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61.
A simple technique is presented for non-chromatographic purification of recombinant proteins expressed in Escherichia coli. This method is based on a reversibly precipitating, self-cleaving purification tag. The tag is made up of two components: an elastin-like polypeptide (ELP), which reversibly self-associates in high-salt buffers at temperatures above 30 degrees C; and an intein, which causes the ELP tag to self-cleave in response to a mild pH shift. Thus, a tripartite ELP-intein-target protein precursor can be purified by cycles of salt addition, heating and centrifugation. Once purified, intein-mediated self-cleavage, followed by precipitation of the cleaved ELP tag, allows easy and effective isolation of the pure, native target protein without the need for chromatographic separations. Recoveries of 50-100 mg of cleaved, native target protein per liter of shake-flask culture have been achieved for over a dozen proteins, typically in 8-24 h depending on specific process parameters. 相似文献
62.
Estarabadi Hanieh Atyabi Seyed Alireza Tavakkoli Sajjad Noormohammadi Zahra Gholami Mohamad Reza Ghiaseddin Ali Irani Shiva 《Molecular biology reports》2021,48(2):1323-1333
Molecular Biology Reports - In this paper, we studied the functional effects of cold atmospheric plasma (CAP) on the esophageal cancer cell line (KYSE-30) by direct and indirect treatment and... 相似文献
63.
Moradi Hamid Reza Hajali Vahid Khaksar Zabihollah Vafaee Farzaneh Forouzanfar Fatemeh Negah Sajad Sahab 《Molecular biology reports》2021,48(7):5647-5660
Molecular Biology Reports - Among different pathological mechanisms, neuronal loss and neurogenesis impairment in the hippocampus play important roles in cognitive decline in Alzheimer’s... 相似文献
64.
Leila Farahani Hasan Reza Etebarian Navazolah Sahebani Heshmatolah Aminian 《Archives Of Phytopathology And Plant Protection》2013,46(3):310-317
In this study, antagonistic yeast Candida membranifaciens was combined with different concentrations of silicon (Si; 0, 0.1, 0.3 and 0.5% wt/vol) to evaluate the control of blue mold of apple in storage at 20°C and 5°C. Preliminary studies showed that Si at 0.6% or above inhibited mycelial growth of pathogens significantly in vitro. In vitro studies showed that Si at 0.1% had lower effect on yeast growth. In vivo studies showed that combination of different concentrations of Si with C. membranifaciens improved the efficacy of yeast in control of disease better than Si and yeast alone (P < 0.05). Our result showed that the effective concentration of Si is varied based on pathogen isolates and temperature, so that the most effective concentration of Si was 0.5% for isolate P2 at 20°C and 0.5% and 0.1% for isolates P1 and P2 at 5°C. 相似文献
65.
66.
Moheb Ali Pourgholam Hossein Khara Reza Safari Mohammad Ali Yazdani Sadati Mohammad Sadegh Aramli 《Probiotics and antimicrobial proteins》2017,9(1):32-40
A feeding trial was conducted to investigate the effects of different levels of dietary Lactobacillus plantarum on hemato-immunological parameters and resistance against Streptococcus iniae infection in juvenile Siberian sturgeon Acipenser baerii. Fish (14.6 ± 2.3 g) were fed three experimental diets prepared by supplementing a basal diet with L. plantarum at different concentrations [1 × 107, 1 × 108 and 1 × 109 colony-forming units (cfu) g?1] and a control (non-supplemented basal) diet for 8 weeks. Innate immune responses (immunoglobulin (Ig), alternative complement activity (ACH50) and lysozyme activity) were significantly higher in fish fed the 1 × 108 and 1 × 109 cfu g?1 L. plantarum diet compared to the other groups (P < 0.05). Furthermore, fish fed on various levels of L. plantarum significantly showed higher red blood cell (RBC), hemoglobin (Hb), white blood cell (WBC) and monocyte compared to those of the control group (P < 0.05). At the end of the feeding experiment, some fish were challenged with S. iniae to quantify the level of disease resistance. The mortality after S. iniae challenge was decreased in fish fed a probiotic. These results indicated that dietary supplementation of L. plantarum improved immune response and disease resistance of Siberian sturgeon juvenile. 相似文献
67.
The specific and rapid formation of protein complexes is essential for diverse cellular processes such as remodeling of actin filaments in response to the interaction between Rho GTPases and the Wiskott-Aldrich syndrome proteins (WASp and N-WASp). Although Cdc42, TC10, and other members of the Rho family have been implicated in binding to and activating the WAS proteins, the exact nature of such a protein-protein recognition process has remained obscure. Here, we describe a mechanism that ensures rapid and selective long-range Cdc42-WASp recognition. The crystal structure of TC10, together with mutational and bioinformatic analyses, proved that the basic region of WASp and two unique glutamates in Cdc42 generate favorable electrostatic steering forces that control the accelerated WASp-Cdc42 association reaction. This process is a prerequisite for WASp activation and a critical step in temporal regulation and integration of WASp-mediated cellular responses. 相似文献
68.
Firouzeh Bordbar Mohammad Reza Rahiminejad Hojjatollah Saeidi Frank R. Blattner 《Plant Systematics and Evolution》2011,291(1-2):117-131
Cereal species of the grass tribe Triticeae are economically important and provide staple food for large parts of the human population. The Fertile Crescent of Southwest Asia harbors high genetic and morphological diversity of these species. In this study, we analyzed genetic diversity and phylogenetic relationships among D genome-bearing species of the wheat relatives of the genus Aegilops from Iran and adjacent areas using allelic diversity at 25 nuclear microsatellite loci, nuclear rDNA ITS, and chloroplast trnL-F sequences. Our analyses revealed high microsatellite diversity in Aegilops tauschii and the D genomes of Triticum aestivum and Ae. ventricosa, low genetic diversity in Ae. cylindrica, two different Ae. tauschii gene pools, and a close relationship among Ae. crassa, Ae. juvenalis, and Ae. vavilovii. In the latter species group, cloned sequences revealed high diversity at the ITS region, while in most other polyploids, homogenization of the ITS region towards one parental type seems to have taken place. The chloroplast genealogy of the trnL-F haplotypes showed close relationships within the D genome Aegilops species and T. aestivum, the presence of shared haplotypes in up to three species, and up to three different haplotypes within single species, and indicates chloroplast capture from an unidentified species in Ae. markgrafii. The ITS phylogeny revealed Triticum as monophyletic and Aegilops as monophyletic when Amblyopyrum muticum is included. 相似文献
69.
A total of 250 broilers in a completely randomized design selected to evaluate the effect of different levels of chromium (Cr) supplementation on performance, carcass traits and some blood parameters of heat-stressed broiler chicks. All birds were kept under heat stress temperature (33?±?3°C) and divided into five treatments groups. Each treatment consisted of five pens with 10 birds in each pen. The basal diets were supplemented with 0?ppb (control), 800?ppb Cr-L-Met (T(1)), 1,200?ppb Cr-L-Met (T(2)) or 800?ppb CrCl(3) (T(3)), and 1,200?ppb CrCl(3) (T(4)). The feed intake and body mass were measured at 10, 21, and 42?days of age. Blood samples were collected from two birds in each replicates to determine biological and hematological values at 28 and 42?days of age. There were no significant difference in mass gain and feed conversion of broilers that received Cr supplementations compared with controls. The serum glucose concentration decreased in broilers received organic chromium methionine supplements compared with other treatments groups. Slight but not significant increases were observed in serum high-density lipoprotein (HDL) concentration of treated groups than controls while the mean serum HDL concentration was significantly higher in T(2) group compared with control group. Serum low-density lipoprotein level decreased in broiler received organic Cr supplements (p?0.05). 相似文献
70.
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