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101.
Harish Rajak Bhupendra Singh Thakur Avineesh Singh Kamlesh Raghuvanshi Anil Kumar Sah Ravichandran Veerasamy Prabodh Chander Sharma Rajesh Singh Pawar Murli Dhar Kharya 《Bioorganic & medicinal chemistry letters》2013,23(3):864-868
Two novel series of N4-(5-(2/3/4-substituted-phenyl)-1,3,4-oxadiazol-2-yl)-N1-(2-methyl-5-(prop-1-en-2-yl)cyclohex-2-enylidene)semicarbazide and N4-(5-(2/3/4-substituted-phenyl)-1,3,4-oxadiazol-2-yl)-N1-(3,7-dimethylocta-3,6-dienylidene)-semicarbazide were synthesized to meet structural prerequisite indispensable for anticonvulsant activity. The anticonvulsant activities of the compounds were investigated using maximal electroshock seizure (MES), subcutaneous pentylenetrtrazole (scPTZ) and subcutaneous strychnine (scSTY) models. The rotorod test was conducted to evaluate neurotoxicity. Some of the selected active compounds were subjected to GABA assay to confirm their mode of action. The outcome of the present investigations proved that the four binding sites pharmacophore model is vital for anticonvulsant activity. The efforts were also made to establish structure–activity relationships among test compounds. 相似文献
102.
Effect of Mineral Phosphate Solubilization on Biological Nitrogen Fixation by Diazotrophic Cyanobacteria 总被引:4,自引:0,他引:4
The ability of two diazotrophic cyanobacteria Westiellopsis prolifica and Anabaena variabilis were examined to solubilize extracellular insoluble tricalcium phosphate (TCP) and Mussorie rock phosphate (MRP). The two
strains exhibited a differential response to insoluble forms of phosphorus used. W. prolifica showed better growth in presence of MRP while A. variabilis proliferated better in presence of TCP. Biological nitrogen fixation measured in terms of acetylene reduction (AR) activity
showed significant variation among the concentrations of TCP or MRP and time of incubation. W. prolifica and A. variabilis showed maximum AR activity on 14 and 21 days of incubation respectively. In general AR activity in presence of MRP was always
less than that in presence of TCP at all concentrations. Among the two cyanobacteria A. variabilis was best in terms of P-solubilization and nitrogen fixation and TCP (20 mg P l−1) was the best source of insoluble P rather than MRP or K2HPO4. 相似文献
103.
Female goldeneyed lacewings (Neuroptera: Chrysopidae) approach but seldom enter traps baited with the male-produced compound iridodial 总被引:1,自引:0,他引:1
Earlier, we identified (1R,2S,5R,8R)-iridodial as a male-specific compound of the goldeneyed lacewing, Chrysopa oculata Say (Neuroptera: Chrysopidae), but traps baited with this compound caught almost exclusively males. In the present report, we demonstrated by sweep-net sampling and observation in the vicinity of pheromone lures that C. oculata females, and males, are strongly attracted to iridodial. Aggregation activity of C. oculata adults occurred between dusk and dawn. This research demonstrates that iridodial may be useful to induce goldeneyed lacewings to lay eggs in targeted plant patches for biological pest control. 相似文献
104.
105.
Martins C Gunaratnam M Stuart J Makwana V Greciano O Reszka AP Kelland LR Neidle S 《Bioorganic & medicinal chemistry letters》2007,17(8):2293-2298
The design, synthesis, biophysical and biochemical evaluation is presented of a new series of benzylamino-substituted acridines as G-quadruplex binding telomerase inhibitors. Replacement of the previously reported anilino substituents by benzylamino groups results in enhanced quadruplex interaction, and for one compound, superior telomerase inhibitory activity. 相似文献
106.
The effect of cosolvents on the fluorescence of solutes was measured manually and in an automated high-performance liquid chromatography (HPLC) system that eliminates fluorescent contaminants on-line. The HPLC system was used to show that the effect of cosolvents on the fluorescence spectrum of heated chymotrypsin (a measure of unfolding) correlates with the effect of the solutes on the heat stabilization of catalytic activity; r2=0.73 with 12 example cosolvents. Changes in the fluorescence of model probes showed that known counteracting solutes slightly decrease the polarity of the solvent. Different cosolvents affect the proton transfer indicator, 2-naphthol (a model for tyrosinyl residues) differently, polyhydric alcohols enhance the protonated naphthol emission whereas zwitterionic solutes enhance naphthoxide fluorescence. The results with the automated system are consistent with the known stabilizing effects of the cosolvents and validate it as a tool to explore the development of novel cosolvents and their effects on multiple biological systems. 相似文献
107.
Rajapandian Kanagaraj Miguel B. Araujo Rathin Barman Priya Davidar Rahul De Dinesh K. Digal G. V. Gopi A. J. T. Johnsingh Kashmira Kakati Stephanie Kramer‐Schadt Babu R. Lamichhane Salvador Lyngdoh M. D. Madhusudan Muneer Ul Islam Najar Jyotirmayee Parida Narendra M. B. Pradhan Jean‐Philippe Puyravaud R. Raghunath P. P. Abdul Rahim K. Muthamizh Selvan Naresh Subedi Antonio Trabucco Swati Udayraj Thorsten Wiegand Amirtharaj C. Williams Surendra P. Goyal 《Diversity & distributions》2019,25(5):822-838
108.
109.
Madhusudan Dey Brian Rick Mann Ashish Anshu M. Amin-ul Mannan 《The Journal of biological chemistry》2014,289(9):5747-5757
Protein kinase R (PKR) functions in a plethora of cellular processes, including viral and cellular stress responses, by phosphorylating the translation initiation factor eIF2α. The minimum requirements for PKR function are homodimerization of its kinase and RNA-binding domains, and autophosphorylation at the residue Thr-446 in a flexible loop called the activation loop. We investigated the interdependence between dimerization and Thr-446 autophosphorylation using the yeast Saccharomyces cerevisiae model system. We showed that an engineered PKR that bypassed the need for Thr-446 autophosphorylation (PKRT446∼P-bypass mutant) could function without a key residue (Asp-266 or Tyr-323) that is essential for PKR dimerization, suggesting that dimerization precedes and stimulates activation loop autophosphorylation. We also showed that the PKRT446∼P-bypass mutant was able to phosphorylate eIF2α even without its RNA-binding domains. These two significant findings reveal that PKR dimerization and activation loop autophosphorylation are mutually exclusive yet interdependent processes. Also, we provide evidence that Thr-446 autophosphorylation during PKR activation occurs in a cis mechanism following dimerization. 相似文献
110.
Chanda Sinha Anuradha Nischal Kamlesh K Pant Srinivas Bandaru Anuraj Nayarisseri Sanjay Khattri 《Bioinformation》2014,10(10):611-616
The HIV-1 protein Vif is essential for in vivo viral replication that targets the human DNA-editing enzyme, APOBEC3G (A3G),
which inhibits replication of retroviruses. The Vif-A3G interactions are believed to be important targets for antiviral drug
development. Since the interactions of A3G and Vif evade the ubiquitination pathways in human host, the viral replication
precedes which otherwise spreads infection. In this study, two potent Vif inhibitors RN 18 and VEC5 have been evaluated for their
inhibitory potential employing ligand receptor and protein-protein interactions studies. VEC 5 showed better interaction with Vif
than RN18. Predicted data show that VEC5 bound Vif and RN18 bound Vif showed diminished interaction to A3G compared to
inhibitor unbound Vif. However, this should be further validated using in vitro studies. 相似文献