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Gurdeep Rattu Swati Joshi T. Satyanarayana 《Extremophiles : life under extreme conditions》2016,20(6):831-842
The thermostable bifunctional CMCase and xylanase encoding gene (rBhcell-xyl) from Bacillus halodurans TSLV1 has been expressed in Escherichia coli. The recombinant E. coli produced rBhcell-xyl (CMCase 2272 and 910 U L?1 xylanase). The rBhcell-xyl is a ~62-kDa monomeric protein with temperature and pH optima of 60 °C and 6.0 with T1/2 of 7.0 and 3.5 h at 80 °C for CMCase and xylanase, respectively. The apparent K m values (CMC and Birchwood xylan) are 3.8 and 3.2 mg mL?1. The catalytic efficiency (k cat/K m ) values of xylanase and CMCase are 657 and 171 mL mg?1 min?1, respectively. End-product analysis confirmed that rBhcell-xyl is a unique endo-acting enzyme with exoglucanase activity. The rBhcell-xyl is a GH5 family enzyme possessing single catalytic module and carbohydrate binding module. The action of rBhcell-xyl on corn cobs and wheat bran liberated reducing sugars, which can be fermented to bioethanol and fine biochemicals. 相似文献
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Hridya Hemachandran Amrita Anantharaman Rajendra Rao Priya George Priya Doss 《Nucleosides, nucleotides & nucleic acids》2016,35(4):195-210
Catechin, a yellow colored molecule obtained from the wood of Acacia catechu was analyzed for its interaction with synthetic DNA duplexes using spectroscopic analysis. UV-Visible spectroscopic analysis revealed the non-intercalative binding mode. Fourier Transform Infrared spectroscopy (FTIR) analysis expose chemical shift indicated by various vibrational stretches and an increase in the intensity of base stacking was observed by Circular Dichroism (CD), respectively. This inference was further confirmed through nuclear staining technique and also in electrophoretic technique; the dye quenches the fluorescent intensity of ethidium bromide. The result of fluorescence spectroscopy was in concordance with the electrophoretic technique. In addition, the spectroscopic results were in accordance with the molecular docking studies of specific catechin compound from the catechu dye with CT-DNA. This kind of site specificity is a gain in the medicinal field as the drug can be DNA targeted for cancer therapeutics. The present work reveals that catechu dye has a noteworthy application in the field of medical bioscience. 相似文献
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Salicylic acid induces amelioration of chromium toxicity and affects antioxidant enzyme activity in Sorghum bicolor L. 总被引:1,自引:0,他引:1
Aim: Chromium (Cr(VI)) would inflict serious morphological, metabolic, and physiological anomalies in plants ranging from chlorosis of shoot to lipid peroxidation and protein degradation. Cr(VI) toxicity is often associated with oxidative stress, caused by the excessive formation of reactive oxygen species (ROS). In response, plants are equipped with a repertoire of mechanisms to counteract heavy metal (HM) toxicity. Salicylic acid (SA) plays a key role in the signal transduction pathways of various stress responses, demonstrating the protective effect of SA against abiotic stress factors. So, the present investigation was carried out to study the amelioration of pernicious effects of different concentration of Cr(VI) (0.0, 2.0, and 4.0?mg Cr(VI) kg?1 soil in the form of potassium dichromate) by treatments of salicylic acid solution viz. pretreatment and foliar spray via antioxidative enzymes and their metabolites.Results: With different treatments of salicylic acid solution, the reinstatement from ill effects of Cr(VI) toxicity was contemplated but the most conspicuous effect was observed when salicylic acid solution was supplied through the foliar spray (0.50?mM). This was accompanied with an increase in ascorbate peroxidase activity and hydrogen peroxide content and decrease in peroxidase activity and ascorbic acid content.Significance of the study: This study suggests that salicylic acid when applied through pre-treatment of seeds or through a foliar spray can be used to ameliorate the toxic effects of chromium (VI). Salicylic acid has the great potential for reducing the toxicity of heavy metals without negatively impacting the growth of the plants. 相似文献
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Debnath Bhuniya Rajendra K. Kharul Atul Hajare Nadim Shaikh Sandeep Bhosale Sandip Balwe Fouzia Begum Siddhartha De Sonalee Athavankar Dhananjay Joshi Vamsi Madgula Kaushal Joshi Amol A. Raje Ashwinkumar V. Meru Amol Magdum Kasim A. Mookhtiar Rashmi Barbhaiya 《Bioorganic & medicinal chemistry letters》2019,29(2):238-243
Conceptual design and modification of urea moiety in chemotype PF-3845/04457845, the bench marking irreversible inhibitor of fatty acid amide hydrolase (FAAH), led to discovery of a novel nicotinamide-based lead 12a having reversible mechanism of action. Focused SAR around the pyridine heterocycle (Ar) in 12a (Tables 1 and 2) resulted into four shortlisted compounds, (?)-12a, (?)-12i, (?)-12l–m. The required (?)-enantiomers were obtained via diastereomeric resolution of a novel chiral dissymmetric intermediate 15. Based on comparative profile of FAAH potency, metabolic stability in liver microsome, liability of inhibiting major hCYP450 isoforms, rat PK, and brain penetration ability, two SAR optimized compounds, (?)-12l and (?)-12m, were selected for efficacy study in rat model of chemotherapy-induced peripheral neuropathy (CIPN). Both the compounds exhibited dose related antihyperalgesic effects, when treated with 3–30?mg/kg po for 7?days. The effects at 30?mg/kg are comparable to that of PF-04457845 (10?mg/kg) and Tramadol (40?mg/kg). 相似文献
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