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131.
Ae Kyung Park Jin Ho Moon Eun Hyuk Jang Hyun Park In Young Ahn Ki Seog Lee Young Min Chi 《Proteins》2013,81(3):531-537
Glutathione‐S‐transferases have been identified in all the living species examined so far, yet little is known about their function in marine organisms. In a previous report, the recently identified GST from Antarctic bivalve Laternula elliptica (LeGST) was classified into the rho class GST, but there are several unique features of LeGST that may justify reclassification, which could represent specific shellfish GSTs. Here, we determined the crystal structure of LeGST, which is a shellfish specific class of GST. The structural analysis showed that the relatively open and wide hydrophobic H‐site of the LeGST allows this GST to accommodate various substrates. These results suggest that the H‐site of LeGST may be the result of adaptation to their environments as sedentary organisms. Proteins 2013. © 2012 Wiley Periodicals, Inc. 相似文献
132.
In the present work, we report a comprehensive vibrational circular dichroism (VCD) spectroscopic study of a chiral crown ether which features an axial chiral 3.3'‐diphenyl‐1,1'‐binaphthyl group as chiral moiety. By comparing the experimental and calculated VCD spectra, we show that the presumably very flexible crown ether preferably adopts only one ring conformation. Conformational flexibility is observed in the 2,4‐dinitrophenyl‐diazophenol group, which was previously introduced for colorimetric detection of primary amines and amino alcohols (Cho et al., Chirality 2011;23:349–353). The VCD spectra of the host–guest complexes with phenyl glycinol (PG) and phenyl alaninol have been studied as well. Based on the spectra calculated, it is shown that the diastereomeric complexes in general can be differentiated using VCD spectroscopy. Furthermore, the experimental VCD spectra of the complexes of the host molecule with PG support the above finding. Chirality 25:294–300, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
133.
Neelesh Sharma Jeong Hyun Kim Simrinder Singh Sodhi Do Huynh Luong Sung-Woo Kim Sung Jong Oh 《Journal of biomolecular structure & dynamics》2013,31(12):2633-2654
The “stem cells” are commonly defined as “cells capable of self-renewal through replication and differentiating into specific lineages”. The mammary gland contains functional stem/progenitor cells. The current study was planned with the objectives to study the differentiation dynamics of Korean Holstein mammary epithelial stem cells (KHMESCs) under the optimum culture conditions. Lineage negative KHMESCs isolated from mammary tissue of lactating cows have shown the typical differentiation dynamics with formation of lobulo–alveolar structures in in vitro culture. This suggests the existence of bipotential mammary epithelial stem cells in the mammary gland. The strong mRNA expression of pluripotency factors indicates stemness, whereas expression of milk protein genes and epithelial cell-specific gene indicate their differentiation capabilities. Further, immunostaining results have shown the differentiation capabilities of KHMESCs into both luminal and basal lineages under the extracellular matrix (ECM, matrigel) free environment. However, under matrigel, the differentiation process was comparatively higher than without matrigel. Immunostaining results also suggested that differentiated cells could secrete milk proteins such as β-casein. To our knowledge, these data represent the first report on the differentiation dynamics and establishment of mammary epithelial stem cells from Korean Holstein with typical stemness properties. It was observed that isolated KHMESCs had normal morphology, growth pattern, differentiation ability, cytogenetic and secretory activity even without ECM. Therefore, it is concluded that established KHMESCs could be used for further studies on Korean Holstein dairy cows related to lactation studies, as non-GMO animal bioreactors and stem cell-based management of bovine mastitis including post-mastitis damage. 相似文献
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136.
Seung Hwan Lee Kyoung-Hee Kang Eun Young Kim Tong Un Chae Young Hoon Oh Soon Ho Hong Bong Keun Song Jonggeon Jegals Si Jae Park Sang Yup Lee 《Biotechnology letters》2013,35(10):1631-1637
We have previously analyzed the proteome of recombinant Escherichia coli producing poly(3-hydroxybutyrate) [P(3HB)] and revealed that the expression level of several enzymes in central metabolism are proportional to the amount of P(3HB) accumulated in the cells. Based on these results, the amplification effects of triosephosphate isomerase (TpiA) and fructose-bisphosphate aldolase (FbaA) on P(3HB) synthesis were examined in recombinant E. coli W3110, XL1-Blue, and W lacI mutant strains using glucose, sucrose and xylose as carbon sources. Amplification of TpiA and FbaA significantly increased the P(3HB) contents and concentrations in the three E. coli strains. TpiA amplification in E. coli XL1-Blue lacI increased P(3HB) from 0.4 to 1.6 to g/l from glucose. Thus amplification of glycolytic pathway enzymes is a good strategy for efficient production of P(3HB) by allowing increased glycolytic pathway flux to make more acetyl-CoA available for P(3HB) biosynthesis. 相似文献
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Jooyeon Woo Seok-Kyu Kwon Jungyong Nam Seungwon Choi Hideto Takahashi Dilja Krueger Joohyun Park Yeunkum Lee Jin Young Bae Dongmin Lee Jaewon Ko Hyun Kim Myoung-Hwan Kim Yong Chul Bae Sunghoe Chang Ann Marie Craig Eunjoon Kim 《The Journal of cell biology》2013,201(6):929-944
Synaptic adhesion molecules regulate diverse aspects of synapse formation and maintenance. Many known synaptic adhesion molecules localize at excitatory synapses, whereas relatively little is known about inhibitory synaptic adhesion molecules. Here we report that IgSF9b is a novel, brain-specific, homophilic adhesion molecule that is strongly expressed in GABAergic interneurons. IgSF9b was preferentially localized at inhibitory synapses in cultured rat hippocampal and cortical interneurons and was required for the development of inhibitory synapses onto interneurons. IgSF9b formed a subsynaptic domain distinct from the GABAA receptor– and gephyrin-containing domain, as indicated by super-resolution imaging. IgSF9b was linked to neuroligin 2, an inhibitory synaptic adhesion molecule coupled to gephyrin, via the multi-PDZ protein S-SCAM. IgSF9b and neuroligin 2 could reciprocally cluster each other. These results suggest a novel mode of inhibitory synaptic organization in which two subsynaptic domains, one containing IgSF9b for synaptic adhesion and the other containing gephyrin and GABAA receptors for synaptic transmission, are interconnected through S-SCAM and neuroligin 2. 相似文献
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140.
Dong Hyun Kim Nitin Puri Komal Sodhi John R. Falck Nader G. Abraham Joseph Shapiro Michal L. Schwartzman 《Journal of lipid research》2013,54(3):786-793
20-Hydroxy-5,8,11,14-eicosatetraenoic acid (20-HETE), a product of the cytochrome
P450 (CYP)-catalyzed ω-hydroxylation of arachidonic acid, induces
oxidative stress and, in clinical studies, is associated with increased body
mass index (BMI) and the metabolic syndrome. This study was designed to examine
the effects of exogenous 20-HETE on mesenchymal stem cell (MSC)-derived
adipocytes. The expression levels of CYP4A11 and CYP4F2 (major 20-HETE synthases
in humans) in MSCs decreased during adipocyte differentiation; however,
exogenous administration of 20-HETE (0.1–1 μM) increased adipogenesis
in a dose-dependent manner in these cells (P < 0.05). The
inability of a 20-HETE analog to reproduce these effects suggested the
involvement of a metabolic product of 20-HETE in mediating its pro-adipogenic
effects. A cyclooxygenase (COX)-1 selective inhibitor enhanced, whereas a COX-2
selective or a dual COX-1/2 inhibitor attenuated adipogenesis induced by
20-HETE. The COX-derived metabolite of 20-HETE, 20-OH-PGE2, enhanced
adipogenesis and lipid accumulation in MSCs. The pro-adipogenic effects of
20-HETE and 20-OH-PGE2 resulted in the increased expression of the
adipogenic regulators PPARγ and β-catenin in MSC-derived adipocytes.
Taken together we show for the first time that 20-HETE-derived COX-2-dependent
20-OH-PGE2 enhances mature inflamed adipocyte hypertrophy in MSC
undergoing adipogenic differentiation. 相似文献