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1.
Besides vobtusine and vobtusine-lactone, deoxyvobtusine was isolated from the leaves of Voacanga grandifolia (Miq. Rolfe. Spectral and chemical evi 相似文献
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Priya Padmanabhan Mukund R. Shukla J. Alan Sullivan Praveen K. Saxena 《Plant Cell, Tissue and Organ Culture》2017,128(1):145-160
C4 plants can efficiently accumulate CO2 in leaves and thus reduce wasteful oxygen fixation by the RuBisCO enzyme. Three C4 enzymes, namely carbonic anhydrase (CA), phosphoenol pyruvate (PEPC) and pyruvate orthophosphate dikinase (PPDK), were over expressed in Oryza sativa L. ssp. indica var. Khitish under the control of green tissue specific promoters PD54o, PEPC and PPDK, respectively. Integration of these genes was confirmed by Southern hybridization. The relative expression of PEPC, CA and PPDK were, respectively, 6.75, 6.57 and 3.6-fold higher in transgenic plants compared to wild type plants (control). Photosynthetic efficiency of the transgenic plants increased significantly along with a 12?% increase in grain yield compared to wild type plants. Compared to control plants, transgenic plants also showed phenotypic changes such as increased leaf blade size, root biomass, and plant height and anatomical changes such as greater leaf vein number, bundle sheath cells, and bulliform cells. Our findings indicate that the combined over expression of these three enzymes is an efficient strategy for incorporating beneficial physiological and anatomical features that will enable subsequent yield enhancement in C3 rice plants. 相似文献
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George Priya Doss C Rajasekaran R Sudandiradoss C Ramanathan K Purohit R Sethumadhavan R 《Genomic Medicine》2008,2(1-2):23-32
Single Nucleotide Polymorphisms (SNPs) are being intensively studied to understand the biological basis of complex traits and diseases. The Genetics of human phenotype variation could be understood by knowing the functions of SNPs. In this study using computational methods, we analyzed the genetic variations that can alter the expression and function of the CFTR gene responsible candidate for causing cystic fibrosis. We applied an evolutionary perspective to screen the SNPs using a sequence homology-based SIFT tool, which suggested that 17 nsSNPs (44%) were found to be deleterious. The structure-based approach PolyPhen server suggested that 26 nsSNPS (66%) may disrupt protein function and structure. The PupaSuite tool predicted the phenotypic effect of SNPs on the structure and function of the affected protein. Structure analysis was carried out with the major mutation that occurred in the native protein coded by CFTR gene, and which is at amino acid position F508C for nsSNP with id (rs1800093). The amino acid residues in the native and mutant modeled protein were further analyzed for solvent accessibility, secondary structure and stabilizing residues to check the stability of the proteins. The SNPs were further subjected to iHAP analysis to identify htSNPs, and we report potential candidates for future studies on CFTR mutations. 相似文献
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Microtubules are dynamic polymers that participate in multiple cellular processes such as vesicular transport and cell division. Microtubule dynamics alter dramatically during the cell cycle. An excellent system to study microtubule dynamics is Xenopus egg extracts since it is a system that is open to manipulation. The extracts can be cycled between mitosis and interphase allowing the study of microtubules in these phases as well as during cell cycle transitions. Here, we provide simple assays to study microtubules in extracts and in vitro using purified components. Protocols are provided for the purification of frog tubulin, microtubule pelleting from extracts and in vitro, assembly of microtubule structures in extracts, and isolation of microtubule-associated proteins from extract. These methods can be used to analyze the effect of a protein of interest on the microtubule cytoskeleton. 相似文献
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C. George Priya Doss C. Debajyoti S. Debottam 《Cell biochemistry and biophysics》2013,67(3):1075-1079
Mitochondria are the fulcrum for regulating cellular metabolism as well as apoptosis. The multi-lamellar vesicles (MLVs) liposome targeted against mitochondria can be formulated to disrupt mitochondrial integrity to attain programmed cell death of cancer stem cells (CSCs). The gold nanoparticles (GNPs) and a steroid nucleus (cyclopentanoperhydrophenanthrene ring) are encapsulated within MLV liposome that targets specifically to the CD44 receptor of the CSCs. Entering cytosol, it would bind distinctively to the malate–aspartate shuttle through a specifically designed ligand. Liposome fuses with the mito-membrane after associating with shuttle, thereby releasing both the components. The steroid disrupts mito-membrane’s integrity facilitating release of cytochrome c. Thus, GNPs enter into the mitosol and interact with the mitochondrial complexes to cease cellular respiration. Since the solid nano-based pharmaceutics has shown a lot of promises as a potent anticancer therapy, the role of MLV liposome can be proved to be a better weapon to terminate malignancy. 相似文献
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Jayashrita Debnath Sooraj Kunnikuruvan Nishant Sinha Priya V. Parandekar Om Prakash Thomas K. Tsotsis 《Molecular simulation》2018,44(7):582-589
Coupled cascade reactions forming complex reaction networks can be commonly found in polymerisation reactions and other reactions involving radical intermediates. Predicting the mechanism and kinetics of such reactions requires proper modelling of complex reaction networks. This becomes particularly difficult when coupled cascade reactions occur in polymeric systems containing different types of residues. Here, we propose a residue-based database approach to model such reactions in polymers, with the aid of a visual interface developed here. We demonstrate this approach by predicting the oxidative degradation kinetics of high-performance polymers (HPPs). First, we show that residue-based reaction database can be linked to construct the whole reaction network. For this purpose, we developed a database for oxidation reactions of commonly occurring residues in industrially important HPPs. Then we implement a visual interface which takes inputs from a user about residues in a polymer of interest and subsequently link appropriate databases to build reaction network. Finally, this program executes numerical integration of rate equations in the back-end. Application of this approach and the developed program is demonstrated by studying the oxidative degradation kinetics of three well-known HPPs- PMR-15, HFPE-30 and PMR-II, where the computations took less than a minute in a conventional desktop computer. 相似文献