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341.
Alpettiyil Nisha Navin Kumar Rastogi Govindarjulu Venkateswaran 《Biotechnology and Bioprocess Engineering》2011,16(2):229-237
Mortierella alpina, an oleaginous zygomycete is a potent producer of arachidonic acid, the pharmaceutically and nutraceutically important polyunsaturated
fatty acid of the n-6 series. It serves a wide variety of purposes, from being a purely structural element in phospholipids
to being involved in signal transduction, and as a substrate for a host of derivatives involved in second messenger function.
Arachidonic acid has applications in diverse areas including infant and geriatric nutrition. In the present study, the interactive
effects of four major media constituents on arachidonic acid production were investigated by applying a central composite
rotatable design (CCRD) and response surface methodology (RSM). The independent variables, which were selected byconcentrations
of glucose, corn solids, KH2PO4, and KNO3 influenced the production of biomass, total lipid, and arachidonic acid by M. alpina. A second-order polynomial was fitted by multiple regression analysis of the experimental data. The optimum conditions (glucose
10.0 g/L, corn solids 5.0 g/L, KH2PO4 1.0 g/L, and KNO3 1.0 g/L) resulted in maximum production of arachidonic acid (1.39 g/L) and the corresponding biomass and total lipid concentrations
were 12.49 and 5.87 g/L, respectively. 相似文献
342.
Mathew N Srinivasan L Karunan T Ayyanar E Muthuswamy K 《Journal of molecular modeling》2011,17(10):2651-2657
Eleven 1,4-naphthoquinone analogues with different amino substitutions at position 3 of the quinone ring earlier reported
for macrofilaricidal activity were selected and screened against purified cytosolic GST isolated from the bovine filarial
worm Setaria digitata and IC50 values were determined. Of the 11 compounds tested, 8 showed good inhibition against S. digitata GST. The IC50 values of the most effective macrofilaricidal compounds—11 [2-(4-methylpiperazin-1-yl)naphthalene-1,4-dione] and 9 {2-[(1,3-dimethylbutyl)amino]naphthalene -1,4-dione}—were 0.872 and 0.994 mM, respectively. Compounds 9 and 11 were further studied for type of enzyme inhibition and found to exhibit competitive and uncompetitive inhibition kinetics,
respectively, with respect to substrate GSH. All 11 compounds were in agreement with Lipinski’s rule of five and passed through
the FAFDrugs ADME/tox filter. Molecular docking was carried out using the modeled 3D structure of wbGST PDB ID:1SFM as receptor and substituted naphthoquinones as ligands using AutoDock 4.0. The binding energy of nine compounds
varied from −9.15 to −6.58 Kcal mol−1, whereas compounds 8 and 10 did not show any binding to the receptor. Among the compounds studied, compound 7 {2-[3-(diethylamino) propyl]aminonaphthalene-1,4-dione} showed maximum affinity towards wbGST as it exhibited the lowest binding energy, followed by compounds 11 and 9. However compound 7 was not macrofilaricidal while 11 and 9 exhibited macrofilaricidal activity. The results of in silico and in vitro studies with the synthesized 1,4 -naphthoquinone
analogues on filarial GST and in vitro macrofilaricidal activity against adult bovine filarial worm S. digitata open up a promising biochemical target for antifilarial drug development. 相似文献
343.
Recent advances in the use of Sus scrofa (pig) as a model system for proteomic studies 总被引:1,自引:0,他引:1
Of the numerous animal models available for proteomic studies only a small number have been successfully used in understanding human biology. To date, rodents have been widely employed in proteomic and genomic studies but often these models do not truly mimic the relevant human conditions. On the other hand, the pig shows similarity in size, shape and physiology to human and has been used as a major mammalian model for many studies concerning xenotransplantation, cardiovascular diseases, blood dynamics, nutrition, general metabolic functions, digestive-related disorders, respiratory diseases, diabetes, kidney and bladder diseases, organ-specific toxicity, dermatology and neurological sequelae. With the substantially improved knowledge of the structure and function of the pig genome in the last two decades it has been found that this animal shares a high sequence and chromosomal structure homology with humans. Nevertheless, in comparison to other available model organisms, very little work has been devoted to pig proteomics until recently. Keeping this in mind, the present review will highlight some of the advantages and disadvantages of pig as a model system for proteomic studies. 相似文献
344.
Nisha S. Wadhwani Kamini D. Dangat Asmita A. Joshi Sadhana R. Joshi 《Prostaglandins, leukotrienes, and essential fatty acids》2013,88(3):235-242
Adequate supply of LCPUFA from maternal plasma is crucial for fetal normal growth and development. The present study examines the effect of maternal micronutrients (folic acid and vitamin B12) and omega 3 fatty acids on placental mRNA levels of fatty acid desaturases (Δ5 and Δ6) and transport proteins. Pregnant female rats were divided into 6 groups at 2 levels of folic acid both in the presence and absence of vitamin B12. Both the vitamin B12 deficient groups were supplemented with omega 3 fatty acid. Maternal vitamin B12 deficiency reduced placental mRNA and protein levels of Δ5 desaturase, mRNA levels of FATP1 and FATP4 (p<0.05 for all) as compared to control while omega 3 fatty acid supplementation normalized the levels. Our data for the first time indicates that altered maternal micronutrients and omega 3 fatty acids play a key role in regulating fatty acid desaturase and transport protein expression in placenta. 相似文献
345.
AbstractPurified Acetobacter tropicalis dextransucrase was immobilized in different matrices viz. calcium-alginate, κ-carrageenan, agar, agarose and polyacrylamide. Calcium-alginate was proved to be superior to the other matrices for immobilization of dextransucrase enzyme. Standardization of immobilization conditions in calcium-alginate resulted in 99.5% relative activity of dextransucrase. This is the first report with such a large amount of relative activity as compared to the previous reports. The immobilized enzyme retained activity for 11 batch reactions without a decrease in activity which suggested that enzyme can be used repetitively for 11 cycles. The dextransucrase was also characterized, which revealed that enzyme worked best at pH 5.5 and 37?°C for 30?min in both the free as well as immobilized state. Calcium-alginate immobilized dextransucrase of A. tropicalis showed the Km and Vmax values of 29?mM and 5000?U/mg, respectively. Free and immobilized enzyme produced 5.7?mg/mL and 2.6?mg/mL of dextran in 2?L bench scale fermenter under optimum reaction conditions. This immobilization method is very unconventional for purified large molecular weight dextran-free dextransucrase of A. tropicalis as this method is used usually for cells. Such reports on entrapment of purified enzyme are rarely documented. 相似文献
346.
Hukam Singh Gehlot Nisha Tak Muskan Kaushik Shubhajit Mitra Wen-Ming Chen Nicole Poweleit Dheeren Panwar Neetu Poonar Rashmita Parihar Alkesh Tak Indu Singh Sankhla Archana Ojha Satyawada Rama Rao Marcelo F. Simon Fabio Bueno dos Reis Junior Natalia Perigolo Anil K. Tripathi Janet I. Sprent J. Peter W. Young Euan K. James Prasad Gyaneshwar 《Annals of botany》2013,112(1):179-196
Background and Aims
The large monophyletic genus Mimosa comprises approx. 500 species, most of which are native to the New World, with Central Brazil being the main centre of radiation. All Brazilian Mimosa spp. so far examined are nodulated by rhizobia in the betaproteobacterial genus Burkholderia. Approximately 10 Mya, transoceanic dispersal resulted in the Indian subcontinent hosting up to six endemic Mimosa spp. The nodulation ability and rhizobial symbionts of two of these, M. hamata and M. himalayana, both from north-west India, are here examined, and compared with those of M. pudica, an invasive species.Methods
Nodules were collected from several locations, and examined by light and electron microscopy. Rhizobia isolated from them were characterized in terms of their abilities to nodulate the three Mimosa hosts. The molecular phylogenetic relationships of the rhizobia were determined by analysis of 16S rRNA, nifH and nodA gene sequences.Key Results
Both native Indian Mimosa spp. nodulated effectively in their respective rhizosphere soils. Based on 16S rRNA, nifH and nodA sequences, their symbionts were identified as belonging to the alphaproteobacterial genus Ensifer, and were closest to the ‘Old World’ Ensifer saheli, E. kostiensis and E. arboris. In contrast, the invasive M. pudica was predominantly nodulated by Betaproteobacteria in the genera Cupriavidus and Burkholderia. All rhizobial strains tested effectively nodulated their original hosts, but the symbionts of the native species could not nodulate M. pudica.Conclusions
The native Mimosa spp. in India are not nodulated by the Burkholderia symbionts of their South American relatives, but by a unique group of alpha-rhizobial microsymbionts that are closely related to the ‘local’ Old World Ensifer symbionts of other mimosoid legumes in north-west India. They appear not to share symbionts with the invasive M. pudica, symbionts of which are mostly beta-rhizobial. 相似文献347.
Shraddha Thakkar Nisha Nanaware-Kharade Guillermo Gonzalez III Reha Celikel Eric Peterson 《Journal of biomolecular structure & dynamics》2013,31(1):112-113
Methamphetamine (METH) abuse is a major threat in the USA and worldwide without any FDA approved medications. Anti-METH antibody antagonists block or slow the rate of METH entry into the brain and have shown efficacy in preclinical studies (Peterson, Laurenzana, Atchley, Hendrickson, & Owens, 2008).?A key determinant of the antibody’s efficacy is its affinity for METH and we attempted to enhance the efficacy by designing mutations to alter the shape or the electrostatic character of the binding pocket. Towards this goal, we developed a single chain anti-METH antibody fragment (scFv6H4) from a parent IgG (1). The crystal structure of scFv-6H4 in complex with METH was determined (Celikel, Peterson, Owens, & Varughese, 2009). Based on its elucidated binding interactions, we designed point mutations in the binding pocket to improve its affinity for METH and amphetamine (AMP), the active metabolite of METH. The mutants, scFv-S93T,-I37?M and -Y34?M were cloned, expressed in yeast and tested for affinity against METH and AMP. Two mutants showed enhanced binding affinity for METH: scFv-I37?M by 1.3-fold and scFv-S93T by 2.6-fold. Additionally, all the mutants showed increase in affinity for AMP: scFv-I37?M by 56-fold, scFv-S93T by 17-fold and scFvY34?M by 5-fold. Crystal structure for one of the high-affinity mutant, scFv-S93T, in complex with METH was determined (Figure 1). Binding pocket of the mutant is more hydrophobic in comparison with the wild type. ScFv-6H4 binds METH in a deep pocket containing two water molecules. The substitution of a serine residue by a threonine leads to the expulsion of a water molecule (Figure 2), relieving some unfavorable contacts between the hydrocarbon atoms of METH and the water molecule and increasing the affinity to sub-nanomolar range. Therefore, the present study shows that efficacy could be enhanced by altering the hydrophobicity or the shape of the binding pocket. 相似文献
348.
Nisha Singh Pallavi Kansal Zeeshan Ahmad Navin Baid Hariom Kushwaha Neeraj Khatri 《Autophagy》2018,14(6):972-991
349.
Shabnam Nisha Sharmila P. Sharma Anuradha Strasser Reto J. Govindjee Pardha-Saradhi P. 《Photosynthesis research》2015,125(1-2):305-319
Photosynthesis Research - Investigations were carried to unravel mechanism(s) for higher tolerance of floating over submerged leaves of long leaf pondweed (Potamogeton nodosus Poir) against... 相似文献
350.
David A. Andersson Milos R. Filipovi? Clive Gentry Mirjam Eberhardt Nisha Vastani Andreas Leffler Peter Reeh Stuart Bevan 《The Journal of biological chemistry》2015,290(24):15185-15196
Streptozotocin (STZ)-induced diabetes is the most commonly used animal model of diabetes. Here, we have demonstrated that intraplantar injections of low dose STZ evoked acute polymodal hypersensitivities in mice. These hypersensitivities were inhibited by a TRPA1 antagonist and were absent in TRPA1-null mice. In wild type mice, systemic STZ treatment (180 mg/kg) evoked a loss of cold and mechanical sensitivity within an hour of injection, which lasted for at least 10 days. In contrast, Trpa1−/− mice developed mechanical, cold, and heat hypersensitivity 24 h after STZ. The TRPA1-dependent sensory loss produced by STZ occurs before the onset of diabetes and may thus not be readily distinguished from the similar sensory abnormalities produced by the ensuing diabetic neuropathy. In vitro, STZ activated TRPA1 in isolated sensory neurons, TRPA1 cell lines, and membrane patches. Mass spectrometry studies revealed that STZ oxidizes TRPA1 cysteines to disulfides and sulfenic acids. Furthermore, incubation of tyrosine with STZ resulted in formation of dityrosine, suggesting formation of peroxynitrite. Functional analysis of TRPA1 mutants showed that cysteine residues that were oxidized by STZ were important for TRPA1 responsiveness to STZ. Our results have identified oxidation of TRPA1 cysteine residues, most likely by peroxynitrite, as a novel mechanism of action of STZ. Direct stimulation of TRPA1 complicates the interpretation of results from STZ models of diabetic sensory neuropathy and strongly argues that more refined models of diabetic neuropathy should replace the use of STZ. 相似文献