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1.
Microorganisms ; 12(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38674624

RESUMO

Hexose transporters (HXT) play a crucial role in the pathogenicity of Magnaporthe oryzae, serving not only as key facilitators for acquiring and transporting sugar nutrients to support pathogen development, but also as sugar sensors which receive transduction signals. The objective of this study is to investigate the impact of MoHXT1-3 on rice pathogenicity and hexose affinity. MoHXT1-3 deletion mutants were generated using CRISPR/Cas9 technology, and their affinity for hexose was evaluated through yeast complementation assays and electrophysiological experiments in Xenopus oocytes. The results suggest that MoHXT1 does not contribute to melanin formation or hexose transportation processes. Conversely, MoHXT2, despite displaying lower affinity towards the hexoses tested in comparison to MoHXT3, is likely to have a more substantial impact on pathogenicity. The analysis of the transcription profiles demonstrated that the deletion of MoHXT2 caused a decrease in the expression of MoHXT3, whereas the knockout of MoHXT3 resulted in an upregulation of MoHXT2 transcription. It is noteworthy that the MoHXT2M145K variant displayed an incapacity to transport hexoses. This investigation into the functional differences in hexose transporters in Magnaporthe oryzae provides insights into potential advances in new strategies to target hexose transporters to combat rice blast by blocking carbon nutrient supply.

2.
J Colloid Interface Sci ; 665: 399-412, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38537588

RESUMO

Photocatalytic selective oxidation plays an important role in developing green chemistry. However, it is challenging to design an efficient photocatalyst for controlling the selectivity of photocatalytic oxidation reaction and exploring its detailed mechanism. Here, we synthesized three conjugated microporous polymers (CMPs) with D-A structures, named M-SATE-CMPs (MZn, Cu and Co), with different d-band centers based on different metal centers, resulting in the discrepancy in adsorption and activation capacities for the reactants, which produces the selectivity of ß-keto esters being catalyzed into α-hydroperoxide ß-keto esters (ROOH) or to α-hydroxyl ß-keto esters (ROH). Density functional theory (DFT) calculations also demonstrate that the adsorption and activation capacities of the metal active centers in M-SATE-CMPs (MZn, Cu and Co) for ROOH are the key factors to influence the photocatalytic selective oxidation of ß-keto ester. This study provides a promising strategy for designing a metallaphotoredox catalyst whose photocatalytic selectivity depends on the d-band center of metal site in the catalyst.

3.
Plant Biotechnol J ; 20(10): 1888-1901, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35678495

RESUMO

Characterization and genetic engineering of plant transporters involved in the pesticide uptake and translocation facilitate pesticide relocation to the tissue where the pests feed, thus improving the bioavailability of the agrichemicals. We aimed to identify thiamethoxam (THX) transporters in rice and modify their expression for better brown planthopper (BPH) control with less pesticide application. A yeast library expressing 1385 rice transporters was screened, leading to the identification of an amino acid transporter-like (ATL) gene, namely OsATL15, which facilitates THX uptake in both yeast cells and rice seedlings. In contrast to a decrease in THX content in osatl15 knockout mutants, ectopic expression of OsATL15 under the control of the CaMV 35S promoter or a vascular-bundle-specific promoter gdcsPpro significantly increased THX accumulation in rice plants, thus further enhancing the THX efficacy against BPH. OsATL15 was localized in rice cell membrane and abundant in the root transverse sections, vascular bundles of leaf blade, and stem longitudinal sections, but not in hull and brown rice at filling stages. Our study shows that OsATL15 plays an essential role in THX uptake and its systemic distribution in rice. OsATL15 could be valuable in achieving precise pest control by biotechnology approaches.


Assuntos
Hemípteros , Oryza , Praguicidas , Animais , Agroquímicos/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Sistemas de Transporte de Aminoácidos/metabolismo , Hemípteros/genética , Oryza/metabolismo , Praguicidas/metabolismo , Saccharomyces cerevisiae , Tiametoxam/metabolismo
4.
Inorg Chem ; 59(21): 16027-16034, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064476

RESUMO

To estimate the effect of bisphosphine ligands on the formation of the isomeric core structures of gold nanoclusters, the different ligation of bisphosphine ligands is usually used to participate in the construction of gold nanoclusters. Here, the selection of the different bisphosphine ligands, DPEphos and Xantphos, is performed to construct two novel gold nanoclusters, [Au11(DPEphos)4Cl2]Cl (1) and [Au11(Xantphos)4Cl2]Cl(2), which have been characterized by IR, 1H and 31P NMR, ESI-MS, XRD, SEM, XPS, TG, UV-vis, and X-ray crystal structure analysis. The structural analyses indicate that the ligation of bisphosphine ligands play a crucial role in the formation of the fascinating Au11 cores: gold nanocluster 1 includes a birdcage-shaped Au11 core with eight electrons, while gold nanocluster 2 contains a crown-shaped Au11 core with eight electrons. Meanwhile, DOS and PDOS studies indicate that the Au11 cores have a strong effect on the composition of HOMO and LUMO orbitals of gold nanoclusters. Furthermore, the different Au11 core structures lead to different optical absorption characteristics (1: 456 nm; 2: 427 nm). All these demonstrate that the ligation of bisphosphine ligands may have an important influence on constructing the stability of the isomeric core structures of gold nanoclusters.

5.
Dalton Trans ; 48(7): 2455-2466, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30693923

RESUMO

Mn4+-Doped oxide phosphors are under intensive investigation owing to their low manufacture cost and attractive luminescent features for indoor plant cultivation applications. However, it is still a challenge to develop Mn4+-doped oxides with high luminescence efficiency and thermal stability. Herein, Mn4+-Mg2+ pairs are incorporated into a CaGdAlO4 host to reduce non-radiative channels formed by Mn4+-Mn4+-O2- clusters. The photoluminescence and quantum efficiency are significantly enhanced after the introduction of Mg2+ ions to the host. A prolonged Mn4+ decay time is also obtained from the Mn4+/Mg2+ co-doped samples. Intense red emission with a narrow peak at 712 nm due to the 2Eg → 4A2g transition of Mn4+ ions is observed under 335 nm excitation. LEDs fabricated by coating the synthesized phosphor on a 365 nm near-UV chip exhibit an intense deep-red emission with CIE chromaticity coordinates of (0.712, 0.285). The results indicate Mn4+/Mg2+ co-doped CaGdAlO4 phosphors may be applicable to plant cultivation fields.

6.
Dalton Trans ; 40(29): 7551-8, 2011 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-21706081

RESUMO

A series of Cu(I) complexes with a [Cu(NN)(PP)](+) moiety, [Cu(phen)(pba)](BF(4)) (1a), [Cu(2)(phen)(2)(pbaa)](BF(4))(2) (2a), [Cu(2)(phen)(2)(pnaa)](BF(4))(2) (3a), [Cu(2)(phen)(2)(pbbaa)](BF(4))(2) (4a), [Cu(dmp)(pba)](BF(4)) (1b), [Cu(2)(dmp)(2)(pbaa)](BF(4))(2) (2b), [Cu(2)(dmp)(2)(pnaa)](BF(4))(2) (3b) and [Cu(2)(dmp)(2)(pbbaa)](BF(4))(2) (4b) (phen = 1,10-phenanthroline, dmp = 2,9-dimethyl-1,10-phenanthroline, pba = N,N-bis((diphenylphosphino)methyl)benzenamine, pbaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)benzene-1,4-diamine, pnaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)naphthalene-1,5-diamine and pbbaa = N,N,N',N'-tetrakis((diphenylphosphino)methyl)biphenyl-4,4'-diamine), were rationally designed and synthesized. These complexes were characterized by (1)H and (31)P NMR, electrospray mass spectrometry, elemental analysis and X-ray crystal structure analysis. Introduction of different central arene spacers (phenyl, naphthyl, biphenyl) into ligands, resulting in the size variation of these complexes, aims to tune the photophysical properties of the complexes. Each Cu(I) ion in these complexes adopts a distorted tetrahedral geometry constructed by the chelating diimine and phosphine groups. Intermolecular C-H···π and/or π···π interactions are involved in the solid states. The dmp-containing complex exhibits better emission relative to the corresponding phen complex due to the steric encumbrance of bulky alkyl groups. Furthermore, for complexes with identical diimine but different phosphine ligands, the tendency of increased emission lifetime as well as blue-shifted emission in the solid state follows with the decrease in size of complexes. Intermolecular C-H···π interactions have an influence on the final solid state photophysical properties through vibrationally relaxed non-radiative energy transfer in the excited state. Smaller-sized complexes show better photophysical properties due to less vibrationally relaxed behavior related to flexible C-H···π bonds. Nevertheless, the tendency for increased quantum yield and emission lifetime, as well as blue-shifted emission in dilute solution goes with the increase in size of complexes. The central arene ring (phenyl, naphthyl or biphenyl) has an influence on the final photophysical properties. The larger the π-conjugated extension of central arene ring is, the better the photophysical properties of complex are. The rigid and large-sized complex 3b, with a high quantum yield and long lifetime, is the best luminophore among these complexes.

7.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 1): m96, 2010 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-21522609

RESUMO

In the cation of the title compound, [Cu(C(32)H(29)NP(2))(2)]BF(4), the Cu(I) atom is four-coordinated in a distorted tetra-hedral geometry by four P atoms from two N,N-bis-[(diphenyl-phosphan-yl)meth-yl]aniline ligands. In the crystal, the cations are linked by C-H⋯π inter-actions, forming chains along the a axis. Intra-molecular C-H⋯N and inter-molecular C-H⋯F hydrogen bonds are also observed.

8.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 9): m1085, 2009 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21577436

RESUMO

In the centrosymmetric dinuclear title compound, [Cu(2)(C(2)H(3)N)(2)(C(18)H(10)N(4))(2)(C(32)H(30)N(2)P(2))](BF(4))(2), the Cu(I) centre is coordinated by two N atoms from a dipyridophenazine ligand, one P atom from an N,N'-bis-[(diphenyl-phosphan-yl)meth-yl]benzene-1,4-diamine (bpbda) ligand, and one N atom from an acetonitrile mol-ecule in a distorted tetra-hedral geometry. The bpbda ligand, lying on an inversion center, bridges two Cu(I) centres into a Z-shaped complex. Intra-molecular π-π inter-actions between the dipyridophenazine ligand and the benzene ring of the bpbda ligand are observed [centroid-centroid distance = 3.459 (3) Å]. The crystal structure also involves inter-molecular π-π inter-actions between the dipyridophenazine ligands [centroid-centroid distance = 3.506 (3) Å], which lead to a one-dimensional supra-molecular structure.

9.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 6): m634, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-21583002

RESUMO

In the title mononuclear complex, [Mn(C(14)H(10)NO(3))(2)(CH(3)OH)(4)], the Mn(II) atom, lying on an inversion centre, exhibits a distorted octa-hedral geometry, defined by two O atoms from two monodentate ligands and four O atoms from four methanol mol-ecules. The crystal structure involves intra-molecular O-H⋯N and O-H⋯O and inter-molecular O-H⋯O hydrogen bonds.

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