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941.
Recyclable polymeric 1 and dimeric 2 chiral Mn(III) salen complexes catalyzed enantioselective cyanosilylation of various ketones in the presence of triphenylphosphine oxide as an additive proceeded smoothly at room temperature, providing excellent yields (up to 98%) and enantiomeric excess (up to 86%) of respective cyanohydrin trimethylsilyl ether. For most of the substrates, the Catalyst 1 showed slightly better reactivity and enantioselecitivity than the Catalyst 2 nevertheless both the catalysts were easily recovered and reused four times with the retention of their efficiency. 相似文献
942.
Maninder Minu Ananda Thangadurai Sharad Ramesh Wakode Shyam Sundar Agrawal Balasubramanian Narasimhan 《Bioorganic & medicinal chemistry letters》2009,19(11):2960-2964
Antimicrobial activity of synthesized 2,3-disubstituted-3,3a,4,5,6,7-hexahydro-2H-indazole derivatives indicated that 3-(4-chlorophenyl)-2-(4-nitrophenylsulfonyl)-3,3a,4,5,6,7-hexahydro-2H-indazole (6) and 3-(4-fluorophenyl)-2-(4-nitrophenylsulfonyl)-3,3a,4,5,6,7-hexahydro-2H-indazole (20) were the most active compounds. Further, the results of QSAR studies indicated the importance of topological parameters 2χ and 2χv in defining the antimicrobial activity of hexahydroindazoles. 相似文献
943.
B. Kalyana Babu P. K. Agrawal Vinay Mahajan H. S. Gupta 《Journal of plant biochemistry and biotechnology.》2009,18(1):93-96
Fifty microsatellite or simple sequence repeat (SSR) markers, spread across the maize genome were used for analyzing a set of 19 elite Quality Protein Maize (QPM) lines, including seventeen lines developed in India and two at CIMMYT, Mexico. Polymorphic profiles for 47 SSR loci have aided in differentiating the QPM inbred lines. The polymorphism information content (PIC) values among the inbreds ranged from 0.06 (umc2229) to 0.70 (umc1071) with an average of 0.45 per primer-pair. The genetic relationships as indicated by the cluster analysis of SSR data were largely in congruence with the known pedigree of the QPM lines. The study resulted in identification of two SSR markers, umc1071 and umc1063 with higher PIC values of 0.70 and 0.64, respectively. The tryptophan content among the genotypes was found to vary considerably. Two genotypes viz., VOL 2 and VOL 8 were found to differ significantly for tryptophan content (0.51% and 0.94%, respectively). Both these QPM genotypes being derived from the same non-QPM parent CM 145, makes them ideal for mapping of modifiers for tryptophan content. 相似文献
944.
Sagarika Biswas Praveen Agrawal Ashish Saroha Hasi R. Das 《The protein journal》2009,28(9-10):391-399
A glucose specific lectin (STA) was isolated from Sesbania aculeata stem by using Sephadex G-50 affinity column chromatography. The lectin is a glycoprotein having 29 kDa subunit molecular weight. Two dimensional gel electrophoresis analysis revealed that the lectin existed in two isomeric forms with varied carbohydrate content as analyzed by high performance anion exchange chromatography-pulsed amperometric detector (HPAEC-PAD). Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) and N-terminal sequence (LDSLSFTYNNFE) analysis of this lectin showed 95% homology with stem lectin SL-I (accession no. AJ585523) from peanut plant. The nucleotide sequence of the lectin (STA) was submitted to the gene bank (accession no. EU263636). 相似文献
945.
946.
Micropropagation has been achieved in a promising larvicidal asteraceous taxon Spilanthes acmella L. using seedling leaf explants. The explants were reared on a variety of growth regulators, namely 2,4-dichlorophenoxyacetic
acid, 1-naphthalene acetic acid, Indole-3-butyric acid, N6-benzyladenine, and kinetin either alone or in combination on Murashige and Skoog’s (MS) medium. The best green and compact
callus was obtained on 1 μM NAA and 10 μM benzyladenine (BA) in 15 d. The callus on subculture to the same but fresh medium
after every 30 d differentiated an average of 12.90 ± 0.32 shoot buds in 50% cultures. Elongation in shoot buds occurred only
if they were transferred to NAA lacking MS+BA medium. An average number of 4.22 ± 0.83 shoots and 15 ± 0.84 shoot buds per
explant were obtained in 70.3% cultures on MS + 10 μM BA in 30 d. One hundred percent excised shoots rooted in MS(1/2) + 0.1 μM
IBA within 2 wk. The plants were gradually hardened and established in soil where they flowered and set viable seeds. The
regenerated plants were morphologically similar to the field grown plants and showed 100% larvicidal activity against malaria
and filarial vectors. 相似文献
947.
Shubha Shukla Rajnish Kumar Chaturvedi Kavita Seth Neeta Singh Roy§ Ashok Kumar Agrawal 《Journal of neurochemistry》2009,109(2):436-451
Transplantation of neural stem cell (NSC)-derived dopamine (DA) neurons is associated with low survival of cells, which could be due to limited striatal innervations and uneven distribution of graft because of its dense neuronal core, limited host–graft interaction, poor axonal outgrowth, lack of continuous neurotrophic factors supply, and an absence of cell adhesion molecules mediated appropriate developmental cues. Olfactory ensheathing cells (OEC) express a variety of growth factors and cell adhesion molecules and promote axonal regrowth and functional recovery in spinal cord injury in animal models and patients. In the present study, we explored the possibility to increase the survival, function, axonal outgrowth and striatal reinnervation of NSC by co-grafting with OEC in 6-OHDA lesioned parkinsonian rats. In the presence of OEC, significantly enhanced survival of NSC-derived DA neurons and axonal fiber outgrowth was evident in the striatum of NSC+OEC co-grafted rats at 24 weeks post-grafting as compared with NSC alone grafted rats. The increased survival of NSC and their striatal reinnervation was further manifested in the form of significant and substantial restitution of motor function and neurochemical recovery in the co-grafted group. Significant enhanced expression of p75NTR (from OEC) and tyrosine hydroxylase (TH) (from NSC) confirmed the co-localization and survival of both types of cells at the transplantation site in co-grafted rats. Co-grafting results co-related well with our in vitro studies, which suggest that OEC not only significantly increase survival, neurite outgrowth and DA release of NSC-derived DA neuron but also protect against 6-OHDA neurotoxicity in co-culture conditions. These results collectively suggest that OEC increase the survival and function of transplanted NSC in 6-OHDA lesioned parkinsonian rats. 相似文献
948.
Swati Agrawal Giel G. van Dooren Wandy L. Beatty Boris Striepen 《The Journal of biological chemistry》2009,284(48):33683-33691
Most apicomplexan parasites harbor a relict chloroplast, the apicoplast, that is critical for their survival. Whereas the apicoplast maintains a small genome, the bulk of its proteins are nuclear encoded and imported into the organelle. Several models have been proposed to explain how proteins might cross the four membranes that surround the apicoplast; however, experimental data discriminating these models are largely missing. Here we present genetic evidence that apicoplast protein import depends on elements derived from the ER-associated protein degradation (ERAD) system of the endosymbiont. We identified two sets of ERAD components in Toxoplasma gondii, one associated with the ER and cytoplasm and one localized to the membranes of the apicoplast. We engineered a conditional null mutant in apicoplast Der1, the putative pore of the apicoplast ERAD complex, and found that loss of Der1Ap results in loss of apicoplast protein import and subsequent death of the parasite. 相似文献
949.
An attempt has been made to determine if drought-induced proteins could be used as a selection marker to differentiate between
tolerant and sensitive cultivars. Three Indian tomato (Lycopersicon esculentum Mill.) cultivars (Pusa Ruby, Arka Vikas and Pusa Early Dwarf) were subjected to drought stress in vivo as well as in vitro and the pattern of polypeptide expression was determined using one-dimensional SDS-PAGE. In all the three cultivars, a new
29 kDa polypeptide accumulated in leaves, in response to gradual drought stress and its accumulation was fastest in Pusa Ruby.
Drought stress also resulted in an increase in ion leakage from leaf discs of all the three cultivars but the rate was lower
in Pusa Ruby than in other two. Therefore, it was concluded that Pusa Ruby is most tolerant to drought stress among the three
tomato cultivars investigated. 相似文献
950.
Pathak M Singh B Sharma A Agrawal P Pasha SB Das HR Das RH 《Plant molecular biology》2006,62(4-5):529-545
Isolation and purification of a α-methyl-mannoside specific lectin (SL-I) of peanut was reported earlier [Singh and Das (1994) Glycoconj J 11:282–285]. Native SL-I is a glycoprotein having ∼31 kDa subunit molecular mass and forms dimer. The gene encoding this lectin is identified from a 6-day old peanut root cDNA library by anti-SL-I antibody and N-terminal amino acid sequence homology to the native lectin. Nucleotide sequence derived amino acid sequence of the re-SL-I shows amino acid sequence homology with the N-terminal and tryptic digests’ amino acid sequence of the native SL-I (nSL-I). Presence of a putative glycosylation (QNPS) site and a hydrophobic adenine-binding (VLVSYDANS) site is also identified in SL-I. Homology modeling of the lectin suggests it to be an archetype of legume lectins. It is expressed as a ~30 kDa apoprotein in E. coli and has the carbohydrate specificity and secondary structure identical to its natural counterpart. The lectin SL-I inhibits cytokinin 6-benzylaminopurine (BA)-induced “delayed leaf senescence” and “cotyledon expansion”. Equilibrium dialysis revealed a single high-affinity binding site for adenine (7.6 × 10−6 M) and BA (1.09 × 10−5 M) in the SL-I dimer and thus suggesting that the cytokinin antagonist effect of SL-I is mediated by the direct interaction of SL-I with BA.The nucleotide sequence data reported here are available in the DDBJ/EMBL/GenBank databases under the Accession No. AJ585523 相似文献