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1.
R Lawson 《BioTechniques》1990,8(6):680-683
PaperChase is a computer program which provides an efficient interface to the National Library of Medicine's MEDLINE database of references to the biomedical literature. The database includes references (citations) and abstracts compiled from Index Medicus, the International Nursing Index and the Index to Dental Literature. PaperChase may be accessed using any computer terminal or personal computer with modem. No special knowledge of computers or biomedical terms is necessary. Simple menus enable the novice to search the biomedical literature without training. A command language speeds searching for the experienced user. PaperChase does not require the user to know the database's indexing terminology, called Medical Subject Headings. Everyday language may be used and PaperChase will translate, or "map", the user's search term into the required Medical Subject Heading. PaperChase monitors a search in progress and suggests additional Medical Subject Headings which can be used to broaden or narrow a search. The searcher can order a full-text photocopy of any reference found in PaperChase. Support documentation and a subscriber newsletter are provided at no charge. Trained search specialists are available to offer assistance and to answer questions.  相似文献   

2.
Channelrhodopsins are microbial-type rhodopsins that function as light-gated cation channels. Understanding how the detailed architecture of the protein governs its dynamics and specificity for ions is important, because it has the potential to assist in designing site-directed channelrhodopsin mutants for specific neurobiology applications. Here we use bioinformatics methods to derive accurate alignments of channelrhodopsin sequences, assess the sequence conservation patterns and find conserved motifs in channelrhodopsins, and use homology modeling to construct three-dimensional structural models of channelrhodopsins. The analyses reveal that helices C and D of channelrhodopsins contain Cys, Ser, and Thr groups that can engage in both intra- and inter-helical hydrogen bonds. We propose that these polar groups participate in inter-helical hydrogen-bonding clusters important for the protein conformational dynamics and for the local water interactions. This article is part of a Special Issue entitled: Retinal Proteins — You can teach an old dog new tricks.  相似文献   

3.
Microsatellites are ubiquitous short tandem repeats found in all known genomes and are known to play a very important role in various studies and fields including DNA fingerprinting, paternity studies, evolutionary studies, virulence and adaptation of certain bacteria and viruses etc. Due to the sequencing of several genomes and the availability of enormous amounts of sequence data during the past few years, computational studies of microsatellites are of interest for many researchers. In this context, we developed a software tool called Imperfect Microsatellite Extractor (IMEx), to extract perfect, imperfect and compound microsatellites from genome sequences along with their complete statistics. Recently we developed a user-friendly graphical-interface using JAVA for IMEx to be used as a stand-alone software named G-IMEx. G-IMEx takes a nucleotide sequence as an input and the results are produced in both html and text formats. The Linux version of G-IMEx can be downloaded for free from http://www.cdfd.org.in/imex.  相似文献   

4.
Current standardization initiatives have greatly contributed to share the information derived by proteomics experiments. One of these initiatives is the XML-based repository PRIDE (PRoteomics IDEntification database), although an XML-based document does not appear to present a user-friendly view at the first glance. PRIDEViewer is a novel Java-based application that presents the information available in a PRIDE XML file in a user-friendly manner, facilitating the interaction among end users as well as the understanding and evaluation of the compiled information. PRIDEViewer is freely available at: http://proteo.cnb.csic.es/prideviewer/.  相似文献   

5.
Novel and improved computational tools are required to transform large-scale proteomics data into valuable information of biological relevance. To this end, we developed ProteoConnections, a bioinformatics platform tailored to address the pressing needs of proteomics analyses. The primary focus of this platform is to organize peptide and protein identifications, evaluate the quality of the acquired data set, profile abundance changes, and accelerate data interpretation. Peptide and protein identifications are stored into a relational database to facilitate data mining and to evaluate the quality of data sets using graphical reports. We integrated databases of known PTMs and other bioinformatics tools to facilitate the analysis of phosphoproteomics data sets and to provide insights for subsequent biological validation experiments. Phosphorylation sites are also annotated according to kinase consensus motifs, contextual environment, protein domains, binding motifs, and evolutionary conservation across different species. The practical application of ProteoConnections is further demonstrated for the analysis of the phosphoproteomics data sets from rat intestinal IEC-6 cells where we identified 9615 phosphorylation sites on 2108 phosphoproteins. Combined proteomics and bioinformatics analyses revealed valuable biological insights on the regulation of phosphoprotein functions via the introduction of new binding sites on scaffold proteins or the modulation of protein-protein, protein-DNA, or protein-RNA interactions. Quantitative proteomics data can be integrated into ProteoConnections to determine the changes in protein phosphorylation under different cell stimulation conditions or kinase inhibitors, as demonstrated here for the MEK inhibitor PD184352.  相似文献   

6.
This paper presents a simple program for interactive searchingfor nucleotide sequences that may code for the helix—turn—helix,zinc finger or leucine zipper motifs in proteins. The helix—turn—helixmotifs are predicted using the recently published method ofDodd and Egan, while zinc fingers and leucine zippers are searchedfor by our original methods. DNABIND is shown to detect allfour known helix—turn—helix motifs in bacteriophagelambda genes and both zinc fingers of the adrl gene of yeast.  相似文献   

7.
We describe a computer program (Metal Search) that helps design tetrahedrally coordinated metal binding sites in proteins of known structure. The program takes as input the backbone coordinates of a protein and outputs lists of four residues that might form tetrahedral sites if wild-type amino acids were replaced by cysteine or histidine. The program also outputs the side chain dihedral angles of the amino acids and the coordinates of the predicted metal ion. The only function evaluated by Metal Search is the ability of side chains to meet simple geometric criteria for formation of a tetrahedral site, but these criteria are sufficient to produce a manageably small list that can then be evaluated by other means. The program has been used in the introduction of zinc binding sites in the designed four-helix bundle protein α 4 and in the B1 domain of streptococcal protein G, and in both cases the tetrahedral coordination of a bound metal ion has been confirmed1 (Klemba, M., Gardner, K. H., Marino, S., Clarke, N. D., and Regan, L., Nature: Structural Biology 2:368–373, 1995). © 1995 Wiley-Liss, Inc.  相似文献   

8.
Protein-protein ligand is one of the most detection methods used in Nano biosensors. Based on the advantage of specific docking between two special 3D structures, they have become a potent candidate in bioanalysis and Nanodiagnostic tools. These tools lease users to do a simple, fast, cost-effective, sensitive, and specific detection of molecular biomarkers in real samples. Recent advantages of using protein-protein ligand Nano-biosensors application is remarkable due to its special docking that refers to each protein unique 3D conformation. However, it challenges different problems such as low rate of docking and hard process for fixation on the basic layer. These challenges make developers to optimize the structure and functions of proteins. The process has different Nano scale calculation that could be done with algorithms and solutions are available as bioinformatics tools. This article aimed to have a short overview of the abilities of bioinformatics tools for modeling and optimization of physiochemical features of proteins in Nano scale.  相似文献   

9.
BlastAlign uses NCBI blastn to build a multiple nucleotide alignment and is intended for use with sequences that have large indels or are otherwise difficult to align globally. The program builds a matrix representing regions of homology along the sequences, from which it selects the 'most representative' sequence and then extracts the blastn query-anchored multiple alignment for this sequence. The matrix is printed and allows subgroups to be identified visually and an option allows other sequences to be used as the 'most representative'. The program contains elements of both Perl and Python and will run on UNIX (including Mac OSX) and DOS. An additional Perl program BlastAlignP uses tblastn to align nucleotide sequences to a single amino acid sequence, thus allowing an open reading frame to be maintained in the resulting multiple alignment. AVAILABILITY: It is freely available at http://www.bio.ic.ac.uk/research/belshaw/BlastAlign.tar and at http://evolve.zoo.ox.ac.uk/software/blastalign.  相似文献   

10.
This work presents a novel database search engine – MLibrary – designed to assist the user in the detection and identification of androgenic anabolic steroids (AAS) and its metabolites by matrix assisted laser desorption/ionization (MALDI) and mass spectrometry-based strategies. The detection of the AAS in the samples was accomplished by searching (i) the mass spectrometric (MS) spectra against the library developed to identify possible positives and (ii) by comparison of the tandem mass spectrometric (MS/MS) spectra produced after fragmentation of the possible positives with a complete set of spectra that have previously been assigned to the software. The urinary screening for anabolic agents plays a major role in anti-doping laboratories as they represent the most abused drug class in sports. With the help of the MLibrary software application, the use of MALDI techniques for doping control is simplified and the time for evaluation and interpretation of the results is reduced. To do so, the search engine takes as input several MALDI-TOF–MS and MALDI-TOF–MS/MS spectra. It aids the researcher in an automatic mode by identifying possible positives in a single MS analysis and then confirming their presence in tandem MS analysis by comparing the experimental tandem mass spectrometric data with the database. Furthermore, the search engine can, potentially, be further expanded to other compounds in addition to AASs. The applicability of the MLibrary tool is shown through the analysis of spiked urine samples.  相似文献   

11.
Carbon distribution is responsible for stability and structure of proteins. Arrangement of carbon along the protein sequence is depends on how the amino acids are organized and is guided by mRNAs. An atomic level revision is important for understanding these codes. This will ultimately help in identification of disorders and suggest mutations. For this purpose a carbon distribution analysis program has been developed. This program captures the hydrophobic / hydrophilic / disordered regions in a protein. The program gives accurate results. The calculations are precise and sensitive to single amino acid resolution. This program is to help in mutational studies leading to protein stabilisation.  相似文献   

12.
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14.
This review of sequence database searching aims to set out current practice in the area, in order to give practical guidelines to the experimental biologist. It describes the basic principles behind the programs and enumerates the range of databases available in the public domain. Of these, the most important are the equivalent DNA databases European Molecular Biology Laboratory (EMBL), GenBank and DNA Databank of Japan (DDBJ), and the protein databases Swiss-Prot and TrEMBL. The commonly used BLAST and FASTA algorithms are described in detail and alternative approaches mentioned briefly. Scoring matrices used to compare amino acid types during protein database searches are compared, with an emphasis on the PAM and BLOSUM series of observed substitution matrices.  相似文献   

15.
BackgroundMassive sequencing of genes from different environments has evolved metagenomics as central to enhancing the understanding of the wide diversity of micro-organisms and their roles in driving ecological processes. Reduced cost and high throughput sequencing has made large-scale projects achievable to a wider group of researchers, though complete metagenome sequencing is still a daunting task in terms of sequencing as well as the downstream bioinformatics analyses. Alternative approaches such as targeted amplicon sequencing requires custom PCR primer generation, and is not scalable to thousands of genes or gene families.ResultsIn this study, we are presenting a web-based tool called MetCap that circumvents the limitations of amplicon sequencing of multiple genes by designing probes that are suitable for large-scale targeted metagenomics sequencing studies. MetCap provides a novel approach to target thousands of genes and genomic regions that could be used in targeted metagenomics studies. Automatic analysis of user-defined sequences is performed, and probes specifically designed for metagenome studies are generated. To illustrate the advantage of a targeted metagenome approach, we have generated more than 300,000 probes that match more than 400,000 publicly available sequences related to carbon degradation, and used these probes for target sequencing in a soil metagenome study. The results show high enrichment of target genes and a successful capturing of the majority of gene families. MetCap is freely available to users from: http://soilecology.biol.lu.se/metcap/.ConclusionMetCap is facilitating probe-based target enrichment as an easy and efficient alternative tool compared to complex primer-based enrichment for large-scale investigations of metagenomes. Our results have shown efficient large-scale target enrichment through MetCap-designed probes for a soil metagenome. The web service is suitable for any targeted metagenomics project that aims to study several genes simultaneously. The novel bioinformatics approach taken by the web service will enable researchers in microbial ecology to tap into the vast diversity of microbial communities using targeted metagenomics as a cost-effective alternative to whole metagenome sequencing.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-015-0501-8) contains supplementary material, which is available to authorized users.  相似文献   

16.
Here, we present an antigen selection strategy based on a whole-genome bioinformatics approach, which is facilitated by an interactive visualization tool displaying protein features from both public resources and in-house generated data. The web-based bioinformatics platform has been designed for selection of multiple, non-overlapping recombinant protein epitope signature tags by display of predicted information relevant for antigens, including domain- and epitope sized sequence similarities to other proteins, transmembrane regions and signal peptides. The visualization tool also displays shared and exclusive protein regions for genes with multiple splice variants. A genome-wide analysis demonstrates that antigens for approximately 80% of the human protein-coding genes can be selected with this strategy.  相似文献   

17.
Haidar JN  Yuan QA  Zeng L  Snavely M  Luna X  Zhang H  Zhu W  Ludwig DL  Zhu Z 《Proteins》2012,80(3):896-912
Antibody (Ab) humanization is crucial to generate clinically relevant biologics from hybridoma-derived monoclonal antibodies (mAbs). In this study, we integrated antibody structural information from the Protein Data Bank with known back-to-mouse mutational data to build a universal consensus of framework positions (10 heavy and 7 light) critical for the preservation of the functional conformation of the Complimentarity Determining Region of antibodies. On the basis of FR consensus, we describe here a universal combinatorial library suitable for humanizing exogenous antibodies by CDR-grafting. The six CDRs of the murine anti-human EGFR Fab M225 were grafted onto a distinct (low FR sequence similarity to M225) human FR sequence that incorporates at the 17 FR consensus positions the permutations of the naturally observed amino acid diversities. Ten clones were selected from the combinatorial library expressing phage-displayed humanized M225 Fabs. Surprisingly, 2 of the 10 clones were found to bind EGFR with stronger affinity than M225. Cell-based assays demonstrated that the 10 selected clones retained epitope specificity by blocking EGFR phosphorylation and thus hindering cellular proliferation. Our results suggest that there is a universal and structurally rigid near-CDR set of FR positions that cooperatively support the binding conformation of CDRs.  相似文献   

18.
Bioinformatics has emerged as an integral part of life sciences and biomedical research. The bioinformatics tools developed so far exist individually and do not cross talk leading biologists to spend more time in formatting the output from one tool as input for another tool. This leads to huge loss of time and cost. We herein have made platform which integrates the tools in a way that the output of one program can be directly used as input of another and does not need any modifications. Tools for similarity search, primer designing, and restriction enzyme digestion are required in almost all biological research; therefore we initially tried to integrate these tools. BioParisodhana platform optimizes the time spend in browsing and downloading applications and is an interactive, effective and user friendly. AVAILABILITY: The database is available for free at http://resource.ibab.ac.in/bioparishodhana.html.  相似文献   

19.
An interactive computer program for the rapid computation of Most Probable Numbers (MPN) with 95% confidence intervals and goodness-of-fit, is presented. The program, written in ‘MICROSOFT BASIC’ employs an iterative algorithm based on a modification of the Newton-Raphson method and accomodates any number of replicates up to ten dilutions. It is applicable to most microcomputers with little or no modification. Since the computed MPN, confidence interval,a nd goodness-of-fit tests are displayed simultaneously, MPN tables are no longer required.  相似文献   

20.
<正>It is our great honor to guest-edit this Thematic Issue on Bioinformatics in Science China Life Sciences.In recent years,a strong cohort of Chinese scientists has emerged as leading scholars in the exciting fields of bioinformatics and computational biology.In this issue,we are pleased to present outstanding research work produced from 10 world renowned researchers.System biology and metagenomics are recently revitalized by the inception of next-generation sequencing technologies.The former seeks to understand the function and  相似文献   

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