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The study was conducted to standardize a protocol for Agrobacterium-mediated genetic transformation of buffel grass (Cenchrus ciliaris L.). Embryogenic calli, produced from one-year-old mature seeds of buffel grass, were used as target cells for Agrobacterium-mediated transformation. A. tumefaciens strain LBA4404, harbouring pCAMBIA-1301 or pCAMBIA-2301, was used for co-cultivation with embryogenic calli from three genotypes (IG-3108, IG-9757 and IG-97101). Co-culturing of calli with Agrobacterium for 30 minutes, followed by co-cultivation with 0.1 mM acetosyringone for 3 days was found to be optimum for maximum transformation efficiency. Presence of acetosyringone during co-cultivation was found to be necessary for transformation. Transient GUS (beta-glucuronidase) gene expression was used to monitor T-DNA delivery into the target cells. Significant genotypic variations in response to transformation were observed among the tested genotypes. A very high frequency (63.3%) of GUS gene expression was obtained following Agrobacterium-mediated gene transfer into embryogenic calli. The standardized protocol would be useful for Agrobacterium-mediated genetic transformation of buffel grass with genes of agronomic importance. 相似文献
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Ranjeet R. Kumar Suneha Goswami Mohammad Shamim Kavita Dubey Khushboo Singh Shweta Singh Yugal K. Kala Ravi R.K. Niraj Akshay Sakhrey Gyanendra P. Singh Monendra Grover Bhupinder Singh Gyanendra K. Rai Anil K. Rai Viswanathan Chinnusamy Shelly Praveen 《Functional & integrative genomics》2017,17(6):621-640
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Mohana Kumara P Zuehlke S Priti V Ramesha BT Shweta S Ravikanth G Vasudeva R Santhoshkumar TR Spiteller M Uma Shaanker R 《Antonie van Leeuwenhoek》2012,101(2):323-329
Rohitukine is a chromane alkaloid possessing anti-inflammatory, anti-cancer and immuno-modulatory properties. The compound
was first reported from Amoora rohituka (Meliaceae) and later from Dysoxylum binectariferum (Meliaceae) and Schumanniophyton problematicum (Rubiaceae). Flavopiridol, a semi-synthetic derivative of rohitukine is a potent CDK inhibitor and is currently in Phase
III clinical trials. In this study, the isolation of an endophytic fungus, Fusarium proliferatum (MTCC 9690) from the inner bark tissue of Dysoxylum binectariferum Hook.f (Meliaceae) is reported. The endophytic fungus produces rohitukine when cultured in shake flasks containing potato
dextrose broth. The yield of rohitukine was 186 μg/100 g dry mycelial weight, substantially lower than that produced by the
host tissue. The compound from the fungus was authenticated by comparing the LC–HRMS and LC–HRMS/MS spectra with those of
the reference standard and that produced by the host plant. Methanolic extract of the fungus was cytotoxic against HCT-116
and MCF-7 human cancer cell lines (IC50 = 10 μg/ml for both cancer cell lines). 相似文献
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Singh AR Joshi S Arya R Kayastha AM Srivastava KK Tripathi LM Saxena JK 《Parasitology international》2008,57(3):354-361
5' EST from filarial gene database has been subjected to 3' rapid amplification of cDNA ends (RACE), semi-nested PCR and PCR to obtain full-length cDNA of Brugia malayi. Full-length hexokinase gene was obtained from cDNA using gene specific primers. The elicited PCR product was cloned, sequenced and expressed as an active enzyme in Escherichia coli. Sequence analysis of B. malayi hexokinase (BmHk) revealed 59% identity with nematode Caenorhabditis elegans but low similarity with all other available hexokinases including human. BmHk, an apparent tetramer with subunit molecular mass of 72 kDa, was able to phosphorylate glucose, fructose, mannose, maltose and galactose. The Km values for glucose, fructose and ATP were found to be 0.035+/-0.005, 75+/-0.3 and 1.09+/-0.5 mM respectively. BmHk was strongly inhibited by ADP, glucosamine, N-acetyl glucosamine and mannoheptulose. The recombinant enzyme was found to be activated by glucose-6-phosphate. ADP exhibited noncompetitive inhibition with the substrate glucose (Ki=0.55 mM) while, mixed type of inhibition was observed with inorganic pyrophosphate (PPi) when ATP was used as substrate (Ki=9.92 microM). The enzyme activity is highly dependent on maintenance of free sulfhydryl groups. CD analysis indicated that BmHk is composed of 37% alpha-helices and 26% beta-sheets. The observed differences in kinetic properties of BmHk as compared to host enzyme may facilitate designing of specific inhibitors against BmHk. 相似文献
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Rashi Verma Monika Yadav Rajabrata Bhuyan Shweta Aggarwal Arnab Nayek 《Journal of receptor and signal transduction research》2016,36(6):601-616
Computer-aided antibody engineering has been successful in the design of new biologics for disease diagnosis and therapeutic interventions. Interleukin-6 (IL-6), a well-recognized drug target for various autoimmune and inflammatory diseases such as rheumatoid arthritis, multiple sclerosis, and psoriasis, was investigated in silico to design potential lead antibodies. Here, crystal structure of IL-6 along with monoclonal antibody olokizumab was explored to predict antigen–antibody (Ag???Ab)-interacting residues using DiscoTope, Paratome, and PyMOL. Tyr56, Tyr103 in heavy chain and Gly30, Ile31 in light chain of olokizumab were mutated with residues Ser, Thr, Tyr, Trp, and Phe. A set of 899 mutant macromolecules were designed, and binding affinity of these macromolecules to IL-6 was evaluated through Ag???Ab docking (ZDOCK, ClusPro, and Rosetta server), binding free-energy calculations using Molecular Mechanics/Poisson Boltzman Surface Area (MM/PBSA) method, and interaction energy estimation. In comparison to olokizumab, eight newly designed theoretical antibodies demonstrated better result in all assessments. Therefore, these newly designed macromolecules were proposed as potential lead antibodies to serve as a therapeutics option for IL-6-mediated diseases. 相似文献
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