Showing papers by "David S. Wishart published in 2005"

Circular genome visualization and exploration using CGView

Abstract: Summary: CGView (Circular Genome Viewer) is a Java application and library for generating high-quality, zoomable maps of circular genomes. It converts XML or tab-delimited input into a graphical map (PNG, JPG or Scalable Vector Graphics format), complete with sequence features, labels, legends and footnotes. In addition to the default full view map, the program can generate a series of hyperlinked maps showing expanded views. The linked maps can be explored using any Web browser, allowing rapid genome browsing and facilitating data sharing. Availability: CGView (the standalone application, library or applet), sample input, sample maps and documentation can be obtained from http://wishart.biology.ualberta.ca/cgview/ Contact: david.wishart@ualberta.ca

A Simple Method To Predict Protein Flexibility Using Secondary Chemical Shifts

Abstract: Protein motions play a critical role in many biological processes, such as enzyme catalysis, allosteric regulation, antigen−antibody interactions, and protein−DNA binding. NMR spectroscopy occupies a unique place among methods for investigating protein dynamics due to its ability to provide site-specific information about protein motions over a large range of time scales. However, most NMR methods require a detailed knowledge of the 3D structure and/or the collection of additional experimental data (NOEs, T1, T2, etc.) to accurately measure protein dynamics. Here we present a simple method based on chemical shift data that allows accurate, quantitative, site-specific mapping of protein backbone mobility without the need of a three-dimensional structure or the collection and analysis of NMR relaxation data. Further, we show that this chemical shift method is able to quantitatively predict per-residue RMSD values (from both MD simulations and NMR structural ensembles) as well as model-free backbone order pa...

BASys: a web server for automated bacterial genome annotation.

Abstract: BASys (Bacterial Annotation System) is a web server that supports automated, in-depth annotation of bacterial genomic (chromosomal and plasmid) sequences. It accepts raw DNA sequence data and an optional list of gene identification information and provides extensive textual annotation and hyperlinked image output. BASys uses .30 programs to determine 60 annotation subfields for each gene, including gene/protein name, GO function, COG function, possible paralogues and orthologues, molecular weight, isoelectric point, operon structure, subcellular localization, signal peptides, transmembrane regions, secondary structure, 3D structure, reactions and pathways. The depth and detail of a BASys annotation matches or exceeds that found in a standard SwissProt entry. BASys also generates colorful, clickable and fully zoomable maps of each query chromosome to permit rapid navigation and detailed visual analysis of all resulting gene annotations. The textual annotations and images that are provided by BASys can be generated in 24 h for an average bacterial chromosome (5 Mb). BASys annotations may be viewed and downloaded anonymously or through a password protected access system. The BASys server and databases can also be downloaded and run locally. BASys is accessible at http://wishart.biology. ualberta.ca/basys.

Identification of Novel and Known Oocyte-Specific Genes Using Complementary DNA Subtraction and Microarray Analysis in Three Different Species

Abstract: The main objective of the present study was to identify novel oocyte-specific genes in three different species: bovine, mouse, and Xenopus laevis. To achieve this goal, two powerful technologies were combined: a polymerase chain reaction (PCR)-based cDNA subtraction, and cDNA microarrays. Three subtractive libraries consisting of 3456 clones were established and enriched for oocyte-specific transcripts. Sequencing analysis of the positive insert-containing clones resulted in the following classification: 53% of the clones corresponded to known cDNAs, 26% were classified as uncharacterized cDNAs, and a final 9% were classified as novel sequences. All these clones were used for cDNA microarray preparation. Results from these microarray analyses revealed that in addition to already known oocyte-specific genes, such as GDF9, BMP15, and ZP, known genes with unknown function in the oocyte were identified, such as a MLF1-interacting protein (MLF1IP), B-cell translocation gene 4 (BTG4), and phosphotyrosine-binding protein (xPTB). Furthermore, 15 novel oocyte-specific genes were validated by reverse transcription-PCR to confirm their preferential expression in the oocyte compared to somatic tissues. The results obtained in the present study confirmed that microarray analysis is a robust technique to identify true positives from the suppressive subtractive hybridization experiment. Furthermore, obtaining oocyte-specific genes from three species simultaneously allowed us to look at important genes that are conserved across species. Further characterization of these novel oocyte-specific genes will lead to a better understanding of the molecular mechanisms related to the unique functions found in the oocyte.

Dynamic cellular automata: an alternative approach to cellular simulation.

Abstract: A wide variety of approaches, ranging from Petri nets to systems of partial differential equations, have been used to model very specific aspects of cellular or biochemical functions. Here we describe how an agent-based or dynamic cellular automata (DCA) approach can be used as a very simple, yet very general method to model many different kinds of cellular or biochemical processes. Specifically, using simple pairwise interaction rules coupled with random object moves to simulate Brownian motion, we show how the DCA approach can be used to easily and accurately model diffusion, viscous drag, enzyme rate processes, metabolism (the Kreb's cycle), and complex genetic circuits (the repressilator). We also demonstrate how DCA approaches are able to accurately capture the stochasticity of many biological processes. The success and simplicity of this technique suggests that many other physical properties and significantly more complicated aspects of cellular behavior could be modeled using DCA methods. An easy-to-use, graphically-based computer program, called SimCell, was developed to perform the DCA simulations described here. It is available at http://wishart.biology.ualberta.ca/SimCell/.

NMR Spectroscopy and Protein Structure Determination: Applications to Drug Discovery and Development

Abstract: Recent technological advances in NMR methods and instrumentation are having a significant impact in structural biology. These innovations are also impacting pharmaceutical biotechnology as it is now possible to use NMR spectroscopy to rapidly characterize a growing number of prospective protein drugs and protein drug targets. This review provides a general summary of how solution-state NMR can be used to determine protein structures. It also focuses on exploring how advances in solution state NMR are changing the way in which protein structures can be determined and protein-ligand interactions can be characterized. Recent innovations in protein sample preparation, in instrumentation and data collection, in spectral assignment and in structure generation are highlighted. The impact of solution-state NMR on pharmaceutical biotechnology is also discussed, with a special emphasis on describing how NMR has been used to study a number of pharmaceutically important proteins and how NMR is currently being used to rapidly screen and to map the binding sites of small molecules to a range of protein targets.

MovieMaker: a web server for rapid rendering of protein motions and interactions

Abstract: MovieMaker is a web server that allows short (10 s), downloadable movies of protein motions to be generated. It accepts PDB files or PDB accession numbers as input and automatically calculates, renders and merges the necessary image files to create colourful animations covering a wide range of protein motions and other dynamic processes. Users have the option of animating (i) simple rotation, (ii) morphing between two end-state conformers, (iii) shortscale, picosecond vibrations, (iv) ligand docking, (v) protein oligomerization, (vi) mid-scale nanosecond (ensemble) motions and (vii) protein folding/ unfolding. MovieMaker does not perform molecular dynamics calculations. Instead it is an animation tool that uses a sophisticated superpositioning algorithm in conjunction with Cartesian coordinate interpolation to rapidly and automatically calculate the intermediate structures needed for many of its animations. Users have extensive control over the rendering style, structure colour, animation quality, background and other image features. MovieMaker is intended to be a general-purpose server that allows both experts and non-experts to easily generate useful, informative protein animations for educational and illustrative purposes. MovieMaker is accessible at http://wishart.biology.ualberta.ca/moviemaker.

Bioinformatics in Drug Development and Assessment

Abstract: Bioinformatics is playing an increasingly important role in nearly all aspects of drug discovery, drug assessment, and drug development. This growing importance lies not only in the role that bioinformatics plays in handling large volumes of data, but also in the utility of bioinformatics tools to predict, analyze, or help interpret clinical and preclinical findings. This review focuses on describing and evaluating some of the newer or more important bioinformatics resources (i.e., databases and software) that are of growing importance to understanding or predicting drug metabolism, especially with respect to the absorption, distribution, metabolism, excretion, (ADME), and toxicity (T) of both existing drugs and potential drug leads. Detailed descriptions and critical assessments of a number of potentially useful bioinformatics/cheminformatics databases and predictive ADMET software tools are provided. Additionally, several pharmaceutically important applications of both the databases and software are highlighted. Given the rapid growth in this area and the rapid changes that are taking place, a special emphasis is placed on freely available or Web-accessible resources.

A simple method to adjust inconsistently referenced 13C and 15N chemical shift assignments of proteins

Abstract: Inconsistent 13C and 15N chemical shift referencing is a continuing problem associated with protein chemical shift assignments deposited in BioMagResBank (BMRB). Here we describe a simple and robust approach that can quantitatively determine the 13C and 15N referencing offsets solely from chemical shift assignment data and independently of 3D coordinate data. This novel structure-independent approach permitted the assessment and determination of 13C and 15N reference offsets for all protein entries deposited in the BMRB. Tests on 452 proteins with known 3D structures show that this structure-independent approach yields 13C and 15N referencing offsets that exhibit excellent agreement with those calculated on the basis of 3D structures. Furthermore, this protocol appears to improve the accuracy of chemical shift-derived secondary structural identification, and has been formally incorporated into a computer program called PSSI (http//www.pronmr.com).

Pathway Analyst Automated Metabolic Pathway Prediction

Abstract: Metabolic pathways are crucial to our understanding of biology. The speed at which new organisms are being sequenced is outstripping our ability to experimentally determine their metabolic pathway information. In recent years several initiatives have been successful in automating the annotations of individual proteins in these organisms, either experimentally or by prediction. However, to leverage the success of metabolic pathways we need to automate their identification in our rapidly growing list of sequenced organisms. We present a prototype system for predicting the catalysts of important reactions and for organizing the predicted catalysts and reactions into previously defined metabolic pathways. We compare a variety of predictors that incorporate sequence similarity (BLAST), hidden Markov models (HMM) and Support Vector Machines (SVM). We found that there is an advantage to using different predictors for different reactions. We validate our prototype on 10 metabolic pathways across 13 organisms for which we obtained a cross-validation precision of 71.5% and recall of 91.5% in predicting the catalyst proteins of all reactions.

Solution Structure of MTH0776 from Methanobacterium Thermoautotrophicum

Abstract: Godwin Amegbey, Paul Stothard, Ekaterina Kuznetsova, Adelinda Yee, Cheryl H. Arrowsmith & David S. Wishart* Departments of Computing Science and Biological Sciences, University of Alberta, Edmonton, Alberta, Canada T6G 2E8; Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada M5G 1L6; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada M5G 2C4

Contract, oppression and agreements with indigenous peoples.

Abstract: Australian Native Title Act 1993 provides for the making and registration of agreements with regard to native title and other matters. Native title claims in the Federal Court can be settled by agreement, and there are a variety of forms of agreement quite outside the Native Title Act.

The proteome analyst suite of automated function prediction tools

Abstract: Proteome Analyst (PA) is a publicly available, high-throughput, web-based system for automatically predicting the function and properties of proteins. Biologists can use PA to predict, for example, the Gene Ontology (GO) molecular function and subcellular localization of a protein based on sequence information. Using sequence analysis tools and machine learning, PA gives high accuracy and broad coverage for both molecular function and subcellular localization predictions.