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941.
Zohreh Moradi Ali Reza Rezvani Meissam Noroozifar 《Journal of biomolecular structure & dynamics》2018,36(3):779-794
In order to evaluate biological potential of a novel synthesized complex [Nd(dmp)2Cl3.OH2] where dmp is 29-dimethyl 110-phenanthroline, the DNA-binding, cleavage, BSA binding, and antimicrobial activity properties of the complex are investigated by multispectroscopic techniques study in physiological buffer (pH 7.2).The intrinsic binding constant (Kb) for interaction of Nd(III) complex and FS–DNA is calculated by UV–Vis (Kb = 2.7 ± 0.07 × 105) and fluorescence spectroscopy (Kb = 1.13 ± 0.03 × 105). The Stern–Volmer constant (KSV), thermodynamic parameters including free energy change (ΔG°), enthalpy change (?H°), and entropy change (?S°), are calculated by fluorescent data and Vant’ Hoff equation. The experimental results show that the complex can bind to FS–DNA and the major binding mode is groove binding. Meanwhile, the interaction of Nd(III) complex with protein, bovine serum albumin (BSA), has also been studied by using absorption and emission spectroscopic tools. The experimental results show that the complex exhibits good binding propensity to BSA. The positive ΔH° and ?S° values indicate that the hydrophobic interaction is main force in the binding of the Nd(III) complex to BSA, and the complex can quench the intrinsic fluorescence of BSA remarkably through a static quenching process. Also, DNA cleavage was investigated by agarose gel electrophoresis that according to the results cleavage of DNA increased with increasing of concentration of the complex. Antimicrobial screening test gives good results in the presence of Nd(III) complex system. 相似文献
942.
943.
The binding of the nonintercalating dye berenil to the 70S ribosome of Escherichia coli has been demonstrated by spectrophotometric measurements and gel filtration through Biogel P100 column. The berenil spectrum is gradually shifted towards the red region with the increasing amount of ribosome added, the isosbestic point being at 375 nm. There is positive cooperativity in the binding of berenil to the ribosome as demonstrated by the equilibrium dialysis. On binding with berenil, the ribosome is degraded faster by RNase I especially at low Mg++ concentration and its capacity to inhibit RNase I catalysed hydrolysis of ribopolymers is decreased. These indicate the unfolding of the structure of the ribosome. 相似文献
944.
Mohammad Javad Motamedi Jafar Amani Shahla Shahsavandi Ali Hatef Salmanian 《International journal of peptide research and therapeutics》2014,20(2):179-194
Application of molecular biology techniques to the production of new vaccines against different strains of the Newcastle disease virus (NDV) has been the subject of recent research reports. Development of improved techniques for genome sequencing has led to the recognition of protective mechanisms and the identification of possible candidate antigens. Such procedures could generate meaningful results regarding the virulence determinants of NDV. This study proposed an in silico approach by assembling potential and conserved epitopic regions of hemagglutinin–neuraminidase (HN) and fusion (F) glycoproteins of NDV to induce multiepitopic responses against the virus. Epitope predictions showed that the hypothetical synthetic construct could induce immature B and T cell epitopes that expect a high immune response because of their location in four distinct parts of the construct, namely the head, stalk and the heptad repeated regions known as the HRA and HRB domains. Most regions of the chimeric construct were found to have high antigenic propensity and surface accessibility, which further confirmed the strategy for selection of precise continuous and discontinuous epitopes of HN and F antigens. Thermodynamic folding of mRNA structures revealed correct folding of the RNA construct, indicating good stability of the mRNA to increase the efficiency of translation in the target host. The three-dimensional structure of the native HN-F chimeric protein was successfully generated and validated as a proper model which may define reliability, structural quality and conformation. 相似文献
945.
Osama M. Abo‐Salem Gamaleldin I. Harisa Tarek M. Ali El‐Sayed M. El‐Sayed Fatma M. Abou‐Elnour 《Journal of biochemical and molecular toxicology》2014,28(6):263-270
Heart failure (HF) is one of diabetic complications. This work was designed to investigate the possible modulatory effect of curcumin against streptozotocin‐induced diabetes and consequently HF in rats. Rats were divided into control, vehicle‐treated, curcumin‐treated, diabetic‐untreated, diabetic curcumin–treated, and diabetic glibenclamide–treated groups. Animal treatment was started 5 days after induction of diabetes and extended for 6 weeks. Diabetic rats showed significant increase in serum glucose, triglycerides, total cholesterol, low‐density lipoprotein‐cholesterol, very low density lipoprotein‐cholesterol, nitric oxide, lactate dehydrogenase, cardiac malondialdehyde, plasma levels of interleukin‐6, and tumor necrosis factor‐alpha, and also showed marked decrease in serum high‐density lipoprotein‐cholesterol, cardiac reduced glutathione, and cardiac antioxidant enzymes (catalase, superoxide dismutase, and glutathione‐S‐transferase). However, curcumin or glibenclamide treatment significantly mitigated such changes. In conclusion, curcumin has a beneficial therapeutic effect in diabetes‐induced HF, an effect that might be attributable to its antioxidant and suppressive activity on cytokines. 相似文献
946.
Pseudomonas amygdali pv. lachrymans is currently of important plant pathogenic bacteria that causes cucumber angular leaf spot worldwide. The pathogen has been studied for its roles in pathogenicity and plant inheritance resistance. To further delineate traits critical to virulence, invasion and survival in the phyllosphere, we reported the first complete genome of P. amygdali pv. lachrymans NM002. Analysis of the whole genome in comparison with three closely-related representative pathovars of P. syringae identified the conservation of virulence genes, including flagella and chemotaxis, quorum-sensing systems, two-component systems, and lipopolysaccharide and antiphagocytosis. It also revealed differences of invasion determinants, such as type III effectors, phytotoxin (coronatine, syringomycin and phaseolotoxin) and cell wall-degrading enzyme, which may contribute to infectivity. The aim of this study was to derive genomic information that would reveal the probable molecular mechanisms underlying the virulence, infectivity and provide a better understanding of the pathogenesis of the P. syringae pathovars. 相似文献
947.
948.
949.
Hongchen Yan Junjie Xu Ilyas Ali Wei Zhang Ming Jiang Guiping Li Yong Teng Guangxun Zhu Yafei Cai 《Cell proliferation》2022,55(5)
Purpose and MaterialsCDK5RAP3 (CDK5 regulatory subunit associated protein 3) was originally identified as a binding protein of CDK5. It is a crucial gene controlling biological functions, such as cell proliferation, apoptosis, invasion, and metastasis. Although previous studies have also shown that CDK5RAP3 is involved in a variety of signalling pathways, however, the mechanism of CDK5RAP3 remains largely undefined. This study utilized MEFs from conditional knockout mice to inhibit CDK5RAP3 and knockdown CDK5RAP3 in MCF7 to explore the role of CDK5RAP3 in cell growth, mitosis, and cell death.ResultsCDK5RAP3 was found to be widely distributed throughout the centrosome, spindle, and endoplasmic reticulum, indicating that it is involved in regulating a variety of cellular activities. CDK5RAP3 deficiency resulted in instability of cell growth. CDK5RAP3 deficiency partly blocks the cell cycle in G2/M by downregulating CDK1 (Cyclin‐dependent kinase 1) and CCNB1 (Cyclin B1) expression levels. The cell proliferation rate was decreased, thereby slowing down the cell growth rate. Furthermore, the results showed that CDK5RAP3 interacts with RPL26 (ribosome protein L26) to regulate the mTOR pathway. CDK5RAP3 and RPL26 deficiency inhibited mTOR/p‐mTOR protein and induce autophagy, resulting in an upregulation of the percentage of apoptosis, and the upregulated percentage of apoptosis also slowed cell growth.ConclusionsOur experiments show that CDK5RAP3 interacts with RPL26 and maintains the stability of cell growth. It shows that CDK5RAP3 plays an important role in cell growth and can be used as the target of gene medicine.In normal, CDK5RAP3 is distributed in the centrosome, spindle and endoplasmic reticulum, the cells undergoes the growth and proliferation. However, when CDK5RAP3 is deficient, the cell cycle is blocked in G2/M and cell proliferation slows down, and the partial cycle block does not cause apoptosis. Additionally, CDK5RAP3 distributed in the endoplasmic reticulum combined with the deficiency of RPL26 will inhibit the mTOR pathway, aggravate autophagy and trigger apoptosis. 相似文献
950.
Mohamed S. Elshikh Mohammad Ajmal Ali Fahad Al-Hemaid Soo Yong Kim Meena Elangbam Arun Bahadur Gurung Prasanjit Mukherjee Mohamed El-Zaidy Joongku Lee 《Saudi Journal of Biological Sciences》2022,29(3):1313-1321
The enhanced understanding of chloroplast genomics would facilitate various biotechnology applications; however, the chloroplast (cp) genome / plastome characteristics of plants like Fagonia indica Burm.f. (family Zygophyllaceae), which have the capability to grow in extremely hot sand desert, have been rarely understood. The de novo genome sequence of F. indica using the Illumina high-throughput sequencing technology determined 128,379 bp long cp genome, encode 115 unique coding genes. The present study added the evidence of the loss of a copy of the IR in the cp genome of the taxa capable to grow in the hot sand desert. The maximum likelihood analysis revealed two distinct sub-clades i.e. Krameriaceae and Zygophyllaceae of the order Zygophyllales, nested within fabids. 相似文献