• YAKHAK HOEJI
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• v.57 no.6
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• pp.400-405
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• 2013

In this study, we measured the complex efficiency of a physiologically active antibody, a chelator and radiosiotopes using the ESI-TOF/Ms system for develop good radiopharmaceuticals. For a precise measurement, TLC is a low accuracy method. Loading of same amount of sample is difficult for each test, and work to quantify accurately the results obtained through TLC cannot be afforded compared to the use of other analytical instruments. The method of analysis using a mass spectrometer is capable of a mass analysis of proteins for quantitative analysis. The conjugates of the chelator (CHX-A- DTPA) and the antibody (IgG) were separated through MWCO, and were analyzed using ESI-TOF and MALDI-TOF mass spectrometry. The analysis using MALDI-TOF is roughly divided into measurements on mass spectrometry. When conjugating a small molecular weight of CHX-A-DTPA and a large molecular weight of IgG, distinguishing the peak of the conjugate and the peak of IgG was difficult. However, an ESI-TOF mass spectrometer system is capable of an analysis of mass by decentralizing the IgG. It is utilized as a technique for measuring the metabolic processes during conjugation and the stability evaluation of radiopharmaceuticals. When establishing this technique, the accuracy of the overall radiophar-maceutical analysis is expected to be able to be improved.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.311-314
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• 2003

Under hyperosmotic stress, rCHO cells display decreased specific growth rate $({\mu})$ and increased specific antibody productivity $(q_{Ab})$. The effects of hyperosmotic stress on batch culture cellular dynamics are not well understood. To this end, we conducted a proteome profile of rCHO cells, using 2D-gel, MALDI-TOF-MS and MS/MS. As a result, the proteome profile of rCHO cells could be established using 41 identified proteins. Based on this proteome profile of rCHO cells, we have found at least 8 differently expressed spots at hyperosmotic osmolality (450 mOsm/kg). Among these spots, two metabolic enzymes were found to be up-regulated (pyruvate kinase and GAPDH), while down-regulated protein was identified as tubulin. It shows that hyperosmotic stress can alter metabolic state, by up-regulated activities of two glycolysis enzymes, which could lead to activate the generation of metabolic energy. Tubulin expression was down-regulated, suggesting a reduction of cell division. Finally, the increased conversion energy could leads to improve overall productivity.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.187-198
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• 2006

The aromatic hydrocarbons (AHs), which include benzene, polycyclic aromatic hydrocarbons, and dioxin, are important chemical and environmental contaminants in industry that usually cause various diseases. Over the years, numerous studies have described and evaluated the adverse health effects induced by AHs. Currently, "Omics" technologies, transcriptomics and proteomics, have been applied in AH toxicity studies. Proteomics has been used to identify molecular mechanisms and biomarkers associated with global chemical toxicity. It could enhance our ability to characterize chemical-induced toxicities and to identify noninvasive biomarkers. The proteomic approach (e.g. 2-dimensional electrophoresis [2-DE]), can be used to observe changes in protein expression during chemical exposure with high sensitivity and specificity. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) and electrospray ionization-quadrupole (ESI-Q)-TOF MS/MS are recognized as the most important protein identification tools. This review describes proteomic technologies and their application in the proteomic analysis of AH toxicity.

• YAKHAK HOEJI
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• v.57 no.4
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• pp.250-257
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• 2013

Biosimilars are important drugs in medicine and contain many glycosylated proteins. Thorough analysis of the glycosylated protein is a prerequisite for evaluation of biosimilar glycan drugs. A method to assess the diversity of N-glycosylation sites and N-glycans from biosimilar glycan drugs has been developed using two separate methods, LC-MS/MS and MALDI-TOF MS, respectively. Development of sensitive, accurate, and efficient methods for evaluation of glycoproteins is still needed. In this study, analysis of both N-glycosylation sites and N-glycans of glycoprotein was performed using the same LC-MS/MS with two different nano-LC columns, nano-C18 and nano-porous graphitized carbon (nano-PGC) columns. N-glycosylated proteins, including RNAse B (one N-glycosylation site), Fetuin (three sites), and ${\alpha}$-1 acid glycoprotein (four sites), were used, and small amounts of each protein were used for identification of N-glycosylation sites. In addition, high mannose N-glycans (one type of typical glycan structure), Mannose 5 and 9, eluted from RNAse B, were successfully identified using nano-PGC-LC MS/MS analysis, and the abundance of each glycan from the glycoprotein was calculated. This study demonstrated an accurate and efficient method for determination of N-glycosylation sites and N-glycans of glycoproteins based on high sensitive LC-MS/MS using two different nano-columns; this method could be applied for evaluation of the quality of various biosimilar drugs containing N-glycosylation groups.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.712-716
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• 2008

In an effort to evaluate Salmonella food safety using combinations of preservation techniques, its viabilities when exposed to HCl, acetic acid, and the oxidative agents (hydrogen peroxide and butyl hydrogen peroxide), were analyzed using sub-lethal heat-shocked Salmonella Typhimurium at $56^{\circ}C$. 2D gel electrophoresis and MALDI-TOF MS analyses were also conducted to determine the expression and repression of proteins in heat-shocked cells. Heat-shocked S. Typhimurium evidenced a reduction of viable counts by 1-2 log CFU/mL. However, viality of non heat-shocked S. Typhimurium decreased markedly by 5-6 log CFU/mL at a pH 4 in response to acid and oxidative stresses. Sub-lethal heat treatment greatly increased the resistance of S. Typhimurium against acid and oxidant agents. As for 2D gel electrophoresis and protein identification via MALDI-TOF MS, 17 major proteins in non heat-shocked S. Typhimurium were detected, and only 13 proteins among these proteins were detected in heat-shocked S. Typhimurium. The heat shock proteins such as DnaK and small heat shock proteins were included, and may be associated with the resistance of S. typhimurium against exposure to acids and oxidants. Therefore, even though the promising hurdle technology using the combined mild treatments including heat was applied to S. Typhimurium, the proper heat treatment to reduce its crossprotection activity toward the following preservative agents might be considered.

• Journal of Life Science
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• v.27 no.9
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• pp.1040-1046
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• 2017

We describe the isolation and characterization of six different intestinal microorganisms from the digestive tract of the cricket Gryllus bimaculatus. Based on 16S rRNA gene sequences, we obtained six isolates belonging to four different genera: Staphylococcus, Bacillus, Citrobacter, and Proteus. All the isolates were resistant to ampicillin. Ampicillin is an irreversible inhibitor of the enzymeetranspeptidase, which is needed to make bacterial cell walls. None of the isolates were resistant to kanamycin, which binds to the 30S subunit of the bacterial ribosome and then inhibits total protein synthesis. Gram staining was conducted, in addition to morphological classification under a microscope. Four grampositive isolates and two gram-negative isolates were detected. The gram-positive isolates were GL1 (round shaped, 2 am in diameter), GL2 (rod shaped, $2.5{\mu}m$ in length), GL3 (rod shaped, $2{\mu}m$ in length), and GL4 (round shaped, $1.5{\mu}m$ in diameter). The gram-negative isolates were GL5 (rod shaped, $2{\mu}m$ in length) and GL6 (rod-shaped, $2.5{\mu}m$ in length). Notably, two of the isolates, GL2 and GL4, secreted specific extracellular proteins. These were determined by MALDI-TOF-MS spectral analysis to be a 87 kDa collagenase, 56 kDa hypothetical protein, and 200 kDa hypothetical protein. The six isolates in this study could be used for various biotechnological applications and pest management, both in the field and in greenhouse systems. In addition, it would be interesting to determine the relationship between these isolates and their host.

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.723-727
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• 2007

Resistance to metronidazole in Helicobacter pylori results from inactivation of rdxA and frxA, the chromosomal genes for a nitroreductase that normally converts metronidazole from prodrug to bactericidal agent. Two types of metronidazole susceptible strains had been found distinguishable by their apparent levels of frxA expression. Most common in the populations we had studied were strains that required only rdxA inactivation to become resistant to moderate levels of metronidazole(type I strains). The second strain type required inactivation of both frxA and rdxA to become resistance to metronidazole(type II strains): this was linked to a relatively high level of frxA gene transcription in the type II strains. The fdxA gene regulated fdxA as well as rdxA gene. Thus, to study the function of fdxA as a regulatory gene we constructed a null mutant of fdxA in H. pylori genome and identified over-and under-expressed proteins by fdxA using two-dimensional(2-D) electrophoresis and MALDI-TOP-MS. There were four over-expressed proteins in fdxA mutant; nifU-like protein(HP0221), frxA(HP0642), nonheme ferritin(HP0653), and hypothetical protein(HP0902). Three under-expressed proteins were also identified in fdxA mutant, including 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase (HP0089), (3R)-hydroxymyristoyl ACP dehydratase(HP1376), and thioredoxin(HP1458).

• Korean Journal of Clinical Laboratory Science
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• v.50 no.3
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• pp.275-283
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• 2018

Helicobacter pylori is a causative organism of various gastrointestinal diseases, including chronic gastritis, gastric ulcer, or gastric adenocarcinoma. Pathogenic factors, such as cytotoxin-associated protein A (CagA) and vacuolating cytotoxic protein A (VacA), play a role. This study analyzed qualitatively and quantitatively the effects of zerumbone on the changes in the protein expression levels of various H. pylori proteins, including CagA and VacA. Approximately 200 significant proteins were screened for the H. pylori 60190 (VacA positive / CagA positive; Eastern type) strain, and proteomic analysis was performed on 13 protein molecules that were clinically significant. After two-dimensional electrophoresis (2-DE), $ImageMaster^{TM}$ 2-DE Platinum software was used for quantitative measurements of protein spots. Matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-TOF-MS) and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) were used for protein identification. After intensive analysis of the proteins that showed significant changes, a reverse transcription-polymerase chain reaction was performed as required to verify the results. In this study, the significance of zerumbone as a therapeutic agent for H. pylori infection was examined by screening a new pharmacological activity mechanism of zerumbone.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.2107-2109
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• 2010

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.647-654
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• 2002

The synthesis and characterization of third- and fifth-generation poly(propylene imine) dendrimers terminated with imidazole moieties is reported. Functionalization was achieved using simple peptide coupling reagents. These materials were characte rized by MALDI-MS, NMR, and titration. The use of these endgroup-functionalized dendrimers as catalysts for the hydrolysis of 2,4-dinitrophenyl acetate is described. Molecular simulations provide a basis for interpreting the catalytic data.