• BMB Reports
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• 제39권6호
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• pp.703-708
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• 2006

During infection, the common respiratory tract pathogen Streptococcus pneumoniae encounters several environmental conditions, such as upper respiratory tract, lung tissue, and blood stream, etc. In this study, we examined the effects of blood on S. pneumoniae protein expression using a combination of highly sensitive 2-dimensional electrophoresis (DE) and MALDI-TOF MS and/or LC/ESI-MS/MS. A comparison of expression profiles between the growth in THY medium and THY supplemented with blood allowed us to identify 7 spots, which increased or decreased two times or more compared with the control group: tyrosyl-tRNA synthetase, lactate oxidase, glutamyl-aminopeptidase, L-lactate dehydrogenase, cysteine synthase, ribose-phosphate pyrophosphokinase, and orotate phosphoribosyltransferase. This global approach can provide a better understanding of S. pneumoniae adaptation to its human host and a clue for its pathogenicity.

• Journal of Microbiology
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• 제43권2호
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• pp.191-195
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• 2005

In this study, we attempted to characterize the Synechococcus sp. pee 7942 mutant resultant from a disruption in the gene encoding UDP-glucose: tetrahydrobiopterin a-glucosyltransferase (BGluT). 2D­PAGE followed by MALDI-TOF mass spectrometry revealed that phycocyanin rod linker protein 33K was one of the proteins expressed at lower level in the BGluT mutant. BGluT mutant cells were also determined to be more sensitive to high light stress. This is because photosynthetic O$_2$ exchange rates were significantly decreased, due to the reduced number of functional PSIs relative to the wild type cells. These results suggested that, in Synechococcus sp. pee 7942, BH4-glucoside might be involved in photosynthetic photoprotection.

• Food Science and Biotechnology
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• 제14권6호
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• pp.854-859
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• 2005

Although action modes of equol and genistein have been extensively studied, their precise roles in tumor cells remain elusive. To address possible effects of these compounds on protein expression in mammary tumor cells, proteins modulated in MCF-7 mammary tumor cells when incubated in absence and presence of 10 uM equol or genistein were identified through 2-dimensional gel electrophoresis, MALDI-TOF MS/MS, and NCBInr database search using Mascot software. Most proteins differentially expressed in MCF-7 cells after treatment with 10 uM genistein or equol were identified as being the same. Exposure to both compounds caused decreased cellular expression of RNA-binding protein regulatory subunit and oncogene DJ1 tubulin beta-1 chain, and increased expression of heterogeneous ribonucleoproteins F and L, KH-type splicing regulatory protein, and translation elongation factor EF-Tu precursor. Genistein and equol at dose used in this study showed common action mechanism.

• Food Science and Biotechnology
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• 제18권2호
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• pp.519-525
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• 2009

A bacterial strain (Strain N-08) capable of extracellularly producing high level of non-reducing oligosaccharide (NR-OS) isolated from soil. The strain was identified phylogenetically by 16S rDNA sequence analysis and found to be very close to Arthrobacter crystallopoietes. The high production of NR-OS was observed in the basal culture medium containing maltose as a sole carbon source. The NR-OS in culture supernatant was purified by glucoamylase treatment and Dowex-1 (OH.) ion exchange chromatography and its structure was characterized. This oligosaccharide consisted of only glucose. Methylation analysis indicated that this fraction was composed mainly of non-reducing terminal glucopyranoside. Matrixassisted laser-induced/ionization time-of-flight (MALDI-TOF) and electrospray ionization-mass spectrometry (ESI-MS)/MS analyses suggested that this oligosaccharide comprised non-reducing disaccharide unit with 1,1-glucosidic linkage. When this disaccharide was analyzed by $^1H$-NMR and $^{13}C$-NMR, it gave the same signals with $\alpha$-D-glucopyranosyl-(1,1)-$\alpha$-Dglucopyranoside. These results indicated that the NR-OS produced by A. crystallopoietes N-08 was ${\alpha}1$,${\alpha}1$-trehalose. This is the first report of the trehalose which can be produced directly from maltose by A. crystallopoietes N-08.

• 한국축산시설환경학회지
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• 제20권2호
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• pp.77-84
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• 2014

This study was conducted to investigate the bacterial capability to accumulate phosphorus during liquid composting process of pig slurry. Storage liquid compost and pig slurry were analyzed by using MALDI-TOF technique, which showed the colonies of Acinetobacter towneri and Bacillus licheniformis. In addition, bacterial colonies were isolated under high phosphoric acid conditions using X-phosphate MOPS medium with the addition of 2 mM $K_2HPO_4$. Microbial growth was observed in high and low phosphoric conditions due to the growth of bacterial diversities in the liquid fertilizer and slurry. The colonies isolated in the high phosphoric acid medium were uncultured bacterium clone and Acinetobacter sp. were identified by analysis of 16S rRNA gene sequences. Uncultured bacterium showed higher growth rate and excellent phosphorus ability then Acinetobacter sp.. In addition to Paenibacillus sp. AEY-1 isolated from pig slurry performed excellent phosphorus utilizing capability.

• Molecules and Cells
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• 제22권1호
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• pp.36-43
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• 2006

Mesenchymal stem cells (MSCs) are promising candidates for cell therapy and tissue engineering, but their application has been impeded by lack of knowledge of their core biological properties. In order to identify MSC-specific proteins, the hydrophobic protein fraction was individually prepared from two different umbilical cord blood (UCB)-derived MSC populations; these were then subjected to two-dimensional (2D) gel electrophoresis and peptide mass fingerprinting matrix-assisted laser desorption/ionization (MALDI)-time of flight (TOF)-mass spectrometry (MS). Although the 2D gel patterns differed somewhat between the two samples, computer-assisted image analysis identified shared protein spots. 35 spots were reliably identified corresponding to 32 different proteins, many of which were chaperones. Based on their primary sub-cellular locations the proteins could be grouped into 6 categories: extracellular, cell surface, endoplasmic reticular, mitochondrial, cytoplasmic and cytoskeletal proteins. This map of the water-insoluble proteome may provide valuable insights into the biology of the cell surface and other compartments of human MSCs.

• Bulletin of the Korean Chemical Society
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• 제29권4호
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• pp.761-766
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• 2008

Photoresponsive arylether dendrimers Bis-azo-Gn(3,5) 1a-1c and Bis-azo-Gn(3,4,5) 2a-2c (n = 1-3) with an azobenzene unit at the core and several vinyl groups (3,5-bis(but-3-enyloxy)phenyl groups or 3,4,5-tris(but-3- enyloxy)phenyl groups) at the periphery have been prepared. Their structures and reversible trans-cis isomerization behaviors have been investigated by $^1H$-NMR, $^{13}C$-NMR, MALDI-TOF-Mass, and UV-vis spectra. All six azobenzene-cored dendrimers carried out very fast trans $\rightarrow$ cis photoisomerization on irradiation of 350 nm light and reached to the photostationary state within 180 s. During the dark incubation, slow thermal back reversion from cis to trans form is observed for all six dendrimers and is completed within 3 days for 1a-1c and 1 day for 2a-2c. Isomerization efficiency decreases with increasing generation. However, the initial reaction rates of both trans $\rightarrow$ cis photochemical isomerization and cis $\rightarrow$ trans thermal isomerization increases significantly with increasing generation for dendrimers for 1a-1c but only slightly for 2a-2c.

• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1120-1126
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• 2013

The syndecan family consists of four transmembrane heparan sulfate proteoglycans present in most cell types and each syndecan shares a common structure containing a heparan sulfate modified extracellular domain, a single transmembrane domain and a C-terminal cytoplasmic domain. To get a better understanding of the mechanism and function of syndecan-4 which is one of the syndecan family, it is crucial to investigate its three-dimensional structure. Unfortunately, it is difficult to prepare the peptide because it is membrane-bound protein that transverses the lipid bilayer of the cell membrane. Here, we optimize the expression, purification, and characterization of transmembrane, cytoplasmic and short extracellular domains of syndecan4 (syndecan-4 eTC). Syndecan-4 eTC was successfully obtained with high purity and yield from the M9 medium. The structural information of syndecan-4 eTC was investigated by MALDI-TOF mass (MS) spectrometry, circular dichroism (CD) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. It was confirmed that syndecan-4 eTC had an ${\alpha}$-helical multimeric structure like transmembrane domain of syndecan-4 (syndecan-4 TM) in membrane environments.

• Macromolecular Research
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• 제17권6호
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• pp.424-429
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• 2009

In this study, we demonstrate that the biological unnatural amino acid incorporation method can be utilized in vivo to synthesize an alkyne-terminated telechelic protein, Synthesis of terminally-functionalized polymers such as telechelic polymers is recognized to be important, since they can be employed usefully in many areas of biology and material science, such as drug delivery, colloidal dispersion, surface modification, and formation of polymer network. The introduction of alkyne groups into polymeric material is particularly interesting since the alkyne group can be a linker to combine other materials using click chemistry. To synthesize the telechelic recombinant protein, we attempted to incorporate the L-homopropargylglycine into the recombinant GroES fragment by expressing the recombinant gene encoding Met at the codons for both N- and C-terminals of the protein in the Met auxotrophic E. coli via Hpg supplementation. The Hpg incorporation rate was investigated and the incorporation was confirmed by MALDI-TOF analysis of the telcchelic recombinant protein.

• Journal of Microbiology and Biotechnology
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• 제23권3호
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• pp.390-396
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• 2013

Biosurfactants have versatile properties and potential industrial applications. A new producer, B. subtilis TU2, was isolated from the underground oil-extraction wastewater of Shengli Oilfield, China. Preliminary flask culture showed that the titer of biosurfactant obtained from the broth of TU2 was ~1.5 g/l at 48 h (718 mg/l after purification), with a reduced surface tension of 32.5 mN/m. The critical micelle concentration was measured as 50 mg/l and the surface tension maintained stability in solution with 50 g/l NaCl and 16 g/l $CaCl_2$ after 5 days of incubation at $70^{\circ}C$. FT-IR spectra exhibited the structure information of both glycolipid and lipopeptide. MALDI-TOF-MS analyses confirmed that the biosurfactant produced by B. subtilis TU2 was a blend of glycolipid and lipopeptide, including rhamnolipid, surfactin, and fengycin. The blended biosurfactant showed 86% of oil-washing efficiency and fine emulsification activity on crude oil, suggesting its potential application in enhanced oil recovery.