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Incheon, South Korea

Lee K.,SongDo Techno Park | Rho B.-S.,SongDo Techno Park | Kim H.-J.,SongDo Techno Park | Choi Y.-J.,Seoul National University
Journal of Biotechnology | Year: 2011

Lactobacillus plantarum, a probiotic organism that plays an important role in the microbial fermentation of alkaline materials in fermenting foods, faces alkaline stress during the fermentation process. Here, we report the patterns of protein expression in . L. plantarum subjected to transient (1. h) alkaline stress at pH 7.7, 8.7 or 9.7. Thirty-three alkaline-responsive proteins were identified by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS). Identification of proteins showing differential expression in response to alkaline stress revealed that the alkaline stress response of . L. plantarum is a complex process. Some proteins appear to be induced, others repressed. These proteins could be clustered into nine groups based on their probable functions: energy metabolism, transport system, purine/pyrimidine metabolism, amino acid metabolism, proteolytic activity, transcription-translation, stress-related, general function, and unknown functions. These proteomic analyses are expected to prove useful in understanding the adaptive response of . L. plantarum strains to alkaline stress and may facilitate future investigations into the genetic and physiological aspects of this response. © 2011 Elsevier B.V. Source

Jin Y.-C.,Seoul National University | Lee H.-G.,Pusan National University | Xu C.-X.,Emory University | Han J.-A.,Seoul National University | And 9 more authors.
Biochimica et Biophysica Acta - Proteins and Proteomics | Year: 2010

This study was conducted to investigate the amount of CLA synthesized endogenously by rat mammary tissues in response to TVA (a precursor for cis-9, trans-11 CLA endogenous synthesis) treatment as well as the differences in the protein expression of genes encoding the biosynthesis of CLA in rat mammary tissue and mouse mammary gland epithelia cells (HC11). Treatment with TVA resulted in improved CLA productivity. Furthermore, 2-DE revealed two spots in samples of mammary tissues and one spot in samples of mammary gland epithelia cells (HC11) that were consistently altered in the TVA treatment groups when compared with the control group (non-fatty acid). The mRNA expression patterns of three of the proteins (PDI, PRDX2, LAMR1), as measured by real-time PCR, were similar to the pattern of protein abundance. In addition, the expression of SCD mRNA in the mammary tissue of rats and HC11 cell treated with TVA was higher than in the control group. Our results suggest that the identified proteins may be related to CLA biosynthesis in mammary tissue. Crown Copyright © 2009. Source

Lee K.B.,SongDo Techno Park
Biomeditsinskaya Khimiya | Year: 2010

Lung cancer is the leading cause of cancer-related mortality in industrialized countries. Unfortunately, most lung cancers are found too late for a cure, therefore early detection and treatment is very important. We have applied proteomic analysis by using two-dimensional gel electrophoresis and peptide mass fingerprinting techniques for examination of cancerous and adjacent non-cancerous lung tissues from the same patient. The aim of the study was to find proteins, which could be used as biomarkers for diagnosis and monitoring of this disease. Indeed, we found differences in expression of several proteins, related to various cellular activities, such as, chaperoning (e,g. GRP96, GRP78, HSP27), metabolism and oxidation stress (e.g. L-fucose, GST), cytoskeleton (e.g., tubulin beta 2/3, beta actin), cell adhesion (e.g. annexin A5/3), binding proteins (e.g. 14-3-3 theta) and signal transduction. These changes may be important for progression of carcinogenesis; they may be used as the molecular-support for future diagnostic markers. Source

Lee H.,Pusan National University | Han J.,Seoul National University | Lee K.,SongDo Techno Park | Kim E.,Seoul National University | And 9 more authors.
Food Science and Biotechnology | Year: 2010

Because beef contains a high proportion of marbling, we sought to optimize the solubilization of the longissimus muscle proteome using modified lysis and isoelectric focusing (IEF) rehydration buffers. Of the 3 lysis buffers tested, those containing a thiourea-urea mixture provided superior resolution, whereas that which contained only urea yielded consistently poor results. In addition, we found that the IEF rehydration buffer containing a thiourea-urea mixture, a high dithiothreitol level, and Pharmalyte was able to generate sharper 2-dimensional (2-D) gels, whereas that which contained immobilized pH gradient (IPG) buffer had no an effect on protein resolution. The number of different protein spots between the muscle-development stage (11 months) and the fat-development stage (17 months) in Hanwoo steers was 39, whereas the use of normal buffer resulted in a detection of a difference of only 7 protein spots. This study provides a methodological tool for studying the proteome of bovine longissimus muscle with a high fat content using 2-D gel electrophoresis (2-DE) gels. © KoSFoST and Springer 2010. Source

Jin Y.C.,Jilin University | Jin Y.C.,Pusan National University | Li Z.H.,Seoul National University | Hong Z.S.,Tianjin Agricultural University | And 12 more authors.
Journal of Dairy Science | Year: 2012

This study was conducted to identify proteins associated with the endogenous synthesis of conjugated linoleic acid (CLA) from trans-vaccenic acid (TVA; trans-11 C18:1, a precursor for CLA endogenous synthesis) in mammary tissues. Six lactating goats were divided into 2 groups. One group was given an intravenous bolus injection of TVA (150. mg) twice daily over 4 d; the other group received saline injections. Treatment with TVA increased the concentration of cis-9,. trans-11 CLA and TVA in goat milk. Additionally, TVA treatment increased the expression of stearoyl-CoA desaturase (SCD) in mammary tissue. Using 2-dimensional gel electrophoresis and electrospray ionization quadrupole time-of-flight mass spectrometry, 3 proteins affected by infusions of TVA were identified. Proteasome (prosome, macropain) subunit α type 5 (PSMA5) was upregulated, whereas peroxiredoxin-1 and translationally controlled tumor protein 1 were downregulated in TVA-treated animals compared with the vehicle-injected controls. Only the effect of TVA on PSMA5 could be confirmed by Western blot analysis. To further explore the regulation of PSMA5 in mammary epithelial cells when TVA is converted into CLA, we used a differentiated bovine mammary epithelial cell line treated with TVA for 6. h. Changes in cis-9,. trans-11 CLA concentrations and mRNA expression patterns of both SCD and PSMA5 were monitored. The concentration of cis-9,. trans-11 CLA increased after TVA treatment. The mRNA expression level of PSMA5 was significantly elevated to 6. h, but SCD mRNA expression only increased in 2. h after TVA treatment. These results indicate that PSMA5 is highly expressed in goat mammary tissue and bovine mammary epithelial cells when TVA is converted into CLA. Our data suggest that PSMA5 protein is associated with CLA biosynthesis in mammary tissue. © 2012 American Dairy Science Association. Source

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