In the present study, we monitored the gene expression profiles of pituitary gonadotropins, LH and FSH, up to 7 weeks after EDS injection. Adult male Sprague-Dawley rats($300{\sim}350\;g$ B.W.) were injected with a single dose of EDS(75 mg/kg i.p.) and sacrificed on weeks 0, 1, 2, 3, 4, 5, 6 and 7. Total RNAs were purified from each pituitary, and the message levels of common alpha subunit($C{\alpha}$) of pituitary glycoprotein hormones, LH beta subunit($LH{\beta}$), FSH beta subunit($FSH{\beta}$) and GnRH receptor(GnRH-R) were evaluated by semi-quantitative RT-PCRs. The message levels of $C{\alpha}$ increased sharply during weeks 1-4, then return to the control level on week 5. The mRNA levels of $LH{\beta}$ were elevated after week 2, reached the peak at week 4, then declined to the control level after week 5. The message levels of $FSH{\beta}$ were elevated after week 2, reached the peak at week 3, then declined to the nadir at week 5. Similarly, the mRNA levels of GnRH-R were elevated after week 2, reached the peak at week 3, then gradually declined to the control level after week 5. The present study indicated that EDS treatment could induce reversible alterations in the transcriptional activities of gonadotropin subunits and GnRH-R in the anterior pituitary from male rats. EDS injection model might be useful to understand the mechanism of hormonal regulation of hypothalamus- pituitary neuroendocrine axis in male rats.

  • PDF

STUDY OF ${\beta}$-GLUCURONIDASE FROM SULL SEMINAL PLASMA:PURIFICATION AND PROPERTIES (황소의 정액에서 베타-굴룩 유로니다아제의 정제 및 그 성질에 관한 연구)

  • Yang, Chul-Hak;Lee, Hee-Yong
    • Clinical and Experimental Reproductive Medicine
    • /
    • v.10 no.2
    • /
    • pp.1-11
    • /
    • 1983
  • ${\beta}$-Glucuronidase from bull seminal plasma was partially purified by $(NH_4)_2SO_4$fractionation, two successive DEAE-cellulose columns, isoelectric focusing (pH 4 to 6) and Gel filtration on Sephadex G-200. Only one form of ${\beta}$-glucuronidase was obtained by isoelectric focusing at pH 5.13. Highly purified ${\beta}$-glucuronidase had specific activity of 34 units/mg protein and showed one major and some minor contaminants by disc gelk electrophoresis. The enzyme showed maximum activity at pH 5.2 and at $48^{\circ}C$. The enzyme was completely inhibited by 1,4 saccharo-${\alpha}$-lactone (5 mM). Albumin and 0.15 M NaCl increased the ${\beta}$-glucuronidase activity. Km of ${\beta}$-glucuronidase using phenolphthalein mono-${\beta}$-glucuronic acid as substrate was 2.9 mM and Vmax was $0.8{\mu}$mole/min. The enzyme appeared to be a glycoprotein by its binding to concanvalin·A. Rabbit and human sperm-acrosomal extracts and seminal plasma showed high ${\beta}$-glucuronidase activity.

  • PDF