• Journal of Life Science
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• v.15 no.4 s.71
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• pp.528-535
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• 2005

The non-enzymatic anti-oxidants and lunasin peptide from the extracts of the pepper were examined in order to utilize the discovery in natural products as cancer chemopreventive agents. The DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical scavenging activity on the fruit parts of the pepper was higher than that of the seed, but the difference was low. The Inhibition activity of xanthine/ xanthine oxidase in extracts of the seed was higher than that of the fruit and that of the seed on 20 days after flowering was the highest at the growing period. These were identified as fatty acids and phenolic compounds such as 1-eicosanol, palmitic acid, linoleic acid, linolenic acid and benzonitrile. The contents of fatty acids and phenolic compounds increased according to the time passing at the growing period. Peroxidase (POD) activity of the fruit at middle stage was high than that of other growing stages and that of the seed was the highest at later growing period. Though superoxide dismutase (SOD) activities in fruit were hish by passage of Slowing stage, the activity in seed was low. Lunasin was searched from seeds of the peppers by coomassie blue staining and western blot among them and we just found lunasin peptide from extracted protein of the pepper by western blot. In addition, we observed the contents of lunasin after flowering and confirmed to appear the lunasin at 35 days after flowering. We confirmed that lunasin is complex protein of maturing seeds. 100nM lunasin peptide in pepper showed inhibition effect on colony formation in $2\~12$ cells.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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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.

• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1596-1596
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• 2012

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.469-474
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• 2004

The objective of the current study was to determine the effects of arabinoxylane and polysaccharide peptide (PSP) on the immune cell functions. Both arabinoxylane and PSP increased plaque forming cell (10-15%) and rosette forming cell (10-30%) formation. Stimulation of macrophage with PSP (18%) and arabinoxylane (22%) resulted in increased phagocytic effects. Both arabinoxylane and PSP induced the tumor suppressive effect in mice injected sarcoma-180 cell intracutaneously. When the mice injected intraperitoneal cavity with sarcoma 180 cells, survival ratio was increased in the mice fed on arabinoxylane and PSP. The ratio of PCA was slightly decreased in the mice fed on PSP, especially fed on arabinoxylane than in the control mice. The concentrations of blood histamine were slightly decreased in the mice fed on arabinoxylane and PSP. These results suggest that the capacity of arabinoxylane and PSP seems to act as a potent immunomodulator causing augmentation of immune cell activity, and with the absence of notable side-effects, arabinoxylane and PSP could be used as a biological response modifier having possible therapeutic effects against immunological disorders.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.293-297
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• 2016

TRAIL, tumor necrosis factor (TNF)-related apoptosis-inducing ligand belongs to one of important cytokine superfamilIES, tumor necrosis factor ($TNF{\alpha}$). TRAIL-2 receptor agonists activate several cell signaling pathways in cells in different manners and could lead to apoptosis or necrosis. Agonistic egg yolk antibodies like IgY which have been developed in a selective manner could activate TRAIL death receptors such as TRAIL-2 (DR5) and thus apoptosis signaling. We here investigated induction of apoptosis in human breast cancer cells (MCF7 cell line) by an IgY produced against an 21 aminoacid epitope of the human TRAIL-2 receptor. As the first step a small peptide of 21 aminoacids choosen from the extracellular domain of DR5 protein was produced with a peptide synthesizer. After control assays and confirmation of the correct amino acid sequence, it was injected to hens immunized to achieve high affinity IgYs. At the next step, the produced IgYs were extracted and examined for specificity against DR5 protein by ELISA assay. Subsequently, the anticancer effect of such IgYs was determined by MTT assay in the MCF7 human breast cancer cell line. The produced peptides successfully immunized hens and the produced antibodies which accumulated in egg yolk specifically recognized the DR5 protein. IgYs exerted significant toxicity and killed MCF7 cells as shown by MTT assay.

• Microbiology and Biotechnology Letters
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• v.49 no.1
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• pp.75-87
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• 2021

Type I Interferons (IFNα) are known for their role as biological anticancer agents owing to their cell-apoptosis inducing properties. Development of an appropriate, cost-effective host expression system is crucial for meeting the increasing demand for proteins. Therefore, this study aims to develop codon-optimized IFNα-2b in L. lactis NZ3900. These cells express extracellular protein using the NICE system and Usp₄₅ signal peptide. To validate the mature form of the expressed protein, the recombinant IFNα-2b was screened in a human colorectal cancer cell line using the cytotoxicity assay. The IFNα-2b was successfully cloned into the pNZ8148 vector, thereby generating recombinant L. lactis pNZ8148-SP_Usp45-IFNα-2b. The computational analysis of codon-optimized IFNα-2b revealed no mutation and amino acid changes; additionally, the codon-optimized IFNα-2b showed 100% similarity with native human IFNα-2b, in the BLAST analysis. The partial size exclusion chromatography (SEC) of extracellular protein yielded a 19 kDa protein, which was further confirmed by its positive binding to anti-IFNα-2b in the western blot analysis. The crude protein and SEC-purified partial fraction showed IC₅₀ values of 33.22 ㎍/ml and 127.2 ㎍/ml, respectively, which indicated better activity than the metabolites of L. lactis NZ3900 (231.8 ㎍/ml). These values were also comparable with those of the regular anticancer drug tamoxifen (105.5 ㎍/ml). These results demonstrated L. lactis as a promising host system that functions by utilizing the pNZ8148 NICE system. Meanwhile, codon-optimized usage of the inserted gene increased the optimal protein expression levels, which could be beneficial for its large-scale production. Taken together, the recombinant L. lactis IFNα-2b is a potential alternative treatment for colorectal cancer. Furthermore, its activity was analyzed in the WiDr cell line, to assess its colorectal anticancer activities in vivo.

• Journal of Dairy Science and Biotechnology
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• v.16 no.2
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• pp.98-105
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• 1998

Various peptides derived from food are among the most potent physiologically active agents known, and include anticancer peptides, angiotensin converting enzyme(ACE) inhibitor exhibiting antihypertension action, opioid peptides, antithrombotic peptides, hypocholesterolemic peptides, immunomodulators, calcium absorption enhancers, and other peptides. Hydrophobic peptides extracted from a Cheddar-type cheese slurry were fractionated by gel chromatography and repeated HPLC. A peptide fraction from HPLC showed high cytotoxicity on the tumor cell lines such as a human colon carcinoma, and comprised of Tyr, Ser, Leu, Gly, and others. Hypocholesterolemic peptides were isolated from peptic hydrolyzates of casein and soy proteins. Macropeptides of 1,000${\sim}$5,000 dalton were effective on reducing the cholesterol level of mouse serum. Peptides showing high Krigbaum hydrophobicity and ANS surface hydrophobicity resulted in high hypocholesterolemic effect and fecal steroid concentrations. Caseinomacropeptides(CMP) were isolated from whey powder and treated with soluble and immobilized trypsin to obtain antithrombotic peptides. One fraction from the CMP hydrolyzed with immobilized trypsin for 24h exhibited high antithrombotic activity with 52.5% inhibition of platelet aggregation. These result suggested that peptides from various milk products could be utilized as a good bioactive agents for developing health functional foods.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.637-647
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• 2016

Proliferating cell nuclear antigen (PCNA) is a critical eukaryotic replication accessory factor that supports DNA binding in DNA processing, such as DNA replication, repair, and recombination. PCNA consists of three toroidal-shaped monomers that encircle double-stranded DNA. The diverse functions of PCNA may be regulated by its interactions with partner proteins. Many of the PCNA partner proteins generally have a conserved PCNA-interacting peptide (PIP) motif, located at the N- or C- terminal region. The PIP motif forms a 3₁₀ helix that enters into the hydrophobic groove produced by an interdomain-connecting loop, a central loop, and a C-terminal tail in the PCNA. Post-translational modification of PCNA also plays a critical role in regulation of its function and binding partner proteins. Structural and biochemical studies of PCNA-protein will be useful in designing therapeutic agents, as well as estimating the outcome of anticancer drug development. This review summarizes the characterization of eukaryotic PCNA in relation to the protein structures, functions, and modifications, and interaction with proteins.

• 한국유가공학회:학술대회논문집
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• 1998.05a
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• pp.22-29
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• 1998

Various peptides derived from food are among the most potent physiologically active agents known, and include anticancer peptides, angiotensin converting enzyme(ACE) inhibitor exhibiting antihypertension action, opioid peptides, antithrombotic peptides, hypocholesterolemic peptides, immunomodulators, calcium absorption enhancers, and other peptides. Hydrophobic peptides extracted from a Cheddar-type cheese slurry were fractionated by gel chromatography and repeated HPLC. A peptide fraction from HPLC showed high cytotoxicity on the tumor cell lines such as a human colon carcinoma, and comprised of Tyr, Ser, Leu, Gly, and others. Hypocholesterolemic peptides were isolated from peptic hydrolyzates of casein and soy proteins. Macropeptides of 1,000${\sim}$5,000 dalton were effective on reducing the cholesterol level of mouse serum. Peptides showing high Krigbaum hydrophobicity and ANS surface hydrophobicity resulted in high hypocholesterolemic effect and fecal steroid concentrations. Caseinomacropeptides (CMP) were isolated from whey powder and treated with soluble and immobilized trypsin to obtain antithrombotic peptides. One fraction from the CMP hydrolyzed with immobilized trypsin for 24h exhibited high antithrombotic activity with 52.5% inhibition of platelet aggregation. These results suggested that peptides from various milk products could be utilized as a good bioactive agents for developing health functional foods.

• Microbiology and Biotechnology Letters
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• v.49 no.4
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• pp.493-500
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• 2021

Argyrins are a group of anticancer and antibacterial octapeptide bioactive substances isolated from myxobacteria. In this study, we showed that the myxobacterium Archangium gephyra MEHO_001, isolated in Korea, produces argyrins A and B. MEHO_001 cells tend to aggregate when cultured in liquid media. Hence, a dispersion mutant, MEHO_002, was isolated from MEHO_001. The MEHO_002 strain produced approximately 3.5 times more argyrins than that produced by the wild-type strain MEHO_001. We determined the whole-genome sequence of A. gephyra MEHO_002 and identified a putative argyrin biosynthetic gene cluster comprising five genes, arg1-arg5, encoding non-ribosomal peptide synthases and tailoring enzymes. Inactivation of arg2 by plasmid insertion disrupted argyrin production. The amino acid sequences of the proteins encoded by arg2-arg5 of A. gephyra MEHO_002 were 90-98% similar to those encoded by the argyrin biosynthetic genes of Cystobacter sp. SBCb004, an argyrin-producing myxobacterium with identical domain organization.