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121.
Geon Hui Son Jiyun Moon Rahul Mahadev Shelake Uyen Thi Vuong Robert A. Ingle Walter Gassmann Jae-Yean Kim Sang Hee Kim 《International journal of molecular sciences》2021,22(12)
Plant immunity is mediated in large part by specific interactions between a host resistance protein and a pathogen effector protein, named effector-triggered immunity (ETI). ETI needs to be tightly controlled both positively and negatively to enable normal plant growth because constitutively activated defense responses are detrimental to the host. In previous work, we reported that mutations in SUPPRESSOR OF rps4-RLD1 (SRFR1), identified in a suppressor screen, reactivated EDS1-dependent ETI to Pseudomonas syringae pv. tomato (Pto) DC3000. Besides, mutations in SRFR1 boosted defense responses to the generalist chewing insect Spodoptera exigua and the sugar beet cyst nematode Heterodera schachtii. Here, we show that mutations in SRFR1 enhance susceptibility to the fungal necrotrophs Fusarium oxysporum f. sp. lycopersici (FOL) and Botrytis cinerea in Arabidopsis. To translate knowledge obtained in AtSRFR1 research to crops, we generated SlSRFR1 alleles in tomato using a CRISPR/Cas9 system. Interestingly, slsrfr1 mutants increased expression of SA-pathway defense genes and enhanced resistance to Pto DC3000. In contrast, slsrfr1 mutants elevated susceptibility to FOL. Together, these data suggest that SRFR1 is functionally conserved in both Arabidopsis and tomato and functions antagonistically as a negative regulator to (hemi-) biotrophic pathogens and a positive regulator to necrotrophic pathogens. 相似文献
122.
123.
A series of Fe-modified mordenite were hydrothermally synthesized. The effects of substrate composition, aging time, reaction
temperature, and reaction time upon the crystallization of the mordenite were investigated. Isomorphous substitution of Fe
was confirmed by FT-IR and EPR analysis. Acid strength and acid sites distribution of each catalyst were measured by pyridine
TPD, which showed that the number of strong acid sites in H-Fe-mordenite are smaller than in H-Al-mordenite. Structural characteristics
and thermal stability were also examined using XRD, SEM and TG. Fe-substitution into the mordenite structure have resulted
in substantial decrease in thermal stability. H-Fe-mordenite catalysts showed high selectivity towards p-xylene in toluene
alkylation and in xylene isomerization reaction, compared with those obtained using H-Al-mordenite because of lower concentration
of strong acid sites. In addition, these H-Fe-modified mordenite showed little hexane cracking activity. Deactivation in both
toluene alkylation and xylene isomerization reaction and coke formation over H-Fe-mordenite in these reactions were negligible. 相似文献
124.
Jeong-Yong Cho Yu Geon Lee Sang-Hyun Lee Wol-Soo Kim Keun-Hyung Park Jae-Hak Moon 《Food science and biotechnology》2014,23(1):253-259
The ethyl acetate-acidic layer obtained after solvent fractionation of Asian pear (Pyrus pyrifolia Nakai cv. Chuhwangbae) fruit peel methanol extracts was purified by Sephadex LH-20 column chromatography and octadecylsilane-high performance liquid chromatography, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity was evaluated. The four isolated compounds were identified as 2-O-(trans-p-coumaroyl) glyceric acid (1), 2-O-(cis-p-coumaroyl) glyceric acid (2), guaiacylglycerol-β-ferulic acid ether (3), and 2-O-(cis-caffeoyl) malic acid (4), based on the one- and two-dimensional nuclear magnetic resonance spectroscopic data. The isolated compounds 1–4 were identified for the first time from pear. Compound 4 showed higher DPPH radical-scavenging activity than 1–3. 相似文献
125.
Jang Hwan Kim Hyeong Min Jin Geon Gug Yang Kyu Hyo Han Taeyeong Yun Jin Yong Shin Seong‐Jun Jeong Sang Ouk Kim 《Advanced functional materials》2020,30(2)
Nanoscale fabrication of smart materials relying on the molecular self‐assembly of block copolymers (BCPs) has been recognized as a valuable platform for various next‐generation functional structures. In this Progress Report, the recent advances in the BCP self‐assembly process, which has paved the way for viable applications of emerging nanotechnologies, are highlighted. Effective light‐induced self‐assembly based on photothermal annealing of high‐χ BCPs and conformal 3D surface nanopatterning exploiting chemically modified graphene flexible substrates are reviewed as the typical instances of advanced BCP‐based nanofabrication methodologies. Additionally, relevant potential application fields are suggested, namely, graphene nanoribbon field effect transistors, highly tunable refractive index metasurfaces for visible light, high‐sensitivity surface‐enhanced Raman spectroscopy, 2D transition metal dichalcogenide nanopatterning, sequential infiltration synthesis, and organic photovoltaics. Finally, the future research direction as well as innovative applications of these smart nanostructured materials is proposed. 相似文献
126.
Ji Bong Joo Ilkeun Lee Michael Dahl Geon Dae Moon Francisco Zaera Yadong Yin 《Advanced functional materials》2013,23(34):4246-4254
TiO2 hollow shells with well‐controlled crystallinity, phase, and porosity are desirable in many applications. In photocatalysis in particular, they can provide high active surface area, reduced diffusion resistance, and improved accessibility to reactants. Here, the results from studies of the causes for the failure of a prior etching and calcination scheme to make such shells and on a newly‐developed simple yet robust process for producing uniform mesoporous TiO2 shells with precisely controllable crystallinity and phase are reported. The key finding is that base etching of the SiO2@TiO2 core‐shell particles leads to the formation of sodium titanate species, which, if not removed, promote substantial crystal growth during calcination and destroy the structural integrity of the TiO2 shells. A simple acid treatment of the base‐etched samples may convert the sodium titanates into protonated titanates, which not only prevent the formation of the impurity phases, but also help to maintain the structural integrity of the shell and allow precise control of the TiO2 phase and crystallinity. This new development affords convenient optimization of the structure of the hollow TiO2 shells toward efficient photocatalysts, which outperform the commercial P25‐TiO2 in the photocatalytic decomposition of organic dye molecules. 相似文献