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261.
Hirdayesh Anuragi Rajesh Kumar Singhal Yashfa Tanveer Humaira Yasmin Ambati Srijan Alka Bharati Lal Chand Sukumar Taria Kunasekaran Rajarajan Asha Ram Arun Kumar Handa Ayyanadar Arunachalam Khalid Rehman Hakeem Deniz Özbilici Ayman EL Sabagh 《Phyton》2022,91(9):1831-1858
A severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) led novel coronavirus disease (COVID-19) outbreak spread through China has become the biggest global public health challenge today. The virus upon several mutations has led to the resurgence of more infectious and lethal variants infecting over 298 million people with more than 5.46 million deaths worldwide by the end of December, 2021. Though vaccines are available, various preventive measures particularly a high body immunity is still extremely important which determines the likelihood of disease severity and subsequent recovery in the current and future pandemics. This review acknowledges the potentiality of miraculous Moringa oleifera Lam. against recently evolved novel coronavirus and accompanying health complications. Moringa a well-proven super-food, densely packed with an abundant quantity of 92 minerals, several vitamins, 46 antioxidants, and numerous bioactive compounds, thus own a massive therapeutic potential for healing all levels of nutritional deficiencies and poor immunities and cure above 300 diseases. Moringa acts as anti-asthmatic, anti-cancerous, anti-diabetic, anti-inflammatory, hypotensive, hepatic, renal and cardio-protective, and anti-viral in nature. Thus it may reduce the severity of COVID-19 infections and associated serious medical emergencies. In addition, self-isolation at home or the workplace has put people at increased risk of physical and mental sicknesses, which could be simply addressed by integrating this wonderful plant into everyday diet. Furthermore, the immune-modulatory properties and viral inhibiting nature of moringa contribute to reduced risk of COVID-19 infection and quicker recovery from its symptoms. As per the existing pieces of literature, it is a great time to harness the esteemed moringa for safeguarding people from the terrible ongoing COVID-19 situation and other future pandemics. 相似文献
262.
Amino acids in the basic domain of Epstein-Barr virus ZEBRA protein play distinct roles in DNA binding, activation of early lytic gene expression, and promotion of viral DNA replication 下载免费PDF全文
Heston L El-Guindy A Countryman J Dela Cruz C Delecluse HJ Miller G 《Journal of virology》2006,80(18):9115-9133
The ZEBRA protein of Epstein-Barr virus (EBV) drives the viral lytic cycle cascade. The capacity of ZEBRA to recognize specific DNA sequences resides in amino acids 178 to 194, a region in which 9 of 17 residues are either lysine or arginine. To define the basic domain residues essential for activity, a series of 46 single-amino-acid-substitution mutants were examined for their ability to bind ZIIIB DNA, a high-affinity ZEBRA binding site, and for their capacity to activate early and late EBV lytic cycle gene expression. DNA binding was obligatory for the protein to activate the lytic cascade. Nineteen mutants that failed to bind DNA were unable to disrupt latency. A single acidic replacement of a basic amino acid destroyed DNA binding and the biologic activity of the protein. Four mutants that bound weakly to DNA were defective at stimulating the expression of Rta, the essential first target of ZEBRA in lytic cycle activation. Four amino acids, R183, A185, C189, and R190, are likely to contact ZIIIB DNA specifically, since alanine or valine substitutions at these positions drastically weakened or eliminated DNA binding. Twenty-three mutants were proficient in binding to ZIIIB DNA. Some DNA binding-proficient mutants were refractory to supershift by BZ-1 monoclonal antibody (epitope amino acids 214 to 230), likely as the result of the increased solubility of the mutants. Mutants competent to bind DNA could be separated into four functional groups: the wild-type group (eight mutants), a group defective at activating Rta (five mutants, all with mutations at the S186 site), a group defective at activating EA-D (three mutants with the R179A, S186T, and K192A mutations), and a group specifically defective at activating late gene expression (seven mutants). Three late mutants, with a Y180A, Y180E, or K188A mutation, were defective at stimulating EBV DNA replication. This catalogue of point mutants reveals that basic domain amino acids play distinct functions in binding to DNA, in activating Rta, in stimulating early lytic gene expression, and in promoting viral DNA replication and viral late gene expression. These results are discussed in relationship to the recently solved crystal structure of ZEBRA bound to an AP-1 site. 相似文献
263.
Ejaz Ahmad Waraich Zeeshan Ahmed Zahoor Ahmad Rashid Ahmad Murat Erman Fatih Cig Ayman El Sabagh 《Phyton》2020,89(3):587-597
Camelina (Camelina sativa L.) is famous for its oil quality and unique
fatty acid pattern. Growth and yield of crops reduced under water deficit conditions. Environmental threat such as drought or water deficit condition is the emerging problem which creates the negative impact on the growth of plants. Based
upon the current situation a pot study was performed in rain out-shelter to explore
the effect of different plant densities (15, 10 and 5 plants per pot) on growth and
seed yield of two camelina genotypes under normal (100% WHC) and water deficit (60% WHC) conditions by using completely randomized design with factorial
arrangement having three replicates. Results indicated that individual effects of
plant densities and water deficit stress levels considerably influenced the growth
and seed yield of camelina but interaction effects did not indicate any significant
variation. Maximum values of leaf area index (LAI) and crop growth rate (CGR)
were recorded in P3 treatment (15 plants per pot). However, maximum values of
leaf area duration (LAD), net assimilation rate (NAR), yield and yield components were observed in the treatment P1 (5 plants per pot). Water deficit condition
(60% WHC) significantly minimized the growth, seed yield (0.82 g/m2
) and yield
components of camelina genotypes. Both camelina genotypes (611 and 618) did
not differ significantly under water deficit conditions. 相似文献
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266.
Although having highly similar primary to tertiary structures, the different guanidino kinases exhibit distinct quaternary structures: monomer, dimer or octamer. However, no evidence for communication between subunits has yet been provided, and reasons for these different levels of quaternary complexity that can be observed from invertebrate to mammalian guanidino kinases remain elusive. Muscle creatine kinase is a dimer and disruption of the interface between subunits has been shown to give rise to destabilized monomers with slight residual activity; this low activity could, however, be due to a fraction of protein molecules present as dimer. CK monomer/monomer interface involves electrostatic interactions and increasing salt concentrations unfold and inactivate this enzyme. NaCl and guanidine hydrochloride show a synergistic unfolding effect and, whatever the respective concentrations of these compounds, inactivation is associated with a dissociation of the dimer. Using an interface mutant (W210Y), protein concentration dependence of the NaCl-induced unfolding profile indicates that the active dimer is in equilibrium with an inactive monomeric state. Although highly similar to muscle CK, horse shoe crab (Limulus polyphemus) arginine kinase (AK) is enzymatically active as a monomer. Indeed, high ionic strengths that can monomerize and inactivate CK, have no effect on AK enzymatic activity or on its structure as judged from intrinsic fluorescence data. Our results indicate that expression of muscle creatine kinase catalytic activity is dependent on its dimeric state which is required for a proper stabilization of the monomers. 相似文献
267.
Shimaa A.H. Abdel Monaim Yahya E. Jad Ayman El-Faham Beatriz G. de la Torre Fernando Albericio 《Bioorganic & medicinal chemistry》2018,26(10):2788-2796
It looks that a new era of antimicrobial peptides (AMPs) started with the discovery of teixobactin, which is a “head to side-chain” cyclodepsipeptide. It was isolated from a soil gram-negative b-proteobacteria by means of a revolutionary technique. Since there, several groups have developed synthetic strategies for efficient synthesis of this peptide and its analogues as well. Herein, all chemistries reported as well as the biological activity of the analogues are analyzed. Finally, some inputs regarding new trends for the next generation of analogues are discussed. 相似文献
268.
Christen Rune Stensvold Kasandra Ascuña-Durand Amal Chihi Salem Belkessa Özgür Kurt Ayman El-Badry Mark van der Giezen C. Graham Clark 《The Journal of eukaryotic microbiology》2023,70(2):e12949
Despite the species' wide distribution, studies of the genetic diversity within Entamoeba coli and Entamoeba hartmanni remain limited. In the present study, we provide further insight into the genetic diversity of both species based on analysis of partial nuclear small subunit ribosomal DNA sequences generated from human fecal DNAs from samples collected in Africa, South America, and Europe. Reinforcing the previous recognition that E. coli is a species complex, our data confirm the existence of the two subtypes, ST1 and ST2, previously identified plus, potentially, a new subtype, ST3. While ST1 appears to be genetically quite homogenous, ST2 shows a substantial degree of intrasubtype diversity. ST2 was more common in samples collected outside Europe, whereas ST1 showed no geographical restriction. The potentially novel subtype is represented to date exclusively by sequences from South American and African samples. In contrast to previous reports, our new data also indicate substantial variation in E. hartmanni that could also support the establishment of subtypes within this species. Here, however, no links were identified between subtype and geographical origin. 相似文献
269.
Casanova Manuel F. Shaban Mohamed Ghazal Mohammed El-Baz Ayman S. Casanova Emily L. Sokhadze Estate M. 《Applied psychophysiology and biofeedback》2021,46(2):161-173
Applied Psychophysiology and Biofeedback - Research suggest that in autism spectrum disorder (ASD) a disturbance in the coordinated interactions of neurons within local networks gives rise to... 相似文献
270.