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71.
Dehydrins (DHNs) compose a family of intrinsically unstructured proteins that have high water solubility and accumulate during late seed development at low temperature or in water-deficit conditions. They are believed to play a protective role in freezing and drought-tolerance in plants. A full-length cDNA encoding DHN (designated as ClDhn) was isolated from an oriental medicinal plant Codonopsis lanceolata, which has been used widely in Asia for its anticancer and anti-inflammatory properties. The full-length cDNA of ClDhn was 813 bp and contained a 477 bp open reading frame (ORF) encoding a polypeptide of 159 amino acids. Deduced ClDhn protein had high similarities with other plant DHNs. RT-PCR analysis showed that different abiotic stresses such as salt, wounding, chilling and light, triggered a significant induction of ClDhn at different time points within 4-48 hrs post-treatment. This study revealed that ClDhn assisted C. lanceolata in becoming resistant to dehydration. 相似文献
72.
Manoj Manickam Pulla Reddy Boggu Thanigaimalai Pillaiyar Niti Sharma Hitesh B. Jalani Eeda Venkateswararao Sang-Hun Jung 《Bioorganic & medicinal chemistry letters》2018,28(14):2369-2374
To explore novel cardiac myosin activator, a series of diphenylalkyl substituted 1,3,4-oxadiazoles and 1,2,4-oxadiazoles have been prepared and tested for cardiac myosin ATPase activation in vitro. In all cases, three carbon spacer between the oxadiazole core and one of the phenyl ring was considered crucial. In case of 1,3,4-oxadiazole, zero to two carbon spacer between oxadiazole core and other phenyl ring are favorable. Phenyl ring can be replaced by cyclohexyl moiety. In case of 1,2,4-oxadiazole, zero or one carbon spacer between the oxadiazole and other phenyl ring are favorable. Introduction of hydrogen bonding donor (NH) group at the 2nd position of the 1,3,4-oxadiazole enhances the activity. Substitutions on either of the phenyl rings or change of phenyl ring to other heterocycle are not tolerated for both the oxadiazoles. The prepared oxadiazoles showed selective activation for cardiac muscle over smooth and skeleton muscles. 相似文献
73.
Manoj Manickam Pulla Reddy Boggu Jungsuk Cho Yeo Jin Nam Seung Jin Lee Sang-Hun Jung 《Bioorganic & medicinal chemistry letters》2018,28(11):2023-2028
To establish the structure-activity relationship of 5-hydroxy-1,4-naphthoquinones toward anticancer activity, a series of its derivatives were prepared and tested for the activity (IC50 in µM) against three cell lines; colo205 (colon adenocarcinoma), T47D (breast ductal carcinoma) and K562 (chronic myelogenous leukemia). Among them 2 (IC50: 2.3; 2.0; 1.4?µM), 6 (IC50: 1.9; 2.2; 1.3?µM), 9 (IC50: 0.7; 1.7; 0.9?µM) and 10 (IC50:1.7; 1.0; 1.2?µM) showed moderate to excellent activity. Our perception toward the DNA substitution of alkoxy groups at the C2 position of these naphthoquinones for the anticancer activity led us to investigate their reactivity of substitution toward dimethylamine as a nucleophile. The ease of the substitution of alkoxy groups at the C2 position with dimethylamine is strongly accelerated by hydroxyl group at C5 position and is well correlated with the found anticancer activity results. 相似文献
74.
Iwano M Shiba H Matoba K Miwa T Funato M Entani T Nakayama P Shimosato H Takaoka A Isogai A Takayama S 《Plant physiology》2007,144(1):72-81
The self-incompatibility system of the plant species Brassica is controlled by the S-locus, which contains S-RECEPTOR KINASE (SRK) and S-LOCUS PROTEIN11 (SP11). SP11 binding to SRK induces SRK autophosphorylation and initiates a signaling cascade leading to the rejection of self pollen. However, the mechanism controlling hydration and germination arrest during self-pollination is unclear. In this study, we examined the role of actin, a key cytoskeletal component regulating the transport system for hydration and germination in the papilla cell during pollination. Using rhodamine-phalloidin staining, we showed that cross-pollination induced actin polymerization, whereas self-pollination induced actin reorganization and likely depolymerization. By monitoring transiently expressed green fluorescent protein fused to the actin-binding domain of mouse talin, we observed the concentration of actin bundles at the cross-pollen attachment site and actin reorganization and likely depolymerization at the self-pollen attachment site; the results correspond to those obtained by rhodamine-phalloidin staining. We further showed that the coat of self pollen is sufficient to mediate this response. The actin-depolymerizing drug cytochalasin D significantly inhibited pollen hydration and germination during cross-pollination, further emphasizing a role for actin in these processes. Additionally, three-dimensional electron microscopic tomography revealed the close association of the actin cytoskeleton with an apical vacuole network. Self-pollination disrupted the vacuole network, whereas cross-pollination led to vacuolar rearrangements toward the site of pollen attachment. Taken together, our data suggest that self- and cross-pollination differentially affect the dynamics of the actin cytoskeleton, leading to changes in vacuolar structure associated with hydration and germination. 相似文献
75.
Kaothien P Ok SH Shuai B Wengier D Cotter R Kelley D Kiriakopolos S Muschietti J McCormick S 《The Plant journal : for cell and molecular biology》2005,42(4):492-503
The pollen-specific receptor kinases LePRK1 and LePRK2 have localization and expression profiles that strongly suggest they play roles in pollen germination and tube growth. To identify downstream components of LePRK signaling, we used their cytoplasmic domains (CDs) as baits in yeast two-hybrid screens of a tomato pollen cDNA library. A pollen-specific protein we named kinase partner protein (KPP) interacted with the CDs of both LePRK1 and LePRK2 in yeast and in an in vitro pull-down assay, and with LePRK2 in a co-immunoprecipitation assay. KPP is a peripheral membrane protein and is phosphorylated in pollen. Pollen tubes over-expressing KPP developed balloon-like tips with abnormal cytoplasmic streaming and F-actin arrangements and plants over-expressing KPP exhibited impaired transmission of the transgene through the male. KPP-like genes are found only in plants; the 14 family members in Arabidopsis thaliana exhibit diverse expression patterns and potentially play roles in signaling pathways in other tissues. 相似文献
76.
Cloning, expression, purification, and characterization of the acid alpha-mannosidase from Trypanosoma cruzi 总被引:1,自引:0,他引:1
Vandersall-Nairn AS; Merkle RK; O'Brien K; Oeltmann TN; Moremen KW 《Glycobiology》1998,8(12):1183-1194
The acid alpha-mannosidase of Trypanosoma cruzi is a broad-specificity
hydrolase involved in the catabolism of glycoconjugates, presumably in the
digestive vacuole. We have cloned the alpha-mannosidase gene from a T.cruzi
epimastigote genomic library. The alpha-mannosidase gene was determined to
be single copy by Southern analysis, and similar sequences were not
detected in genomic digests of either Trypanosoma brucei or Leishmania
donovani. The coding region was subcloned into the Pichia pastoris
expression vector pPICZ, and alpha-mannosidase activity was detected in the
medium of induced cultures. The recombinant alpha- mannosidase demonstrated
a pH optimum, inhibition by swainsonine, Km, and substrate specificity
consistent with the characteristics of the alpha-mannosidase previously
purified from T.cruzi epimastigotes. The recombinant enzyme was purified
103-fold from the culture medium of Pichia pastoris and had a native
molecular mass of 359 kDa by gel filtration. A combination of SDS-PAGE,
deglycosylation with endo H, and NH2-terminal sequencing indicates that the
enzyme is originally synthesized as a homodimeric polypeptide that is
subsequently cleaved to form a heterotetramer composed of 57 and 46 kDa
subunits. A polyclonal antibody raised to the recombinant enzyme was shown
to immunoprecipitate the alpha-mannosidase from T.cruzi cell extracts and
will be used in future immunolocalization studies.
相似文献
77.
Green synthesis method is being increasingly used in the development of safe, stable, and eco-friendly nanostructures with biological resources. In this study, extracellular and intracellular synthesis of gold nanoparticles (AuNPs) was carried out using green algae Chlorella sorokiniana Shihira & R.W. Fresh algae were isolated and identified from Musaözü Pond located in the province of Eskişehir and then extraction process were performed. Optimization studies were studied using pH value, metal salt concentration, and time parameters for extracellular synthesis and using only time parameter for intrasellular synthesis. Since more controlled and optimum conditions can be achieved in the production of AuNPs by extracellular synthesis, these nanoparticles (NPs) were used for characterization and antifungal activity studies. Optical, physical, and chemical properties of synthesized NPs were characterized by UV visible spectrophotometer (UV-Vis), dynamic light scattering (DLS), Zetasizer, X-Ray diffraction (XRD), Fourier transform ınfrared spectroscopy (FTIR), field emission scanning electron microscope (FE-SEM), ınductively coupled plasma mass spectrometer (ICP-MS) and transmission electron microscope (TEM) analysis. The optimum conditions for AuNPs synthesis were determined as 1 mM for HauCl4 concentration, 6 for pH value, and 60th min for time. AuNPs obtained from extracellular synthesis from C. sorokiniana extract are 5–15 nm in size and spherical shape. TEM images of extracellular synthesis show noticeable cell wall and membrane damages, cytoplasma dissolutions, and irregularities. AuNPs obtained by intracellular synthesis are in 20–40 nm size and localized in the cell wall and cytoplasm. These NPs exhibited significant antifungal activity against C. tropicalis, C. glabrata, and C. albicans isolates. AuNPs obtained by algae-mediated green synthesis have a significant potential for medical and industrial use, and this eco-friendly synthesis method can be easily scaled for future studies. 相似文献
78.
Rama Krishna Pulla Ok Ran Lee Jun-Gyo In Shohana Parvin Yu-Jin Kim Ju-Sun Shim Hua Sun Yeon-Ju Kim Kalaiselvi Senthil Deok-Chun Yang 《Molecular biology reports》2011,38(1):95-102
The role of plant chitinases in protecting plants against a variety of fungal pathogens is well established. In the present
study, a cDNA clone containing a class I chitinase (Chi-1) gene, designated as PgChi-1, has been isolated from the oriental medicinal plant Panax ginseng. PgChi-1 is predicted to encode a protein of 34.9 kDa consisting of 323 amino acid residues. PgChi-1 was found to be expressed constitutively in all of the studied organs of ginseng plant. Under various abiotic stress treatments
including Cu, H2O2, mannitol, SA, JA, and NaCl, the expression of PgChi-1 in plantlets and hairy roots increased significantly compared to the control. When different parts of root were analyzed,
maximum level was observed in taproot. In addition, levels of PgChi-1 expression were compared between healthy root and fungal, bacterial, and nematode infected root. Significant increase of
PgChi-1 was noticed in pathogen infected roots than healthy roots. This study revealed that PgChi-1 may protect the P. ginseng under both biotic and abiotic stress conditions. 相似文献
79.
Fe(III)-saccharide complexes of d-glucose and d-fructose have been synthesized from methanol using stoichiometric quantities of sodium salts of the corresponding saccharides. Both the compounds were isolated in the solid state and characterized by various analytical, spectroscopic, magnetic and cyclic voltammetric methods. Both the complexes were found to be stable, in solution, in the pH range 2.5–12.0.This paper is dedicated to Professor Richard H. Holm on his 60th birthday. 相似文献
80.
HÜSEYIN SÜMBÜL R. SÜLEYMAN GÖKTÜRK OLCAY DNÇ DÜEN 《Botanical journal of the Linnean Society. Linnean Society of London》2003,141(2):251-254
A new species of Helichrysum Gaertn., H. orbicularifolium Sümbül, R. S. Göktürk & O. D. Düşen sp. nov. , is described and illustrated. The species is restricted to the south Anatolia Province, Antalya, Turkey, growing in humid calcareous rock crevices and on limestone cliffs. The species is compared with the closely related H. chasmolycicum . © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 251–254. 相似文献