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751.
Notch is a single-pass transmembrane receptor protein. Delta (member of the DSL protein family), a Notch ligand, is also single-pass transmembrane protein that can interact with Notch to form the Delta-Notch complex. It has been demonstrated that of the 36 Epidermal Growth Factor (EGF) repeats of Notch, 11th and 12th are sufficient to mediate interactions with Delta. Crystal structure of mammalian Notch1 extracellular ligand binding domain shows the presence of 11th and 12th EGF-like repeats. Here a portion of the Drosophila Delta protein, known to interact with Notch extracellular domain, has been modeled using homology modeling. The structure of the Delta-Notch complex was subsequently modeled by protein-docking method using GRAMM. Molecular dynamic simulations of the modeled structures were performed. The probable structures for Delta-Notch complex have been proposed based on interaction energy parameter and planarity studies. 相似文献
752.
Mishra R Jayaraman M Roland BP Landrum E Fullam T Kodali R Thakur AK Arduini I Wetzel R 《Journal of molecular biology》2012,415(5):900-917
Although oligomeric intermediates are transiently formed in almost all known amyloid assembly reactions, their mechanistic roles are poorly understood. Recently, we demonstrated a critical role for the 17-amino-acid N-terminus (htt(NT) segment) of huntingtin (htt) in the oligomer-mediated amyloid assembly of htt N-terminal fragments. In this mechanism, the htt(NT) segment forms the α-helix-rich core of the oligomers, leaving much of the polyglutamine (polyQ) segment disordered and solvent-exposed. Nucleation of amyloid structure occurs within this local high concentration of disordered polyQ. Here we demonstrate the kinetic importance of htt(NT) self-assembly by describing inhibitory htt(NT)-containing peptides that appear to work by targeting nucleation within the oligomer fraction. These molecules inhibit amyloid nucleation by forming mixed oligomers with the htt(NT) domains of polyQ-containing htt N-terminal fragments. In one class of inhibitors, nucleation is passively suppressed due to the reduced local concentration of polyQ within the mixed oligomer. In the other class, nucleation is actively suppressed by a proline-rich polyQ segment covalently attached to htt(NT). Studies with D-amino acid and scrambled sequence versions of htt(NT) suggest that inhibition activity is strongly linked to the propensity of inhibitory peptides to make amphipathic α-helices. Htt(NT) derivatives with C-terminal cell-penetrating peptide segments also exhibit excellent inhibitory activity. The htt(NT)-based peptides described here, especially those with protease-resistant d-amino acids and/or with cell-penetrating sequences, may prove useful as lead therapeutics for inhibiting the nucleation of amyloid formation in Huntington's disease. 相似文献
753.
Malhotra Bharti Huddone Suhasini Verma Ashwani Chamail Anjali Sanju Suman Thakur Aditi Sindhu Ritu Singh Youvika Patil Virupaksh U. Siddappa Sundaresha Gupta Reena Pattanayak Debasis 《Journal of plant biochemistry and biotechnology.》2012,21(1):90-99
Biotechnology is one of the fastest growing, knowledge-driven industries in India and is expected to play a key role in shaping India’s rapidly developing economy. Since its inception in 1986 the Department of Biotechnology (DBT) has been guiding to foster growth of Indian biotechnology with a range of initiatives. Indian biotechnology industry registered over 3.0 billion USD revenue generation in 2009–10, which constitutes about 2 % share of the global biotechnology market. More than 300 companies are engaged in different biotechnology sectors in India, majority of which are clustered in western and southern regions. Biopharmaceuticals is the largest biotechnology sector in India with about 62 % market share. Bioservices ranked second due to the upward trend in a range of service oriented research activities. Bioagriculture recorded highest growth in 2009–10 and is dominated by insect resistant transgenic cotton. Bioindustrial, which deals with production of enzymes for different industrial uses, is the smallest biotechnology sector in India with 6 % revenue share. 相似文献
754.
Malay Shukla Bheem Dutt Joshi Ved Prakash Kumar Mukesh Thakur Anil Kumar Mehta Sambandam Sathyakumar 《Animal biotechnology》2019,30(3):193-201
Musk deer are of high conservation priority owing to poaching pressure because of its musk pod. Representation of musk deer status using genetics is poorly documented in India, and it is not confirmed as to how many species of musk deer are present. We characterize for the first time, the genetic diversity of musk deer from Uttarakhand using Cytochrome Oxidase sub-unit (COI) gene (486?bp) and compared with the data available for other species. Results revealed the presence of six haplotypes in the Uttarakhand population amongst 17 sequences. Of these, 12 sequences shared the single haplotype. The intra-species sequences divergence was 0.003–0.017, whereas divergence with other species of musk deer was 0.071–0.081. Bayesian phylogenetic tree revealed that samples from Uttarakhand formed a separate clade with respect to other species of musk deer, whereas three species distributed in China clustered in the same clade and showed low sequences divergence, i.e., 0.002–0.061. Because of different ecomorph reported, we suggest using the barcoding based approach for inter and intra-species distinction and delineating species boundaries across the range for effective conservation. Besides, systematic classification, DNA barcoding would also help in dealing wildlife offence cases for disposal of the legal report in court. 相似文献
755.
Nipah virus is an emerging zoonotic paramyxovirus that causes severe and often fatal respiratory and neurological disease in humans. The virus was first discovered after an outbreak of encephalitis in pig farmers in Malaysia and Singapore with subsequent outbreaks in Bangladesh or India occurring almost annually. Due to the highly pathogenic nature of NiV, its pandemic potential, and the lack of licensed vaccines or therapeutics, there is a requirement for research and development into highly sensitive and specific diagnostic tools as well as antivirals and vaccines to help prevent and control future outbreak situations. 相似文献
756.
Darren P. Giling La Beaumelle Helen R. P. Phillips Simone Cesarz Nico Eisenhauer Olga Ferlian Felix Gottschall Carlos Guerra Jes Hines Agnieszka Sendek Julia Siebert Madhav P. Thakur Andrew D. Barnes 《Global Change Biology》2019,25(3):763-774
Concern about human modification of Earth's ecosystems has recently motivated ecologists to address how global change drivers will impact the simultaneous provisioning of multiple functions, termed ecosystem multifunctionality (EMF). However, metrics of EMF have often been applied in global change studies with little consideration of the information they provide beyond single functions, or how and why EMF may respond to global change drivers. Here, we critically review the current state of this rapidly expanding field and provide a conceptual framework to guide the effective incorporation of EMF in global change research. In particular, we emphasize the need for a priori identification and explicit testing of the biotic and abiotic mechanisms through which global change drivers impact EMF, as well as assessing correlations among multiple single functions because these patterns underlie shifts in EMF. While the role of biodiversity in mediating global change effects on EMF has justifiably received much attention, empirical support for effects via other biotic and physicochemical mechanisms are also needed. Studies also frequently stated the importance of measuring EMF responses to global change drivers to understand the potential consequences for multiple ecosystem services, but explicit links between measured functions and ecosystem services were missing from many such studies. While there is clear potential for EMF to provide novel insights to global change research, predictive understanding will be greatly improved by insuring future research is strongly hypothesis‐driven, is designed to explicitly test multiple abiotic and biotic mechanisms, and assesses how single functions and their covariation drive emergent EMF responses to global change drivers. 相似文献
757.
Kumar Anil Thakur Avinash Panesar Parmjit Singh 《Reviews in Environmental Science and Biotechnology》2019,18(4):823-853
Reviews in Environmental Science and Bio/Technology - In this current review article, a significant number of published articles were reviewed in order to provide comprehensive literature... 相似文献
758.
(1) Presenilin (PS) expression is regulated by several cellular and extracellular factors which change with age and sex. Both
age and sex are key risk factors for Alzheimer’s disease (AD), which is linked to mutations in PS genes. (2) We have analyzed
the effect of age and sex on PS expression by northern hybridization and western blot analysis using the cerebral cortex of
adult (24 ± 2 weeks) and old (65 ± 5 weeks) mice. (3) Our results demonstrate that PS1 was downregulated and PS 2 was upregulated
in old mice of both sexes. The level of PS 1 was relatively higher and that of PS 2 was lower in female than male mice of
same age group. Taken together, these findings show age and sex dependent alteration in PS expression, which in turn may influence
the signal transduction pathways and consequently brain functions. 相似文献
759.
Atul Thakur Monika Rana T.N. Lakhanpal Absar Ahmad M.I. Khan 《Biochimica et Biophysica Acta (BBA)/General Subjects》2007
A novel 114 kDa hexameric lectin was purified from the fruiting bodies of the mushroom Ganoderma lucidum. Biochemical characterization revealed it to be a glycoprotein having 9.3% neutral sugar and it showed hemagglutinating activity on pronase treated human erythrocytes. The lectin was stable in the pH range of 5–9 and temperature up to 50 °C. The hemagglutinating activity was inhibited by glycoproteins that possessed N-as well as O-linked glycans. Chemical modification of the G. lucidum lectin revealed contribution of tryptophan and lysine to binding activity. The thermodynamics of binding of bi- and triantennary N-glycans to G. lucidum lectin was studied by spectrofluorimetry. The lectin showed very high affinity for asialo N-linked triantenary glycan and a preference for asialo glycans over sialylated glycans. The binding was accompanied with a large negative change in enthalpy as well as entropy, indicating primarily involvement of polar hydrogen, van der Waals and hydrophobic interactions in the binding. 相似文献
760.
Two bacterial consortia were developed by continuous enrichment of microbial population of tannery and pulp and paper mill
effluent contained Serratia mercascens, Pseudomonas fluorescence, Escherichia coli, Pseudomonas aeruginosa and Acinetobacter sp. identified by 16S rDNA method. The consortia evaluated for removal of chromate [(Cr(VI)] in shake flask culture indicated
pulp and paper mill consortium had more potential for removal of chromate. Acinetobacter sp. isolated from pulp and paper mill consortium removed higher amount of chromate [Cr(VI)] under aerobic conditions. Parameters
optimized in different carbon, nitrogen sources, and pH, indicated maximum removal of chromate in sodium acetate (0.2%), sodium
nitrate (0.1%) and pH 7 by Acinetobacter sp. Bacteria was applied in 2-l bioreactor significantly removed chromate after 3 days. The results of the study indicated
removal of more than 75% chromium by Acinetobacter sp. determined by diphenylcarbazide colorimetric assay and atomic absorption spectrophotometer after 7 days. Study of microbial
[Cr(VI)] removal and identification of reduction intermediates has been hindered by the lack of analytical techniques. Therefore,
removal of chromium was further substantiated by transmission electron microscopy (TEM), scanning electron microscopy (SEM)
and energy-dispersive X-ray spectroscopy (EDX) which indicated bioaccumulation of chromium in the bacterial cells. 相似文献