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71.
72.
Hyo Je Cho Kyungsun Kim Seo Yean Sohn Ha Yeon Cho Kyung Jin Kim Myung Hee Kim Dockyu Kim Eungbin Kim Beom Sik Kang 《The Journal of biological chemistry》2010,285(45):34643-34652
A meta-cleavage pathway for the aerobic degradation of aromatic hydrocarbons is catalyzed by extradiol dioxygenases via a two-step mechanism: catechol substrate binding and dioxygen incorporation. The binding of substrate triggers the release of water, thereby opening a coordination site for molecular oxygen. The crystal structures of AkbC, a type I extradiol dioxygenase, and the enzyme substrate (3-methylcatechol) complex revealed the substrate binding process of extradiol dioxygenase. AkbC is composed of an N-domain and an active C-domain, which contains iron coordinated by a 2-His-1-carboxylate facial triad motif. The C-domain includes a β-hairpin structure and a C-terminal tail. In substrate-bound AkbC, 3-methylcatechol interacts with the iron via a single hydroxyl group, which represents an intermediate stage in the substrate binding process. Structure-based mutagenesis revealed that the C-terminal tail and β-hairpin form part of the substrate binding pocket that is responsible for substrate specificity by blocking substrate entry. Once a substrate enters the active site, these structural elements also play a role in the correct positioning of the substrate. Based on the results presented here, a putative substrate binding mechanism is proposed. 相似文献
73.
74.
Effect of abscisic acid application on root isoflavonoid concentration and nodulation of wild-type and nodulation-mutant soybean plants 总被引:1,自引:0,他引:1
Isoflavonoids (daidzein, genistein, and coumestrol) are involved in induction of nod genes in Bradyrhizobium japonicum and may be involved in nodule development as well. Abscisic acid (ABA) may also impact nodulation since ABA is reportedly
involved in isoflavonoid synthesis. The current study was conducted to evaluate whether ABA plays a role in differential nodulation
of a hypernodulated soybean (Glycine max L. Merr.) mutant and the Williams parent. Exogenous ABA application resulted in a decrease in nodule number and weight in
both lines. Isoflavonoid concentrations were also markedly decreased in response to ABA application in both inoculated and
noninoculated soybean roots. The inoculation treatment itself resulted in a marked increase in isoflavonoid concentrations
of NOD1-3, regardless of ABA levels, while only slight increases occurred in Williams. The nodule numbers of both soybean
lines across several ABA concentration treatments were highly correlated with the concentration of all three isoflavonoids.
However, differences in internal levels of ABA between lines were not detected when grown in the absence of external ABA additions.
It is concluded that differential nodule expression between the wild type and the hypernodulated mutant is not likely due
to differential ABA synthesis. 相似文献
75.
76.
Anne Durand Fabien Chauveau Tae-Hee Cho Radu Bolbos Jean-Baptiste Langlois Laure Hermitte Marlène Wiart Yves Berthezène Norbert Nighoghossian 《PloS one》2012,7(11)
Injection of thrombin into the middle cerebral artery (MCA) of mice has been proposed as a new model of thromboembolic stroke. The present study used sequential multiparametric Magnetic Resonance Imaging (MRI), including Magnetic Resonance Angiography (MRA), Diffusion-Weighted Imaging (DWI) and Perfusion-Weighted Imaging (PWI), to document MCA occlusion, PWI-DWI mismatch, and lesion development. In the first experiment, complete MCA occlusion and reproducible hypoperfusion were obtained in 85% of animals during the first hour after stroke onset. In the second experiment, 80% of animals showed partial to complete reperfusion during a three-hour follow-up. Spontaneous reperfusion thus contributed to the variability in ischemic volume in this model. The study confirmed the value of the model for evaluating new thrombolytic treatments, but calls for extended MRI follow-up at the acute stage in therapeutic studies. 相似文献
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78.
Yong Jun Gong Jung Woon Heo Hakji Lee Hyunjin Kim Jinil Cho Seonmi Pyo Heejun Yun Heebae Kim Sang Yoon Park Jeeyoung Yoo Youn Sang Kim 《Liver Transplantation》2020,10(27)
Li metal, which has a high theoretical specific capacity and low redox potential, is considered to the most promising anode material for next‐generation Li ion‐based batteries. However, it also exhibits a disadvantageous solid electrolyte interphase (SEI) layer problem that needs to be resolved. Herein, an advanced separator composed of reduced graphene oxide fiber attached to aramid paper (rGOF‐A) is introduced. When rGOF‐A is applied, F? anions, generated from the decomposition of the LiPF6 electrolyte during the SEI layer formation process form semi‐ionic C? F bonds along the surface of rGOF. As Li+ ions are plated, the “F‐doped” rGO surface induces the formation of LiF, which is known as a component of a chemically stable SEI, therefore it helps the Li metal anode to operate stably at a high current of 20 mA cm?2 with a high capacity of 20 mAh cm?2. The proposed rGOF‐A separator successfully achieves a stable SEI layer that could resolve the interfacial issues of the Li metal anode. 相似文献
79.
Woo Yong Sung Ji Won Yu Jong Tae Hwang Hee Jin Nam Ji Ye Park Yongae Kim Jang‐Hee Cho 《Journal of peptide science》2020,26(8)
Antimicrobial peptides are class of small, positively charged peptides known for their broad‐spectrum antimicrobial activity. Antimicrobial activities for most antimicrobial peptides have largely remained elusive, particularly in the lactic acid bacteria. However, recently our investigation using LPcin‐YK3, an antimicrobial peptide from bovine milk, suggests that in vitro antimicrobial activity was reduced over 100‐fold compared with pathogenic bacteria. Additionally, for the structural study of how antimicrobial peptide undergoes its reaction at the proteolytic pathway of lactic acid bacteria based on degradation assay and propidium iodide staining, we performed molecular docking for interaction between oligopeptide‐binding protein A and LPcin‐YK3 peptide. Given that degradation related to the LPcin‐YK3 peptide in lactic acid bacteria proteolytic system, the inhibitory inactivity of LPcin‐YK3 against beneficial lactic acid bacteria strains may be one of the primary pharmacological properties of recombinant peptide discovered in bovine milk. These results provide structural and functional insights into the proteolytic mechanism and possibility as a putative substrate of oligopeptide‐binding protein A in respect of LPcin‐YK3 peptide. 相似文献
80.
Hyoung-Min Park HuiSu Kim Dong Wook Kim Jong-Hyuk Yoon Byung-Gyu Kim Je-Yoel Cho 《BMB reports》2020,53(12):664
Breast cancer is one of the most frequently diagnosed cancers. Although biomarkers are continuously being discovered, few specific markers, rather than classification markers, representing the aggressiveness and invasiveness of breast cancer are known. In this study, we used samples from canine mammary tumors in a comparative approach. We subjected 36 fractions of both canine normal and mammary tumor plasmas to high-performance quantitative proteomics analysis. Among the identified proteins, LCAT was selectively expressed in mixed tumor samples. With further MRM and Western blot validation, we discovered that the LCAT protein is an indicator of aggressive mammary tumors, an advanced stage of cancer, possibly highly metastatic. Interestingly, we also found that LCAT is overexpressed in high-grade and lymphnode-positive breast cancer in silico data. We also demonstrated that LCAT is highly expressed in the sera of advanced-stage human breast cancers within the same classification. In conclusion, we identified a possible common plasma protein biomarker, LCAT, that is highly expressed in aggressive human breast cancer and canine mammary tumor. 相似文献