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101.
A method for multiple sequence alignment with gaps   总被引:13,自引:0,他引:13  
A method that performs multiple sequence alignment by cyclical use of the standard pairwise Needleman-Wunsch algorithm is presented. The required central processor unit time is of the same order of magnitude as the standard Needleman-Wunsch pairwise implementation. Comparison with the one known case where the optimal multiple sequence alignment has been rigorously determined shows that in practice the proposed method finds the mathematically optimal solution. The more interesting question of the biological usefulness of such multiple sequence alignment over pairwise approaches is assessed using protein families whose X-ray structures are known. The two such cases studied, the subdomains of the ricin B-chain and the S-domains of virus coat proteins, have low pairwise similarity and thus fail to align correctly under standard pairwise sequence comparison. In both cases the multiple sequence alignment produced by the proposed technique, apart from minor deviations at loop regions, correctly predicts the true structural alignment. Thus, given many sequences of low pairwise similarity, the proposed multiple sequence method, can extract any familial similarity and so produce a sequence alignment consistent with the underlying structural homology.  相似文献   
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Biotechnology Letters - This review aims to summarize the current management of type 2 diabetes principles, including oral hypoglycemic agents, types of insulin administration, diet maintenance,...  相似文献   
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Vanillic acid (VA) is found in high concentrations in various plants and used as traditional medicine for various diseases. The aim of the existing study is to illustrate the protective effects of VA against benzo(a)pyrene (B(a)P)‐induced lung cancer in Swiss albino mice. B(a)P (50 mg/kg b.wt.) was given orally to induce lung cancer in mice. The body weight, tumor incidence, carcinoembryonic antigen (CEA), neuron‐specific enolase (NSE), and enzymatic/nonenzymatic antioxidants (superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase, and glutathione) were estimated. Further histochemical investigation through hematoxylin and eosin staining was also carried out. B(a)P administered groups showed increased levels of serum pathological markers CEA, NSE along with reduced final body weight as well as decreased tissue enzymatic and nonenzymatic antioxidants activities, whereas VA treatment (200mg/kg/b.wt) along with B(a)P showed significantly reverted the above changes, which proves as prominent anticancer effects in experimentally induced lung cancer. Overall, these results suggest that VA has an efficient preventive action against B(a)P‐induced lung cancer, and this is attributed to its free‐radical scavenging antioxidant activities.  相似文献   
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The diversity of culturable, aerobic and heterotrophic Bacillus and Bacillus-derived genera (BBDG) was investigated in various extreme environments (including thermal springs, cold deserts, mangroves, salt lakes, arid regions, salt pans and acidic soils) of India. Heat treatment followed by enrichment in different media led to a total of 893 bacterial isolates. Amplified ribosomal DNA restriction analysis (ARDRA) using three restriction enzymes AluI, MspI and HaeIII led to the clustering of these isolates into 12–74 groups for the different sites at 75 % similarity index, adding up to 559 groups. Phylogenetic analysis based on 16S rRNA gene sequencing led to the identification of 392 bacilli, grouped in two families, Bacillaceae (89.03 %) and Paenibacillaceae (10.97 %), and included 13 different genera with 75 distinct species. It was found that among the thirteen genera, nine (Bacillus, Halobacillus, Lysinibacillus, Oceanobacillus, Pontibacillus, Salinibacillus, Sediminibacillus, Thalassobacillus and Virgibacillus) belonged to Bacillaceae and four (Ammoniphilus, Aneurinibacillus, Brevibacillus and Paenibacillus) belonged to Paenibacillaceae. Novel isolates tolerant to low and high pH and temperature, salt and low moisture were identified. The major outcome of the present investigation was the identification of niche-specific species and also the ubiquitous presence of selected species of BBDG, which illustrate the diversity and pervasive nature of BBDG in extreme environments.  相似文献   
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In this paper, a highly sensitive, reagentless, electrochemical strategy is reported for the detection of a cancer biomarker-Vascular Endothelial Growth Factor (VEGF). Disc shaped carbon fiber microelectrodes were used as the immunosensor platform. Ferrocene monocarboxylic acid labeled anti-VEGF was covalently immobilized on the microelectrode surface using a Jeffamine cross-linker. The formation of immunocomplexes leads to a decrease in the electrochemical signal of ferrocene monocarboxylic acid owing to increased spatial blocking of microelectrode surface. These signal changes enable quantitative detection of VEGF in solution. Voltammetric measurements were conducted to evaluate the interfacial immunoreactions and to quantitatively detect VEGF biomarker. The proposed immunosensing strategy allows a rapid and sensitive means of VEGF analysis with a limit of detection of about 38 pg/mL. This opens up the possibility of employing these electrodes for various single cell analysis and clinical applications. Further, experimental conditions such as concentration of the immobilized antibodies and incubation period were optimized. Following this, the stability and specificity of the immunosensors were also evaluated.  相似文献   
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Bioinformatics and computational biology, along with the related fields of genomics, proteomics, functional genomics and systems biology are new wave scientific disciplines that harness composite computational power across networks to advance biological knowledge at the most basic level and to direct traditional laboratory-based research efforts in the biomedical sciences. 'Fostering the growth of bioinformatics and allied disciplines in the Asia-Pacific region' is the motto of the first regional bioinformatics society, the Asia-Pacific Bioinformatics Network (APBioNet). APBioNet addresses the issues of hardware, software, databases and networks pertaining to bioinformatics, with the additional layer of pertinent education, training and research. Recent milestones achieved include hosting an international bioinformatics symposium in Asia and setting up large-scale regional grid-computing projects.  相似文献   
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