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Background
A large number of microsatellites have been extensively used to comprehend the genetic diversity of different global groups. This paper entails polymorphism at 15 STR in four predominant and endogamous populations representing Karnataka, located on the southwest coast of India. The populations residing in this region are believed to have received gene flow from south Indian populations and world migrants, hence, we carried out a detailed study on populations inhabiting this region to understand their genetic structure, diversity related to geography and linguistic affiliation and relatedness to other Indian and global migrant populations. 相似文献53.
Govinal Badiger Bhaskara Min May Wong Paul E. Verslues 《Plant, cell & environment》2019,42(10):2913-2930
Protein phosphorylation is a key signalling mechanism and has myriad effects on protein function. Phosphorylation by protein kinases can be reversed by protein phosphatases, thus allowing dynamic control of protein phosphorylation. Although this may suggest a straightforward kinase–phosphatase relationship, plant genomes contain five times more kinases than phosphatases. Here, we examine phospho‐signalling from a protein phosphatase centred perspective and ask how relatively few phosphatases regulate many phosphorylation sites. The most abundant class of plant phosphatases, the protein phosphatase 2Cs (PP2Cs), is surrounded by a web of regulation including inhibitor and activator proteins as well as posttranslational modifications that regulate phosphatase activity, control phosphatase stability, or determine the subcellular locations where the phosphatase is present and active. These mechanisms are best established for the Clade A PP2Cs, which are key components of stress and abscisic acid signalling. We also describe other PP2C clades and illustrate how these phosphatases are highly regulated and involved in a wide range of physiological functions. Together, these examples of multiple layers of phosphatase regulation help explain the unbalanced kinase–phosphatase ratio. Continued use of phosphoproteomics to examine phosphatase targets and phosphatase–kinase relationships will be important for deeper understanding of phosphoproteome regulation. 相似文献
54.
Sae2 is an endonuclease that processes hairpin DNA cooperatively with the Mre11/Rad50/Xrs2 complex 总被引:5,自引:0,他引:5
Mre11/Rad50 complexes in all organisms function in the repair of DNA double-strand breaks. In budding yeast, genetic evidence suggests that the Sae2 protein is essential for the processing of hairpin DNA intermediates and meiotic double-strand breaks by Mre11/Rad50 complexes, but the biochemical basis of this functional relationship is not known. Here we demonstrate that recombinant Sae2 binds DNA and exhibits endonuclease activity on single-stranded DNA independently of Mre11/Rad50 complexes, but hairpin DNA structures are cleaved cooperatively in the presence of Mre11/Rad50 or Mre11/Rad50/Xrs2. Hairpin structures are not processed at the tip by Sae2 but rather at single-stranded DNA regions adjacent to the hairpin. Truncation and missense mutants of Sae2 inactivate this endonuclease activity in vitro and fail to complement Deltasae2 strains in vivo for meiosis and recombination involving hairpin intermediates, suggesting that the catalytic activities of Sae2 are important for its biological functions. 相似文献
55.
Ravichandran Mahalingam Harish Ravivarapu Sanjeev Redkar Xiaoling Li Bhaskara R. Jasti 《AAPS PharmSciTech》2007,8(3):E28-E33
Delivery of 5-aza-2′-deoxycytidine (decitabine) across porcine buccal mucosa was evaluated as an alternative to the complex
intravenous infusion regimen currently used to administer the drug. A reproducible high-performance liquid chromatography
method was developed and optimized for the quantitative determination of this drug. Decitabine showed a concentration-dependent
passive diffusion process across porcine buccal mucosa. An increase in the ionic strength of the phosphate buffer from 100
to 400 mM decreased the flux from 3.57±0.65 to 1.89±0.61 μg/h/cm2. Trihydroxy bile salts significantly enhanced the flux of decitabine at a 100 mM concentration (P>.05). The steady-state flux of decitabine in the presence of 100 mM of sodium taurocholate and sodium glycocholate was 52.65±9.48
and 85.22±7.61 μg/cm2/h, respectively. Two dihydroxy bile salts, sodium deoxytaurocholate and sodium deoxyglycocholate, showed better enhancement
effect than did trihydroxy bile salts. A 38-fold enhancement in flux was achieved with 10 mM of sodium deoxyglycocholate.
Published: July 13, 2007 相似文献
56.
Phanidhara R. Kotamraj Xiaoling Li Bhaskara Jasti Wade A. Russu 《Bioorganic & medicinal chemistry letters》2009,19(20):5877-5879
A model peptide–drug conjugate designed upon a β-hairpin peptide with the α4β1 integrin recognition sequence LDV appended to the N-terminus and a fluorescent model drug appended to the C-terminus. This model recognizes and binds to α4β1 expressing cells and displays an enhanced rate of enzyme catalyzed hydrolytic model drug release in the presence of the cells compared to the rate in the absence of cells. The present work suggests that peptide–drug conjugate conformation change due to receptor binding may be a viable approach to targeted drug release. 相似文献
57.
S. Indu Senthil T. Kumar Sudhir Thakurela Mansi Gupta Ramachandra M. Bhaskara C. Ramakrishnan Raghavan Varadarajan 《Proteins》2010,78(5):1228-1242
To understand structural and thermodynamic features of disulfides within an α‐helix, a non‐redundant dataset comprising of 5025 polypeptide chains containing 2311 disulfides was examined. Thirty‐five examples were found of intrahelical disulfides involving a CXXC motif between the N‐Cap and third helical positions. GLY and PRO were the most common amino acids at positions 1 and 2, respectively. The N‐Cap residue for disulfide bonded CXXC motifs had average (?,ψ) values of (?112 ± 25.2°, 106 ± 25.4°). To further explore conformational requirements for intrahelical disulfides, CYS pairs were introduced at positions N‐Cap‐3; 1,4; 7,10 in two helices of an Escherichia coli thioredoxin mutant lacking its active site disulfide (nSS Trx). In both helices, disulfides formed spontaneously during purification only at positions N‐Cap‐3. Mutant stabilities were characterized by chemical denaturation studies (in both oxidized and reduced states) and differential scanning calorimetry (oxidized state only). All oxidized as well as reduced mutants were destabilized relative to nSS Trx. All mutants were redox active, but showed decreased activity relative to wild‐type thioredoxin. Such engineered disulfides can be used to probe helix start sites in proteins of unknown structure and to introduce redox activity into proteins. Conversely, a protein with CYS residues at positions N‐Cap and 3 of an α‐helix is likely to have redox activity. Proteins 2010. © 2009 Wiley‐Liss, Inc. 相似文献
58.
A method for the measurement of water that is strongly held by lysozyme is described. This water is slowly removed by vaccum drying of lyophilized and can be titrated with the Karl Fischer reagent. Drying curves were obtained by mechanical pumping (moderate vacuum) and diffusion pumping (high vacuum) at 20°, 10°, 0°, ?10° and ?20°C. About 23 water molecules per lysozyme molecule are at least moderately held by the protein. These water molecules fall into several classes. Three to four of them are quite strongly held and may correspond to the three buried water molecules observed in the x-ray analysis of lysozyme structure. The presence of tri-N-acetylglycosamine in the lysozyme active cleft has no effect on drying at 0°C. The method shows promise of being generally applicable to the measurement of small amounts of water which are strongly held by biological structures. 相似文献
59.
Abjal Pasha Shaik Abbas H Alsaeed S Kiranmayee VK Bammidi Asma Sultana 《Bioinformation》2013,9(1):29-36
Cubilin, (CUBN; also known as intrinsic factor-cobalamin receptor [Homo sapiens Entrez Pubmed ref ; NM_001081.3;
GI: 119606627]), located in the epithelium of intestine and kidney acts as a receptor for intrinsic factor – vitamin B12 complexes.
Mutations in CUBN may play a role in autosomal recessive megaloblastic anemia. The current study investigated the possible role
of CUBN in evolution using phylogenetic testing. A total of 588 BLAST hits were found for the cubilin query sequence and these
hits showed putative conserved domain, CUB superfamily (as on 27th Nov 2012). A first-pass phylogenetic tree was constructed to
identify the taxa which most often contained the CUBN sequences. Following this, we narrowed down the search by manually
deleting sequences which were not CUBN. A repeat phylogenetic analysis of 25 taxa was performed using PhyML, RAxML and
TreeDyn softwares to confirm that CUBN is a conserved protein emphasizing its importance as an extracellular domain and being
present in proteins mostly known to be involved in development in many chordate taxa but not found in prokaryotes, plants and
yeast.. No horizontal gene transfers have been found between different taxa. NG_008967.1相似文献
60.
VK Satya R Radhajeyalakshmi K Kavitha V Paranidharan R Bhaskaran 《Archives Of Phytopathology And Plant Protection》2013,46(3):185-192
The fungitoxic effect of various medicinal plants belonging to different families was evaluated in vitro on Rhizoctonia solani, the rice sheath blight pathogen. Of the various plant extracts, the leaf extract of zimmu (Allium cepa × Allium sativum) showed the maximum antifungal activity against R. solani and recorded an inhibition zone of 12?mm. The leaf extract of zimmu was also effective in inhibiting the growth of other agronomically important fungal and bacterial pathogens viz., Aspergillus flavus, Curvularia lunata, Alternaria solani, Xanthomonas oryzae pv. oryzae, Xanthomonas campestris pv. malvacearum and Xanthomonas axonopodis pv. citri. The antimicrobial compound was dissoluble in methanol and the methanolic extract showed the absorption maxima at 210?nm and 230?nm. Phenolic compounds were present in greater amounts in methanol extract of zimmu. TLC analysis showed the appearance of two blue spots at R f ?=?0.65 and R f ?=?0.90. The compounds eluted at R f ?=?0.65 and R f ?=?0.90 by preparative TLC exhibited strong antifungal activity against R. solani. 相似文献