• 한국응용과학기술학회지
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• 제35권4호
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• pp.1369-1378
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• 2018

홍어 껍질 유래 콜라겐 펩타이드를 한외여과막을 이용하여 분자량의 크기를 1,000 Da 이하와 1,000 Da 이상으로 분리하고 그 효과를 비교하고자 하였다. 각각의 시료를 비만 유발 실험동물인 db/db mice에 체중당 200 mg의 콜라겐 펩타이드를 8주간 투여하였다. 본 연구의 결과는 콜라겐 펩타이드를 투여한 군에서 비만대조군에 비해 체중 증가량의 감소, 혈액 및 간조직의 활성산소 농도의 감소, 간조직의 산화적 스트레스가 완화된 것으로 나타났다. 또한 콜라겐 투여군에서 염증반응과 관련된 간조직의 핵전사인자($NF-{\kappa}B$) 및 효소(COX2, iNOS), 염증성 사이토카인(IL-6)발현이 비만대조군에 비해 유의적으로 감소하였다. 분자량의 크기에 따라 약간의 차이가 나타났지만, 전반적으로는 유의적이지 않았다. 따라서 홍어 콜라겐 펩타이드의 비만에 의해 유발된 염증반응이 억제되었는데, 이는 콜라겐의 산화적 스트레스 완화작용에 기인한 것으로 사료된다.

• Parasites, Hosts and Diseases
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• 제47권1호
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• pp.31-36
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• 2009

Cockroaches have been recognized as a major cause of asthma. Bla g 4 is one of the most important German cockroach allergens. The aim of this study is to investigate IgE reactivity to the recombinant Bla g 4 (rBla g 4) in the sera of allergic patients and identify linear IgE binding epitope. For protein expression, full-length Bla g 4 (EF202172) was divided into 5 overlapping peptide fragments (E1: aa 1-100, E2: aa 34-77, E3: aa 74-117, E4: aa 114-156, and E5: aa 153-182). The full-length and 5 peptide fragments of Bla g 4 was generated by PCR and over-expressed in E. coli BL21 (DE3). The IgE binding reactivities of the full-length and peptide fragments were measured by ELISA using 32 serum samples of cockroach allergy. The sera of 8 patients (25%) reacted with rBla g 4. Four sera (100%) showed IgE-binding reactivity to full-length and peptide fragment 4, and 2 sera (50%) reacted with peptide fragment 2. One (20%) serum reacted with peptide fragment 3. The results of ELISA using overlapping recombinant fragments indicated that the epitope region was located at amino acid sequences 34-73 and 78-113, and major IgE epitope of Bla g 4 was located at amino acid sequences 118-152 of C-terminal. B-cell epitope analysis of German cockroach allergen Bla g 4 could contribute to the strategic development of more specific and potentially efficacious immunotherapy.

• Asian Pacific Journal of Cancer Prevention
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• 제13권7호
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• pp.3053-3059
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• 2012

Human epidermal growth factor receptor 2 (HER2) is a member of the epidermal growth factor receptor family of receptor tyrosine kinases that plays important roles in all processes of cell development. Their overexpression is related to many cancers, including examples in the breast, ovaries and stomach. Anticancer therapies targeting the HER2 receptor have shown promise, and monoclonal antibodies against subdomains II and IV of the HER2 extra-cellular domain (ECD), Pertuzumab and Herceptin, are currently used in treatments for some types of breast cancers. Since anti HER2 antibodies targeting distinct epitopes have different biological effects on cancer cells; in this research linear and conformational B cell epitopes of HER2 ECD, subdomain III, were identified by bioinformatics analyses using a combination of linear B cell epitope prediction web servers such as ABCpred, BCPREDs, Bepired, Bcepred and Elliprro. Then, Discotope, CBtope and SUPERFICIAL software tools were employed for conformational B cell epitope prediction. In contrast to previously reported epitopes of HER2 ECD we predicted conformational B cell epitopes $P1_C$: 378-393 (PESFDGDPASNTAPLQ) and $P2_C$: 500-510 (PEDECVGEGLA) by the integrated strategy and P4: PESFDGD-X-TAPLQ; P5: PESFDGDP X TAPLQ; P6: ESFDGDP X NTAPLQP; P7: PESFDGDP-X-NTAPLQ; P8: ESFDG-XX-TAPLQPEQL and P9: ESFDGDP-X-NTAPLQP by SUPERFICIAL software. These epitopes could be further used as peptide antigens to actively immune mice for development of new monoclonal antibodies and peptide cancer vaccines that target different epitopes or structural domains of HER2 ECD.

• Asian-Australasian Journal of Animal Sciences
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• 제16권10호
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• pp.1460-1468
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• 2003

An experiment was conducted to quantify the flow of soluble non-ammonia nitrogen (SNAN) in the liquid phase of ruminal (RD) and omasal digesta (OD), and to investigate diurnal pattern in SNAN flow in OD. Five ruminally cannulated Finnish-Ayrshire dairy cows in a $5{\times}5$ Latin square design consumed a basal diet of grass silage and barley grain, and that supplemented with four protein feeds (kg/d DM basis) as follows: skimmed milk powder (2.1), wet distiller' solubles (3.0), untreated rapeseed meal (2.1) and treated rapeseed meal (2.1). Ruminal digesta was sampled using a vacuum pump, whereas OD was collected using an omasal sampling system at 1.0 h interval during a 12 h feeding cycle. Both RD and OD were acidified, centrifuged to remove microbes and precipitated with trichloroacetic acid followed by centrifugation. The SNAN fractions (free amino acid (AA), peptide and soluble protein) in RD and OD were assessed using ninhydrin assay. Free AA, peptide and soluble protein averaged 60.0, 89.4 and 2.1 g/d, respectively, for RD, and 81.8, 121.5 and 2.5 g/d, respectively, for OD. Although free AA flow was relatively high, mean peptide flow was quantitatively the most important fraction of SNAN, indicating that degradation of peptide to AA rather than hydrolysis of soluble protein to peptide or deamination may be the most limiting step in rumen proteolysis. Diurnal pattern in flow of peptide including free AA in OD during a 12 h feeding cycle peaked 1 h post-feeding, decreased by 3 h post-feeding and was relatively constant thereafter. Protein supplementation showed higher flow of peptide including free AA immediately after feeding compared with no supplemented diet. There were no differences among protein supplements in diurnal pattern in flow of peptide including free AA in OD.

• 한국융합학회논문지
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• 제13권1호
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• pp.101-107
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• 2022

Tertomotide는 항암제로 개발된 펩타이드 백신이다. 그러나 동물실험과 임상시험에서 염증성 증상이 완화되는 현상이 발견된바 있다. 이에 tertomotide가 항염물질로 작용하는지 확인하기 위하여 직접적인 항염활성과 그 작용기전을 조사하였다. 이를 위해 LPS 또는 PMA에 의해 활성화된 monocyte에 tertomotide를 처리한 후 염증성 cytokine 생산과 관련된 신호전달과정을 관찰하였다. Monocyte에서 tertomotide는 TNF-α, IL-1β, IL-8 등 염증성 싸이토카인의 생산을 감소시켰고 NF-κB 신호를 감쇄시켰으며 또한 TNF-α에 의한 ERK1/2와 P38 MAPK의 활성화를 저해하였다. 이 결과는 tertomotide 처치에 따른 염증성 질환 완화가 NF-κB/STAT3의 신호의 감쇄와 항염활성에 의한 것이라고 설명할 수 있고 이를 활용하여 신규 항염 약물의 도출이 가능할 것으로 판단된다. 이는 면역학적 활성을 목표로 계산화학적으로 설계된 물질의 생물학적 성질을 활용하여 새로운 약물을 도출하는 융합연구의 예시가 될 것이다.

• 혜화의학회지
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• 제15권1호
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• pp.141-160
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• 2006

The obtained results are summarized as follows 1. New findings are reporting year by year as for the study related to Anti-inflammatory mechanism of Bee Venom therapy. 2. The Anti-inflammatory effect of Bee Venom therapy is achieved through counterirritation, stimulations to adrenal cortex, immuno-regulation, antioxidation, removal of free radicals, modulation of AGP gene induction. 3. The chief components of Bee Venom related to Anti-inflammatory effect are Melittin, MCD peptide, Apamin, Adolapin etc. 4. Melittin binds to secretory phospholipase A2 and inhibits its enzymatic activity. 5. Melittin blocks neutophil O2-production. 6. MCD peptide(Peptide 401) stimulates the mast cell secrets histamine, Anti-inflammatory effect caused by this is 'conterirritation'. 7. Melittin & Apamin have an anti-inflammatory effect by inducing cortisone secretion. 8. MCD peptide & Apamin increase immunologic fuction by stimulating hypophysis & adrenal cortex and have an anti-inflammatory effect by inhibiting synthesis of prostaglandin from arachidonic acid. 9. Adolapin have an anti-inflammatory effect by inhibiting COX. 10. Bee Venom have an anti-inflammatory effect by suppressing AGP($\alpha$-acid glycoprotein). 11. Bee Venom have an anti-inflammatory effect by inhibiting NO, iNOS, PLA2, COX-2, TNF-$\alpha$, IL-1, NF-${\kappa}B$, MAP kinase.

• 한국식품영양과학회지
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• 제29권4호
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• pp.719-725
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• 2000

본 연구는 70여종의 국내산 해조류중 가장 높은 ACE 저해 활성을 보였던 김(Porphyra yezoensis, 서천)의 산가수분해물로부터 ACE 활성 저해 펩타이 드를 분리하여 그 특성을 조사하였다. ACE 저해물질의 분획은 균일하게 파쇄한 김을 2.5 N HCl로 산 가수분해한 후 중화하여 한외여과로 분자크기 3 kDa 이하의 물질로 분리하였다. 분자크기 3 kDa이하의 물질에 대하여 column chromatography(Amberlite XAD 8, DEAE-Toyopearl, Sephadex LH-20)와 reverse phase HPLC(C18)를 순차적으로 수행하여 ACE 저해제인 PY3--II-b-h5물질을 분리하였다. PY30-II-b-h5는 분자크기는 약 580 dalton으로 glycine(24.5%), arginine(56.8%), proline(18.8%)의 아미노산 조성을 갖는 저분자 펩타이드였으며, ACE의 저해양상은 경쟁적 저해작용을 하였고, IC50 값은 10.6$\mu\textrm{g}$/mL 이었다.

• 대한수의학회지
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• 제25권1호
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• pp.7-17
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• 1985

Many investigators have been pursuing various attempts so far to produce hepatitis B surface antigen(HBsAg) vaccines using the techniques such as isolation from plasma of chronic HBsAg carrier, recombinant DNA technique or preparation of synthetic peptides specific for immunogenic determinants. Hepatitis B virus can not grow on any cell lines by the tissue culture technique at the present time. The plasma of chronic HBsAg carrier is expensive and its source is limited. The HBsAg from the recombinant DNA technique gave still very low yield. Another approach, therefore, has been initiated to develop a synthetic hepatitis B virus vaccine. The possible use of several distinct synthetic vaccines in prophylaxis can be facilitated by availability of full synthetic immunogens. Peptides synthesized for potential application as antiviral vaccines have been mostly tested in the form of conjugates with carrier proteins, although the free synthetic peptide can be immunogenic. To understand basic knowledges on the antigenicity and immunogenicity of a synthetic peptide specific for major immunogenic determinant of HBsAg, a nonapeptide, $H_2N^{139}Cys-Thr-Lys-Pro-Thr-Asp-Gly-^{146}Asn-Aba$ COOH, which corresponds to HBsAg amino acid residues 139 to 147, was synthesized by the Merrifield's solid-phase method with a slight modification. The antigenicity and immunogenicity of this specific synthetic peptide were examined comparing with purified plasma-derived natural HBsAg. The results obtained are as follows; 1. The peptide synthesized showed the identical amino acid composition to the theoretical value. The degree of purification and molecular weight were acertained by methods of high performance liquid chromatography and mass spectrometry. 2. Using m-maleimidobenzoyl-N-hydroxysuccinimide ester as a conjugating agent, the synthetic peptide was conjugated to rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin. Their conjugation yields were 8.3, 9.5, 15.8, 13.5, and 11.2%, respectively. 3. The natural HBsAg was purified from plasma of chronic HBsAg carrier. By the electron microscopic observation of the purified natural HBsAg preparation, no Dane particles were observed and the preparation showed negative DNA polymerase activity. 4. Antigenicity of the synthetic peptide and the plasma-derived natural HBsAg was determined by competition radioimmunoassay using $^{125}I$-natural HBsAg. Their 50% inhibitions appeared as $90{\mu}g/ml$ and $0.12{\mu}g/ml$ for the synthetic peptide and the natural HBsAg, respectively. This indicates that the former was about 750-fold less antigenic than the latter. 5. Immunogenicity of the synthetic peptide was determined by administering the peptide-carrier conjugates into rabbits with and without Freund's complete adjuvant. Regardless the carrier proteins and adjuvant, positive immune responses to the synthetic peptide were observed. The higher antibody titers, however, were shown in the groups administered with Freund's complete adjuvant. 6. Immunizing dose 50% in mice of the various peptide-carrier conjugates was 5.47, 6.00, 65.16, 31.25 and $13.03{\mu}g/dose$ for rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin, respectively, while the natural HBsAg showed $0.65{\mu}g/dose$. 7. It was postulated that homologous proteins prefer to heterologous ones as the carriers.

• International Journal of Industrial Entomology and Biomaterials
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• 제17권1호
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• pp.131-135
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• 2008

A cDNA encoding a defensin-like peptide (Protaetiamycine) from the larvae of a beetle, Protaetia brevitarsis was cloned. The DNAs encoded the deduced propeptide of 79 amino acid residues with the predicted molecular weight of 8.4 kDa and PI of 8.24. Overall amino acid sequence of this protein has 39% similarity to that of Rhodnius prolixus defensin, 43% similarity to that of Acalolepta luxuriosa defensin, and 72% similarity to that of Oryctes rhinoceros defensin, suggesting that this gene is an insect defensin. In an attempt to apply the anti-bacterial peptide to the development of therapeutic agents, a 12-mer peptide amidated at its C-terminus, ACAAHCLAIGRG-$NH_2$ (Ala55-Lys66-$NH_2$, 12Pbn) was synthesized. This peptide showed some antifungal activity against Candida albicans. To increase antifungal activity, six 9-mer peptides were synthesized by modifying amino acid sequences of 12Pbn fragment. Among these peptides, 9Pbm3-9Pbm6 exhibited strong activity compared with Cecropin B and mellitin.

• Journal of Microbiology and Biotechnology
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• 제34권6호
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• pp.1222-1228
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• 2024

Protein-specific antibodies are essential for various aspects of protein research, including detection, purification, and characterization. When specific antibodies are unavailable, protein tagging is a useful alternative. Small epitope tags, typically less than 10 amino acids, are widely used in protein research due to the simple modification through PCR and reduced impact on the target protein's function compared to larger tags. The 2B8 epitope tag (RDPLPFFPP), reported by us in a previous study, has high specificity and sensitivity to the corresponding antibody. However, when attached to the C-terminus of the target protein in immunoprecipitation experiments, we observed a decrease in detection signal with reduced immunity and low protein recovery. This phenomenon was not unique to 2B8 and was also observed with the commercially available Myc tag. Our study revealed that C-terminal tagging of small epitope tags requires the addition of more than one extra amino acid to enhance (restore) antibody immunities. Moreover, among the amino acids we tested, serine was the best for the 2B8 tag. Our findings demonstrated that the interaction between a small epitope and a corresponding paratope of an antibody requires an extra amino acid at the C-terminus of the epitope. This result is important for researchers planning studies on target proteins using small epitope tags.