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排序方式: 共有388条查询结果,搜索用时 15 毫秒
1.
Eliahu Heldman Ayala Balan Ora Horowitz Sarit Ben-Zion Michael Torten 《FEBS letters》1985,180(2):243-248
Antiparaoxon immune sera were employed in a new immunoassay based on competition between acetylcholinesterase and antibodies for the binding ofparaoxon. Unlike radioimmunoassay, the new assay described herein can be extended to predict the feasibility of antibodies to confer in vivo protection of acetylcholinesterase against organophosphate poisoning. The toxicity of paraoxon was reduced in mice which were pre-injected with the immune sera. 相似文献
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Two target polypeptides were detected by photoaffinity labelling of purified mung bean mitochondria using tritiated 2-azido-N6-benzylaminopurine. SDS-PAGE and fluorography of total mitochondrial proteins after the photoaffinity reaction showed a labelled 32 kDa polypeptide (intensely labelled) and a 57 kDa polypeptide (less intensely labelled). The latter was assumed to be the and/or subunit of F1ATPase since it was the most abundant polpeptide in gels stained with Coomassie Blue. Partial purification of F1ATPase demonstrated that the 32 kDa polypeptide was not a component of the ATPase complex. Fractionation experiments showed that the 32 kDa protein was integrally associated with mitochondrial membranes and could be enriched by simple washing and detergent extraction procedures. 相似文献
4.
Spatial distribution of root activity and nitrogen fixation in sorghum/pigeonpea intercropping on an Indian Alfisol 总被引:2,自引:0,他引:2
Ito Osamu Matsunaga Ryoichi Tobita Satoshi Rao Theertham P. Devi Y. Gayatri 《Plant and Soil》1993,155(1):341-344
A medium-duration pigeonpea cultivar (ICP 1–6) and a hybrid sorghum (CSH 5) were grown on a shallow Alfisol in monocropping and intercropping systems. Using a monolith method, spatial distribution of nodulation, acetylene reduction activity (ARA) and root respiration were measured.The number, mass and ARA of nodules decreased exponentially with distance from the plant base except at the late reproductive stage. Nodulation and ARA tended to be higher in the intercrop than in the monocrop.Respiration rate of roots increased with distance from the plant base and reached a maximum value at about 20–30 cm. The rate was higher in pigeonpea than in sorghum and also higher in intercrop than in monocrop.This study suggests that pigeonpea roots are physiologically more active than sorghum roots, implying that pigeonpea may become a strong competitor for nutrients in the soil when intercropped. The nitrogen-fixing ability of pigeonpea may be enhanced by intercropping because the sorghum rapidly absorbed inorganic N which would otherwise inhibit N2 fixation. 相似文献
5.
Leon V. Backinowsky Nikolay F. Balan Vitali I. Betaneli Nikolay K. Kochetkov 《Carbohydrate research》1982,99(2):189-193
The capsular polysaccharide from Klebsiella type K54, containing both O-formyl and O-acetyl groups, has been investigated by using the techniques of methylation analysis (by gas-liquid chromatography), periodate oxidation-Smith degradation, and both 1H- and 13C-n.m.r. spectroscopy. Degradation of the native polysaccharide with a bacteriophage-induced glucosidase generated a formylated, as well as a formylated and acetylated, tetrasaccharide, whereas similar depolymerization of the deacetylated polysaccharide yielded a single tetrasaccharide; the corresponding, O-acylated octasaccharides were also isolated and characterized. These oligosaccharides, utilized in chemical and spectroscopic studies in order to determine the location of the O-acyl substituents in the repeating sequence, indicated formylation at O-4 of each lateral d-glucosyl group and acetylation at O-2 of alternate l-fucosyl residues. A new structure for the repeating unit in the polysaccharide is proposed. 相似文献
6.
Kumar Ritesh Khungar Lisha Shimphrui Rinchuila Tiwari Lalit Dev Tripathi Gayatri Sarkar Neelam K. Agarwal Surekha-Katiyar Agarwal Manu Grover Anil 《Journal of plant biochemistry and biotechnology.》2020,29(4):715-732
Journal of Plant Biochemistry and Biotechnology - Caseinolytic protease (Clp)/Hsp100 proteins are members of the AAA+ (ATPase associated with a variety of cellular activities) family of proteins... 相似文献
7.
Balan Biji Dhaulaniya Amit S. Varma Diksha A. Sodhi Kushneet K. Kumar Mohit Tiwari Manisha Singh Dileep Kumar 《Archives of microbiology》2021,203(1):13-30
Archives of Microbiology - Biofilms are structured microbial communities of single or multiple populations in which microbial cells adhere to a surface and get embedded in extracellular polymeric... 相似文献
8.
Gayatri Jayaraman Karikalan Sinha Subodh Kumar Roy Pranita Mandal Pranab Kumar 《Plant Molecular Biology Reporter》2021,39(3):520-545
Plant Molecular Biology Reporter - Polyploidization plays an important role in the genesis of cultivated wheat (hexaploid and tetraploid) from its diploid progenitors. Thus, evolution during... 相似文献
9.
Samantha J. Emery-Corbin Joshua J. Hamey Balu Balan Laura Rojas-López Staffan G. Svärd Aaron R. Jex 《International journal for parasitology》2021,51(4):225-239
Diarrheal disease caused by Giardia duodenalis is highly prevalent, causing over 200 million cases globally each year. The processes that drive parasite virulence, host immune evasion and transmission involve coordinated gene expression and have been linked to epigenetic regulation. Epigenetic regulatory systems are eukaryote-conserved, including in deep branching excavates such as Giardia, with several studies already implicating histone post-translational modifications in regulation of its pathogenesis and life cycle. However, further insights into Giardia chromatin dynamics have been hindered by a lack of site-specific knowledge of histone modifications. Using mass spectrometry, we have provided the first known molecular map of histone methylation, acetylation and phosphorylation modifications in Giardia core histones. We have identified over 50 previously unreported histone modifications including sites with established roles in epigenetic regulation, and co-occurring modifications indicative of post-translational modification crosstalk. These demonstrate conserved histone modifications in Giardia which are equivalent to many other eukaryotes, and suggest that similar epigenetic mechanisms are in place in this parasite. Further, we used sequence, domain and structural homology to annotate putative histone enzyme networks in Giardia, highlighting representative chromatin modifiers which appear sufficient for identified sites, particularly those from H3 and H4 variants. This study is to our knowledge the first and most comprehensive, complete and accurate view of Giardia histone post-translational modifications to date, and a substantial step towards understanding their associations in parasite development and virulence. 相似文献
10.
Aline Sampaio Cremonesi Lilia I. De la Torre Maximillia Frazão de Souza Gabriel S. Vignoli Muniz M. Teresa Lamy Cristiano Luis Pinto Oliveira Andrea Balan 《Biochemistry and Biophysics Reports》2021
ATP-Binding Cassette transporters (ABC transporters) are protein complexes involved in the import and export of different molecules, including ions, sugars, peptides, drugs, and others. Due to the diversity of substrates, they have large relevance in physiological processes such as virulence, pathogenesis, and antimicrobial resistance. In Xanthomonas citri subsp. citri, the phytopathogen responsible for the citrus canker disease, 20% of ABC transporters components are expressed under infection conditions, including the putative putrescine/polyamine ABC transporter, PotFGHI. Polyamines are ubiquitous molecules that mediate cell growth and proliferation and play important role in bacterial infections. In this work, we characterized the X. citri periplasmic-binding protein PotF (XAC2476) using bioinformatics, biophysical and structural methods. PotF is highly conserved in Xanthomonas sp. genus, and we showed it is part of a set of proteins related to the import and assimilation of polyamines in X. citri. The interaction of PotF with putrescine and spermidine was direct and indirectly shown through fluorescence spectroscopy analyses, and experiments of circular dichroism (CD) and small-angle X-ray scattering (SAXS), respectively. The protein showed higher affinity for spermidine than putrescine, but both ligands induced structural changes that coincided with the closing of the domains and increasing of thermal stability. 相似文献