• Journal of Life Science
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• v.30 no.9
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• pp.804-812
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• 2020

The giant mealworm beetle, Zophobas atratus (Coleoptera: Tenebrionidae) has been used as a protein source for small pets and mammals. Recently, it was temporarily registered in the list of the Food Code. We previously performed an in silico analysis of the Zophobas atratus transcriptome to identify putative antimicrobial peptides and identified several antimicrobial peptide candidates. Among them, we assessed the antimicrobial and anti-inflammatory activities of zophobacin 1 that was selected bio-informatically based on its physicochemical properties against microorganisms and mouse macrophage Raw264.7 cells. Zophobacin 1 showed antimicrobial activities against microorganisms without inducing hemolysis and decreased the nitric oxide production of the lipopolysaccharide-induced Raw264.7 cells. Moreover, ELISA and Western blot analysis revealed that zophobacin 1 reduced expression levels of pro-inflammatory enzymes such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). We also investigated expression of pro-inflammatory cytokines (interleukin-6 and interleukin-1β) production through quantitative real time-PCR and ELISA. Zophobacin 1 markedly reduced the expression level of cytokines through the regulation of mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling. We confirmed that zophobacin 1 bound to bacterial cell membranes via a specific interaction with lipopolysaccharides. These data suggest that zophobacin 1 could be promising molecules for development as antimicrobial and anti-inflammatory therapeutic agents.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.81-81
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• 2017

Nanotechnology is of great importance to molecular biology and medicine because life processes are maintained by the action of a series of molecular nanomachines in the cell machinery. Recent advances in nanoscale materials that possess emergent physical properties and molecular organization hold great promise to impact human health in the diagnostic and therapeutic arenas. In order to be effective, nanomaterials need to navigate the host biology and traffic to relevant biological structures, such as diseased or pathogenic cells. Moreover, nanoparticles intended for human administration must be designed to interact with, and ideally leverage, a living host environment. Inspired by nature, we use peptides to transfer biological trafficking properties to synthetic nanoparticles to achieve targeted delivery of payloads. In this talk, development of nanoscale materials will be presented with a particular focus on applications to three outstanding health problems: bacterial infection, cancer detection, and traumatic brain injury. A biodegradable nanoparticle carrying a peptide toxin trafficked to the bacterial surface has antimicrobial activity in a pneumonia model. Trafficking of a tumor-homing nanoprobes sensitively detects cancer via a high-contrast time-gated imaging system. A neuron-targeted nanoparticle carrying siRNA traffics to neuronal populations and silences genes in a model of traumatic brain injury. Unique combinations of material properties that can be achieved with nanomaterials provide new opportunities in translational nanomedicine. This framework for constructing nanomaterials that leverage bio-inspired molecules to traffic diagnostic and therapeutic payloads can contribute on better understanding of living systems to solve problems in human health.

• Animal cells and systems
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• v.16 no.6
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• pp.455-461
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• 2012

Amongst the various antimicrobial peptides, lysozyme plays a central role in initiating and maintaining the antibacterial defense response of insect. Here we propose the biosynthesis and refolding of recombinant lysozyme in Escherichia coli expressed in inclusion body form. The Agrius lysozyme gene was amplified using gene specific primers and then ligated into the pGEX-4T-1 vector, which contained the glutathione S-transferase (GST) gene as a fusion partner. A recombinant lysozyme was expressed in E. coli Rosetta cells using a pGEX-4T-1 expression vector, and the fusion protein was induced by ioporpyl-${\beta}$-D-thiogalactopyranoside (IPTG). The recombinant protein produced as an inclusion body was resolubilized in solubilization buffer, and the resultant solution was dialyzed in refolding buffer. After thrombin cleavage, the recombinant lysozyme was purified by ion exchange chromatography and reverse phase chromatography. The recombinant lysozyme was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis and immunoreactivity against the anti-Agrius lysozyme was observed by western blot analysis of this protein. The recombinant lysozyme displayed antibacterial activity against Bacillus megaterium and Micrococcus luteus, which was confirmed by the inhibition zone assay.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1116-1121
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• 1997

Effects of gamma irradiation onf the activity and the properties(amino acid compositions, in vitro digestibility and SDS-PAGE pattern) of proteolytic enzymes were investigated. The proteolytic activity of soluble human serine protease, enzyme in kiwi and pineapple decreased 10% and 30~65% by 5 kGy and 30 kGy, respectively. In dried pancreatin and lysozyme, the proteolytic and antimicrobial activities decreased 6~14% and 10~20% by 5kGy and 40kGy, respectively. The analysis of above 10kGy-irradiated soluble human serine protease by SDS-PAGE revealed radiolysis of the enzyme into protein or peptides of lower molecular weights. The irradiation of skim milk, hammastein casein, and lysozyme up to 40kGy had no deleterious effect on either the in vitro digestibility or amino acid compositions.

• International Journal of Advanced Culture Technology
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• v.7 no.3
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• pp.10-24
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• 2019

This study aimed to investigate the effects and epidermis penetration system with polymer micelle of Red Pinus densiflora extract. In the antioxidant test, the total concentration of polyphenol compounds was determined to be $137.5163{\pm}7.70mg/g$ in ethanol extract, $133.956{\pm}1.57mg/g$ in hydrothermal extract. The DPPH radical scavenging effects were $95.29{\pm}0.15%$ in ethanol extract at 1,000 mg/L. Elastase inhibition rates were $100.00{\pm}2.85%$ in ethanol extract at 2,000 mg/L. The antimicrobial effect of the ethanol extraction was higher than that of hydrothermal extractions. In the epidermal permeability experiment, it was confirmed that the permeation of the polymer micelle containing the Red Pinus densiflora's ethanol extract and cell penetrating peptides was remarkable. Here, we confirmed that ethanol extract of Red Pinus densiflora displayed excellent the effects in antioxidant test and epidermis penetration system with polymer micelle. As a result, Red Pinus densiflora extract has potential to be used as a safe and natural cosmetic material in the future.

• IMMUNE NETWORK
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• v.21 no.3
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• pp.19.1-19.18
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• 2021

Clinical and molecular phenotypes of asthma are complex. The main phenotypes of adult asthma are characterized by eosinophil and/or neutrophil cell dominant airway inflammation that represent distinct clinical features. Upper and lower airways constitute a unique system and their interaction shows functional complementarity. Although human upper airway contains various indigenous commensals and opportunistic pathogenic microbiome, imbalance of this interactions lead to pathogen overgrowth and increased inflammation and airway remodeling. Competition for epithelial cell attachment, different susceptibilities to host defense molecules and antimicrobial peptides, and the production of proinflammatory cytokine and pattern recognition receptors possibly determine the pattern of this inflammation. Exposure to environmental factors, including infection, air pollution, smoking is commonly associated with asthma comorbidity, severity, exacerbation and resistance to anti-microbial and steroid treatment, and these effects may also be modulated by host and microbial genetics. Administration of probiotic, antibiotic and corticosteroid treatment for asthma may modify the composition of resident microbiota and clinical features. This review summarizes the effect of some environmental factors on the upper respiratory microbiome, the interaction between host-microbiome, and potential impact of asthma treatment on the composition of the upper airway microbiome.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.721-726
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• 2012

Lactic acid bacteria (LAB) are able to secrete antimicrobial peptides called bacteriocins, which inhibit other bacteria such as pathogenic microorganisms. Therefore, bacteriocin-producing starters can be used as natural biopreservatives for various foods. The objective of this study was to screen and characterize bacteriocin-producing LAB from Kimchi and to investigate their applicability as a starter in Kimchi fermentation. To screen bacteriocin-producing LAB, gram-positive and gram-negative bacteria were used as indicators. To measure the antimicrobial activities of isolates, agar well diffusion assay method was used. According to the results, bacteriocin produced by $Lb.$ $sakei$ B16 showed antimicrobial activity against $Listeria$ $monocytogenes$ ATCC 19115, $Escherichia$ $coli$ KCTC 1467, and$Lactobacillus$ $plantarum$ KTCT 3104. Furthermore, bacteriocin was very stable after treatment with high temperature and high and low pH, but its effects were inhibited by treatment with proteolytic enzymes such as trypsin, proteinase K, and ${\alpha}$-chymotrypsin, revealing their bacteriocin-like protein- based structure. These results suggest that $Lb.$ $sakei$ B16 and its bacteriocin are good candidates as a functional probiotic and natural biopreservative, respectively, in fermented foods.

• Journal of Life Science
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• v.32 no.12
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• pp.956-961
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• 2022

Plant Chloroplast have several advantages as an expression platform of biopharmaceuticals over conventional expression platforms such as mammalian cells, yeast and bacteria. First, plants do not serve as a host for mammalian infectious virus and have endotoxin like bacteria which can cause anaphylactic shock. In addition, high copy number of chloroplast genome allows for chloroplast transformants to reach the high level of expression of heterologous genes. Moreover, the integration of transgenes into specific region of chloroplast genomes makes chloroplast transformants unaffected by positional effect which can be frequently observed from nuclear transformants, resulting in loss of transgene expressions. Antimicrobial peptides (AMPs) are a kind of innate immunity which is found from bacteria to humans. Unlike conventional antibiotics, very less dosage of AMPs can have catastrophic effect on bacterial survival. Further, the repeated use of AMPs does not trigger the development of bacterial resistance. Moricin, one of the AMPs, was isolated from Bombyx mori, a silkworm moth. The C-terminal of moricin consists largely of basic amino acids, and the N-terminal has an α-helix structure. Moricin was chosen and expressed in a SUMO/SUMOase without leaving any unwanted amino acids which could potentially affect the anti-bacterial activity of the moricin. The transformation vector used in this study has already been created in this lab for the expression in both prokaryotic systems such as E. coli and chloroplast. The expressed moricin was purified using Ni columns and SUMOase, and the antibacterial activity of the purified moricin was confirmed using an agar diffusion assay.

• Journal of Life Science
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• v.30 no.10
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• pp.886-895
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• 2020

The development of novel peptide antibiotics with potent antimicrobial activity and anti-inflammatory activity is urgently needed. In a previous work, we performed an in-silico analysis of the Papilio xuthus transcriptome to identify putative antimicrobial peptides and identified several candidates. In this study, we investigated the antibacterial and anti-inflammatory activities of papiliocin 3, which was selected bioinformatically based on its physicochemical properties against bacteria and mouse macrophage Raw264.7 cells. Papiliocin 3 showed antibacterial activities against E. coli and S. aureus without inducing hemolysis and decreased the nitric oxide production of the lipopolysaccharide-induced Raw264.7 cells. Moreover, ELISA and Western blot analysis revealed that papiliocin 3 reduced the expression levels of pro-inflammatory enzymes, such as inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and prostaglandin E₂ (PGE₂). In addition, we examined whether papiliocin 3 could inhibit the expression of pro-inflammatory cytokines (interleukin-6 and interleukin-1β) in LPS-induced Raw264.7 cells. We found that papiliocin 3 markedly reduced the expression level of cytokines through the regulation of mitogen-activated protein kinases (MAPK) and nuclear factor kappa B (NF-κB) signaling. We also confirmed that papiliocin 3 binds to bacterial cell membranes via a specific interaction with lipopolysaccharides. Collectively, these findings suggest that papiliocin 3 could be a promising molecule for development as a novel peptide antibiotic.

• Journal of the Korean Applied Science and Technology
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• v.33 no.2
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• pp.293-303
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• 2016

Protein hydrolysate that shows physiological function such as antioxidant, suppression of hypertension, immunodulatory, alleviation of pain, and antimicrobial activity has been known as playing important role like hormone. This study was performed to optimize the hydrolysis of the wing's meat of Yosan-Ogae by a commercial protease. The ranges of processes were the reaction temperature of 40 to $60^{\circ}C$, pH 6 to 8, and enzyme concentration 1 to 3%(w/v). As a result, the optimization of process was determined at temperature of $48-50^{\circ}C$, pH of 7.0-7.2, and enzyme concentration of 3%(w/v), and degree of hydrolysis was 68 to 69% at above conditions. The molecular weight of hydrolysate was distributed to 500-1,200 Da and showed typical peptides. The amino acids of peptides showing presumably antioxidant activity such as histidine, proline, methionine, cystein, tyrosine, tryptophan, phenylalanine comprised about 43.07%. The glutamic acid was 13.6%. Therefore, we expect that those products are useful as functional food ingredients.