• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.207-217
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• 2007

The Saccharomyces0 cerevisiae KNU5377 strain, which was isolated from spoilage in nature, has the ability to convert biomass to alcohol at high temperatures and it can resist against various stresses [18, 19]. In order to understand the defense mechanisms of the KNU5377 strain under menadione (MD) as oxidative stress, we used several techniques for study: peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry (MS) followed by two-dimensional (2D) gel electrophoresis, liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), and surface-enhanced laser desorption ionization-time of flight (SELDI-TOF) technology. Among the 35 proteins identified by MALDI-TOF MS, 19 proteins including Sod1p, Sod2p, Tsa1p, and Ahp1p were induced under stress condition, while 16 proteins were augmented under normal condition. In particular, five proteins, Sod1p, Sod2p, Ahp1p, Rib3p, Yaf9p, and Mnt1p, were induced in only stressed cells. By LC-ESI-MS/MS analysis, 37 proteins were identified in normal cells and 49 proteins were confirmed in the stressed cells. Among the identified proteins, 32 proteins were found in both cells. Five proteins including Yel047cp and Met6p were only upregulated in the normal cells, whereas 17 proteins including Abp1P and Sam1p were elevated in the stressed cells. It was interesting that highly hypothetical proteins such as Ynl281wp, Ygr279cp, Ypl273wp, Ykl133cp, and Ykr074wp were only expressed in the stressed cells. SELDI-TOF analysis using the SAX2 and WCX2 chips showed that highly multiple-specific protein patterns were reproducibly detected in ranges from 2.9 to 27.0 kDa both under normal and stress conditions. Therefore, induction of antioxidant proteins, hypothetical proteins, and low molecular weight proteins were revealed by different proteomic techniques. These results suggest that comparative analyses using proteomics might contribute to elucidate the defense mechanisms of KNU5377 under MD stress.

• KSBB Journal
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• v.31 no.4
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• pp.263-269
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• 2016

For decades, the microorganisms in arctic soils have been newly discovered according to the climate change and global warming. In this study, the chemical structure of a lipid A molecule from Pseudomonas sp. strain PAMC 28615 which was newly discovered from arctic soils was characterized by mass spectrometric approaches such as matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and MALDI multi-stage tandem mass spectrometry (MS). First, lipopolysaccharide (LPS) from Pseudomonas sp. strain PAMC 28615 was extracted and subsequently hydrolyzed to obtain the lipid A. The parent ion peak at m/z 1632 was determined by MALDI-TOF MS, which also can validate our lipid A purification method. For detailed structural determination, we performed the multiple-stage tandem mass analysis ($MS^4$) of the parent ion, and subsequently the abundant fragment ions in each MS stage are tested. The fragment ions in each MS stage were produced from the loss of phosphate groups and fatty acyl groups, which could be used to confirm the composition or the position of the lipid A components. Consequently, the mass spectrometry-based lipid A profiling method could provide the detail chemical structure of lipid A from the Pseudomonas sp. strain PAMC 28615 as an arctic bacterium from the frozen arctic soil.

• 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.

• Journal of Plant Biotechnology
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• v.39 no.4
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• pp.261-272
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• 2012

Environmental factors greatly influence the growth, development, and even genetic characteristics of plants. The mechanisms by which sound influences plant growth, however, remain obscure. Previously, our group reported that several genes were differentially regulated by specific frequenciesof sound treatmentusing a sound-treated subtractive library. In this study, we used a proteomic approach to investigate plant responses to sound waves in Arabidopsis. The plants were exposed to 250-Hz or 500-Hz sound waves, and total proteins were extracted from leaves 8 h and 24 h after treatment. Proteins extracted from leaves were subjected to 2-DE analysis. Thirty-eight spots were found to be differentially regulated in response to sound waves and were identified using MALDI-TOF MS and MALDI-TOF/TOF MS. The functions of the identified proteins were classified into photosynthesis, stress and defense, nitrogen metabolism, and carbohydrate metabolism. To the best of our knowledge, this is the first report on the analysis of protein changes in response to sound waves in Arabidopsis leaves. These findings provide a better understanding of the molecular basis of responses to sound waves in Arabidopsis.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2635-2639
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• 2013

The rapid and accurate identification of biological agents is a critical step in the case of bio-terror and biological warfare attacks. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry has been widely used for the identification of microorganisms. In this study, we describe a method for the rapid and accurate discrimination of Bacillus anthracis spores using MALDI-TOF MS. Our direct in-situ analysis of MALDI-TOF MS does not involve subsequent high-resolution mass analyses and sample preparation steps. This method allowed the detection of species-specific biomarkers from each Bacillus spores. Especially, B. anthracis spores had specific biomarker peaks at 2503, 3089, 3376, 6684, 6698, 6753, and 6840 m/z. Cluster and PCA analyses of the mass spectra of Bacillus spores revealed distinctively separated clusters and within-groups similarity. Therefore, we believe that this method is effective in the real-time identification of biological warfare agents such as B. anthracis as well as other microorganisms in the field.

• Elastomers and Composites
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• v.38 no.2
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• pp.147-156
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• 2003

Synthesis of fullerene oxides by fullerenes [$C_{60},\;C_{70}$] and several oxidants such as benzoylperoxide, trichloroisocyanuric acid, methyltrioxorhenium(VII), iodosobenzene, phosphorous pentoxide take place under ultrasonic condition at room temperature. The MALDI-TOF MS,UV-visible spectra and HPLC analysis confirmed that the products of fullerenes oxidation are [$C_{60}(O)_n$], ($n=1{\sim}3$ or n=1) and [$C_{70}(O)_n$], ($n=1{\sim}2$ or n=1). As compared with the reactivity of epoxidation of fullerenes [$C_{60},\;C_{70}$], the reaction rate of $C_{70}$ was lower than that of $C_{60}$ under same reaction condition.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.833-838
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• 2012

The thermal degradation products of polytrimethylene terephthalate (PTT) obtained by heating the sample in the temperature range of $250-360^{\circ}C$ under non-oxidative conditions was characterized using MALDI-TOF (matrix assisted laser desorption/ionization) mass spectrometry. The structures of the degradation products were determined and the relative compositions were estimated. The MALDI-TOF mass spectra of the thermally degraded PTT sample showed three main series of oligomer products with different end groups, which were carboxyl/carboxyl, carboxyl/allyl, and allyl/allyl. In contrast to the thermal degradation of polyethylene terephthalate (PET), the oligomers containing terephthalic anhydrides were not detected, whereas the formation of oligomers containing the unsaturated allyl ester group was confirmed by mass assignment. From these results, it was concluded that the thermal degradation of PTT proceeds exclusively through the ${\beta}$-CH hydrogen transfer mechanism, which is in accordance with the proposed reaction mechanism for the thermal degradation of polybutylene terephthalate (PBT).

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1112-1121
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• 2018

Jeotgal is a Korean traditional fermented seafood with a high concentration of salt. In this study, we isolated lactic acid bacteria (LAB) from galchi (Trichiurus lepturus, hairtail) and myeolchi (Engraulis japonicas, anchovy) jeotgal on MRS agar and MRS agar containing 5% NaCl (MRS agar+5% NaCl), and identified them by using 16S rRNA gene sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) as culture-dependent methods. We also performed polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) as a culture-independent method to identify bacterial communities. Five samples of galchi-jeotgal and seven samples of myeolchi-jeotgal were collected from different regions in Korea. A total of 327 and 395 colonies were isolated from the galchi- and myeolchi-jeotgal samples, respectively. 16S rRNA gene sequencing and MALDI-TOF MS revealed that the genus Pediococcus was predominant on MRS agar, and Tetragenococcus halophilus on MRS agar+5% NaCl. PCR-DGGE revealed that T. halophilus, Tetragenococcus muriaticus, and Lactobacillus sakei were predominant in both types of jeotgal. T. halophilus was detected in all samples. Even though the same species were identified by both culture-dependent and -independent methods, many species identified by the culture-dependent methods were not in the bacterial list identified by the culture-independent methods. The distribution of bacteria in galchi-jeotgal was more diverse than in myeolchi-jeotgal. The diverse LAB in galchi- and myeolchi-jeotgals can be further studied as candidates for starter cultures to produce fermented foods.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.635-643
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• 2018

Bovine milk is widely consumed by humans and is a primary ingredient of dairy foods. Proteomic approaches have the potential to elucidate complex milk proteins and have been used to study milk of various species. Here, we performed a proteomic analysis using 2-dimensional electrophoresis (2-DE) and matrix assisted laser desorption ionization-time of flight mass spectrometer (MALDI-TOF MS) to identify whey proteins in bovine milk obtained soon after parturition (bovine early milk). The major casein proteins were removed, and the whey proteins were analyzed with 2-dimensional polyacrylamide gel electrophoresis (2-D PAGE). The whey proteins (2 mg) were separated by pI and molecular weight across pH ranges of 3.0 - 10.0 and 4.0 - 7.0. The 2-DE gels held about 300 to 700 detectable protein spots. We randomly picked 12 and nine spots that were consistently expressed in the pH 3.0 - 10.0 and pH 4.0 - 7.0 ranges, respectively. Following MALDI-TOF MS analysis, the 21 randomly selected proteins included proteins known to be present in bovine milk, such as albumin, lactoferrin, serum albumin precursor, T cell receptor, polymeric immunoglobulin receptor, pancreatic trypsin inhibitor, aldehyde oxidase and microglobulin. These proteins have major functions in immune responses, metabolism and protein binding. In summary, we herein identified both known and novel whey proteins present in bovine early milk, and our sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed their expression pattern.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.406.3-407
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• 2002

Analysis of interferon alpha (IFN) modified with high molecular weight branched PEG was performed by capillary electrophoresis (CE) and MALDI-TOF mass spectrometry (MALDI-TOF MS). IFN was modified by the reaction of amine residues with an active ester of monomethoxy polyethylene glycol at various molar ratios. As a CE method. capilary electrophoresis sodium dodecyl sulfate nongel sieving (CE-SDS NGS) was performed using an uncoated capilary filled with a hydrophilic replaceable polymer network matrix. (omitted)