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101.
Gallerano Daniela Devanaboyina Siva Charan Swoboda Ines Linhart Birgit Mittermann Irene Keller Walter Valenta Rudolf 《Amino acids》2011,40(3):981-989
HIV-1 virus infectivity factor (Vif) is one of the four accessory proteins that are characteristic of primate lentiviruses
and critically required for the infection of host cells. Vif plays a key role in replication and transmission of the virus
in non-permissive cells, such as primary T cells and macrophages. Using co-precipitation and co-fractionation techniques,
evidence has been provided that Vif interacts with a variety of host proteins, such as the cytidine deaminases APOBEC3G and
3F, the Cullin5/EloBC ubiquitin–ligase complex, Fyn and Hck tyrosine kinases, as well as with viral components, such as the
immature Gag precursor and viral RNA. We report on the expression, purification and molecular characterization of a folded
recombinant subtype C Vif. Vif was expressed in E. coli with a C-terminal hexahistidine tag and purified by nickel affinity chromatography. We obtained approximately 5 mg protein
per liter of bacterial culture, with a purity >95%. The expected molecular mass of 23.7 kDa was confirmed by mass spectrometry.
Although dynamic light scattering and small angle X-ray scattering measurements revealed the presence of high molecular weight
aggregates in the protein preparation, circular dichroism analysis showed that the protein contains mainly folded β-sheet
elements and exhibits remarkable thermal stability (T
m > 95°C). Recombinant Vif may be used as a tool to study its biological functions and tertiary structure, as well as for the
development of diagnostic, therapeutic and preventive strategies for HIV-1 infections. 相似文献
102.
Harish B. S. Raja Mamilla R. Charan Mahapatra Santanu Kar Uppuluri Kiran Babu 《International journal of peptide research and therapeutics》2021,27(1):197-208
International Journal of Peptide Research and Therapeutics - The significant role of proteases in the cancer progression exposed them as potential targets for drug discovery. Regulating protease... 相似文献
103.
104.
105.
Polycarpaea majumdariana , a new species allied to P. aurea (Wight) Dunn from the Tamil Nadu plains, is described and illustrated. 相似文献
106.
Gower DJ San Mauro D Giri V Bhatta G Govindappa V Kotharambath R Oommen OV Fatih FA Mackenzie-Dodds JA Nussbaum RA Biju SD Shouche YS Wilkinson M 《Molecular phylogenetics and evolution》2011,59(3):698-707
Together, Indian plus Seychelles caeciliid caecilian amphibians (Gymnophiona) constitute approximately 10% of the extant species of this order. A molecular phylogenetic analysis of all but one (or two) nominal species (16, in five genera) is presented based on mitochondrial (12S, 16S, cytb, cox1) and nuclear (RAG1) sequence data. Results strongly support monophyly of both Seychelles and peninsular Indian caeciliids, and their sister-group status. Within the Indian caeciliids, Indotyphlus and Gegeneophis are monophyletic sister genera. The phylogenetic position of Gegeneophis ramaswamii, Gegeneophis seshachari, and Gegeneophis carnosus are not well resolved, but all lie outside a well-supported clade of most northern Western Ghats Gegeneophis (madhavai, mhadeiensis, goaensis, danieli/nadkarnii). Most nominal species of Indian caeciliid are diagnosed by robust haplotype clades, though the systematics of G. carnosus-like forms in northern Kerala and southern Karnataka requires substantial further investigation. For the most part, Indian caeciliid species comprise narrowly distributed, allopatric taxa with low genetic diversity. Much greater geographic genetic diversity exists among populations referred to G. seshachari, such that some populations likely represent undescribed species. This, the first phylogenetic analysis of Indian caeciliids, generally provides additional support for recent increases in described species (eight since 1999), and a framework for ongoing taxonomic revision. 相似文献
107.
Singh N Charan S Sanjiv K Huang SH Hsiao YC Kuo CW Chien FC Lee TC Chen P 《Bioconjugate chemistry》2012,23(3):421-430
Here, we report the facile preparation of tunable magnetic Ni-doped near-infrared (NIR) quantum dots (MNIR-QDs) as an efficient probe for targeting, imaging, and cellular sorting applications. We synthesized the MNIR-QDs via a hot colloidal synthesis approach to yield monodisperse and tunable QDs. These hydrophobic QDs were structurally and compositionally characterized and further functionalized with amino-PEG and carboxyl-PEG to improve their biocompatibility. Since QDs are known to be toxic due to the presence of cadmium, we have evaluated the in vitro and in vivo toxicity of our surface-functionalized MNIR-QDs. Our results revealed that surface-functionalized MNIR-QDs did not exhibit significant toxicity at the concentrations used in the experiments and are therefore suitable for biological applications. For further in vitro applications, we covalently linked folic acid to the surface of amino-PEG-coated MNIR-QDs through NHS chemistry to target the folate receptors largely present in the HeLa cells to demonstrate the specific targeting and magnetic behavior of these MNIR-QDs. Improved specificity has been observed with treatment of HeLa cells with the folic acid-linked amino PEG-coated MNIR QDs (FA-PEG-MNIR-QDs) compared to the one without folic acid. Since the synthesized probe has magnetic property, we have also successfully demonstrated sorting between the cells which have taken up the probe with the use of a magnet. Our findings strongly suggest that these functionalized MNIR-QDs can be a potential probe for targeting, cellular sorting, and bioimaging applications. 相似文献
108.
Rakshita A Charan Gabriela Niizawa Hiroyuki Nakai Paula R Clemens 《Molecular medicine (Cambridge, Mass.)》2012,18(1):1527-1535
Duchenne muscular dystrophy (DMD) is a genetic muscle disease caused by the absence of a functional dystrophin protein. Lack of dystrophin protein disrupts the dystrophin-glycoprotein complex causing muscle membrane instability and degeneration. One of the secondary manifestations resulting from lack of functional dystrophin in muscle tissue is an increased level of cytokines that recruit inflammatory cells, leading to chronic upregulation of the nuclear factor (NF)-κB. Negative regulators of the classical NF-κB pathway improve muscle health in the mdx mouse model for DMD. We have previously shown in vitro that a negative regulator of the NF-κB pathway, A20, plays a role in muscle regeneration. Here, we show that overexpression of A20 by using a muscle-specific promoter delivered with an adeno-associated virus serotype 8 (AAV8) vector to the mdx mouse decreases activation of the NF-κB pathway in skeletal muscle. Recombinant A20 expression resulted in a reduction in number of fibers with centrally placed nuclei and a reduction in the number of T cells infiltrating muscle transduced with the AAV8–A20 vector. Taken together, we conclude that overexpression of A20 in mdx skeletal muscle provides improved muscle health by reduction of chronic inflammation and muscle degeneration. These results suggest A20 is a potential therapeutic target to ameliorate symptoms of DMD. 相似文献
109.
Kamarthapu V Rao KV Srinivas PN Reddy GB Reddy VD 《Biochimica et biophysica acta》2008,1784(12):1949-1958
S-adenosylmethionine (SAM) synthetase (EC 2.5.1.6) catalyzes the synthesis of S-adenosylmethionine using l-methionine and ATP as substrates. SAM synthetase gene (metE) from Bacillus subtilis was cloned and over-expressed, for the first time, in the heterologus host Escherichia coli as an active enzyme. Size-exclusion chromatography (SEC) revealed a molecular weight of ~180 kDa, suggesting that the enzyme is a homotetramer stabilized by non-covalent interactions. SAM synthetase exhibited optimal activity at pH 8.0 and 45 degrees C with the requirement of divalent cation Mg(2+), and stimulated by the monovalent cation K(+). The enzyme followed sequential mechanism with a V(max) of 0.362 micromol/min/mg, and a K(m) of 920 microM and 260 microM for ATP and l-methionine, respectively. The urea-induced unfolding equilibrium of the recombinant enzyme revealed a multistate process, comprising partially unfolded tetramer, structural dimer, structural monomer and completely unfolded monomer, as evidenced by intrinsic and extrinsic fluorescence, circular dichroism (CD) and SEC. Absence of trimer in the SEC implicates that the enzyme is a dimer of dimer. Concordance between results of SEC and enzyme activity in the presence of urea amply establishes that tetramer alone with intersubunit active site(s) exhibits enzyme activity. 相似文献
110.
NO-NSAIDs: Gastric-sparing nitric oxide-releasable prodrugs of non-steroidal anti-inflammatory drugs
Kumar V.S. Nemmani Sunil V. Mali Namdev Borhade Asif R. Pathan Manoj Karwa Venu Pamidiboina S.P. Senthilkumar Machhindra Gund Arun K. Jain Naveen K. Mangu Nauzer P. Dubash Dattatraya C. Desai Somesh Sharma Apparao Satyam 《Bioorganic & medicinal chemistry letters》2009,19(18):5297-5301
Recently, a new class of nitric-oxide-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) is being studied as ‘Safe NSAIDs’ because of their gastric-sparing properties. As an extension of our novel disulfide linker technology, we have designed, synthesized and evaluated novel NO-releasing NSAID prodrugs such as NO-Aspirin (1b–d) and NO-Diclofenac (2b–c). Although the amide-containing derivative 1d did not show any bioavailability, the remaining compounds have shown fair to excellent pharmacokinetic, anti-inflammatory and gastric-sparing properties. Among them, however, the NO-Diclofenac (2b) has shown the most promising pharmacokinetic, anti-inflammatory and NO-releasing properties and protected rats from NSAID-induced gastric damage which could be attributable to the beneficial effects of NO released from these prodrugs. 相似文献