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211.
212.
S.K. Srivastava K.S. Gopalkrishnan K.B. Ramachandran 《Enzyme and microbial technology》1984,6(11):508-512
The kinetic characteristics of β-d-glucosidase (cellobiase, β-d-glucosidase glucohydrolase, EC 3.2.1.21) from the filtered broth of a well grown culture of Aspergillus wentii have been studied. Both cellobiose and 4-nitrophenyl-β-d-glucoside (4NPG) were used as substrates and values of Km, Vmax for both the substrates were determined. Activity was maximum over a pH range of 4.5–5.5 but declined sharply beyond 5.5 for both substrates. The optimum temperature was between 60 and 65°C. Half-life of the cellobiase was ~38.0 h at 60°C and ~6.3 h at 65°C. However, the enzyme was found to be quite stable at 50°C. The activation and deactivation energies for 4NPG hydrolysis were 33.2 and 111.3 kJ mol?1 K?1, and 43.6 and 63.7 kJ mol K?1 for cellobiose hydrolysis. Product inhibition was found to be of the competitive type. Preliminary experiments showed that marked synergistic activity exists between Trichoderma reesei and A. wentii cellulases [see 1,4-(1,3;1,4)-β-d-glucan 4-glucanohydrolase, EC 3.2.1.4] for cellulose hydrolysis. 相似文献
213.
Bernard Voirin Jean Favre-Bonvin V. Indra A.G.Ramachandran Nair 《Phytochemistry》1984,23(12):2973-2975
Majoranin isolated from Majorana hortensis and characterized earlier as 5,7,4′-trihydroxy-6,8,3′-trimethoxyflavone was found to be different from sudachitin of the same structure. Its true structure has been established as 5,6,4′-trihydroxy-7,8,3′-trimethoxyflavone (thymonin) by spectral data and direct comparison. 相似文献
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215.
P. Veeraraghavan Ramachandran Daniel R. Nicponski Hari N.G. Nair Matthew A. Helppi Pravin D. Gagare C. Max Schmidt Michele T. Yip-Schneider 《Bioorganic & medicinal chemistry letters》2013,23(24):6911-6914
Aminated α-methylene-γ-butyrolactones, which are readily synthesized with facile control of the diastereoisomerism, provide an economical and commercially-viable alternative to the use of aminated natural products. These aminoloactones, which exhibit excellent activity against three pancreatic cancer cell lines when measured at 10 μM—Panc-1, MIA PaCa-2, and BxPC-3—and are comparable to or better than parthenolide and dimethylaminoparthenolide (DMAPT, LC-1). It has also been shown that there is an effect on the biological activity depending on the identity of the amine. 相似文献
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Unsaturated methyl esters were cleaved to aldehydes and aldehydo-esters by ozonolysis followed by reduction with dimethyl sulfide after conversion to hydroperoxides. Cleavage products were identified by thin-layer chromatography and quantified by temperature programmed gas-liquid chromatography. 相似文献
218.
Knowledge and understanding of the epidemiological profile is an essential pre-requisite to assess and address public health
needs in the country and to enable efficient programme planning and management. The need for adequate and accurate health
information and data to undertake such an exercise cannot be over-emphasized. The present effort is a modest attempt to critically
analyse the epidemiological profile of India from the historical and contemporary perspective. In order to assess the successes
achieved as well caution against the daunting challenges awaiting the country, parameters such as disease burden and health
status indicators, are increasingly being used. Changes in the population age structure, improvements in the nation’s economic
status, altered life-styles of people and duality of disease burden testify to the demographic, development and health transition
occurring in the country. Population stabilization, poverty alleviation, life-style modification, surveillance and control
of communicable and non-communicable diseases constitute the major challenges demanding urgent attention in the future. 相似文献
219.
Balawant Kumar Chakrapani Tripathi Ranjana K. Kanchan Jitendra Kumar Tripathi Jimut K. Ghosh Ravishankar Ramachandran Smrati Bhadauria Raj Kamal Tripathi 《PloS one》2013,8(6)
FasL mediated preferential apoptosis of bystander CTLs while protection of infected CD4+T cells remains one of the hallmarks of immune evasion during HIV infection. The property of infected host cells to evade cell-autonomous apoptosis emanates from ability of HIV-1Nef -protein to physically interact with ASK-1 and thereby inhibit its enzymatic activity. The specific domains of HIV-1Nef through which it may interact with ASK1 and thereby impair the ASK1 activity remain unidentified so far and represent a major challenge towards developing clear understanding about the dynamics of this interaction. Using mammalian two hybrid screen in association with site directed mutagenesis and competitive inhibitor peptides, we identified constituent minimal essential domain (152 DEVGEANN 159) through which HIV-1Nef interacts with ASK1 and inhibits its function. Furthermore our study also unravels a novel alternate mechanism underlying HIV-1 Nef mediated ASK1 functional modulation, wherein by potentiating the inhibitory ser967 phosphorylation of ASK1, HIV-1Nef negatively modulated ASK1function. 相似文献
220.