The PSI semantic validator: A framework to check MIAPE compliance of proteomics data

The Human Proteome Organization's Proteomics Standards Initiative (PSI) promotes the development of exchange standards to improve data integration and interoperability. PSI specifies the suitable level of detail required when reporting a proteomics experiment (via the Minimum Information About a Proteomics Experiment), and provides extensible markup language (XML) exchange formats and dedicated controlled vocabularies (CVs) that must be combined to generate a standard compliant document. The framework presented here tackles the issue of checking that experimental data reported using a specific format, CVs and public bio‐ontologies (e.g. Gene Ontology, NCBI taxonomy) are compliant with the Minimum Information About a Proteomics Experiment recommendations. The semantic validator not only checks the XML syntax but it also enforces rules regarding the use of an ontology class or CV terms by checking that the terms exist in the resource and that they are used in the correct location of a document. Moreover, this framework is extremely fast, even on sizable data files, and flexible, as it can be adapted to any standard by customizing the parameters it requires: an XML Schema Definition, one or more CVs or ontologies, and a mapping file describing in a formal way how the semantic resources and the format are interrelated. As such, the validator provides a general solution to the common problem in data exchange: how to validate the correct usage of a data standard beyond simple XML Schema Definition validation. The framework source code and its various applications can be found at http://psidev.info/validator .     

Storing biological sequence databases in relational form

SUMMARY: We have created a set of applications using Perl and Java in combination with XML technology to install biological sequence databases into an Oracle RDBMS. An easy-to-use interface using Java has been created for database query and other tools developed to integrate with our in-house bioinformatics applications. AVAILIBILITY: The database schema, DTD file, and source codes are available from the authors via email. CONTACT: guochun_ xie@merck. com     

Simultaneous modelling of metabolic, genetic and product-interaction networks

The creation of cell models from annotated genome information, as well as additional data from other databases, requires both a format and medium for its distribution. Standards are described for the representation of the data in the form of Document Type Definitions (DTDs) for XML files. Separate DTDs are detailed for genetic, metabolic and gene product-interaction networks, which can be used to hold information on individual subsystems, or which may be combined to create a whole cell DTD. In the execution of this work, a fifth DTD was also created for a metabolite thesaurus, which allows incorporation of metabolite synonyms and generic nomenclature data into the models. A gene-regulation classification scheme was also created, to facilitate incorporation of gene regulatory information in an efficient manner. The work is described with particular reference to the metabolic network of Escherichia coli, which contains 808 individual enzymes. The assignment of confidence levels to these data, through the use of Gene Ontology evidence codes, is highlighted. In silico investigations may now be performed using the mathematical simulation workbench, DBsolve, which incorporates the facility to introduce data directly from XML.     

XML, bioinformatics and data integration

Motivation: The eXtensible Markup Language (XML) is an emerging standard for structuring documents, notably for the World Wide Web. In this paper, the authors present XML and examine its use as a data language for bioinformatics. In particular, XML is compared to other languages, and some of the potential uses of XML in bioinformatics applications are presented. The authors propose to adopt XML for data interchange between databases and other sources of data. Finally the discussion is illustrated by a test case of a pedigree data model in XML. Contact: Emmanuel.Barillot@infobiogen.fr     

Bioinformatics data distribution and integration via Web Services and XML

It is widely recognized that exchange, distribution, and integration of biological data are the keys to improve bioinformatics and genome biology in post-genomic era. However, the problem of exchanging and integrating biological data is not solved satisfactorily. The extensible Markup Language (XML) is rapidly spreading     

Pedro: a configurable data entry tool for XML

Pedro is a Java application that dynamically generates data entry forms for data models expressed in XML Schema, producing XML data files that validate against this schema. The software uses an intuitive tree-based navigation system, can supply context-sensitive help to users and features a sophisticated interface for populating data fields with terms from controlled vocabularies. The software also has the ability to import records from tab delimited text files and features various validation routines. AVAILABILITY: The application, source code, example models from several domains and tutorials can be downloaded from http://pedro.man.ac.uk/.     

A common registration-to-publication automated pipeline for nomenclatural acts for higher plants (International Plant Names Index,IPNI), fungi (Index Fungorum,MycoBank) and animals (ZooBank)

Collaborative effort among four lead indexes of taxon names and nomenclatural acts ( International Plant Name Index (IPNI), Index Fungorum, MycoBank and ZooBank) and the journals PhytoKeys, MycoKeys and ZooKeys to create an automated, pre-publication, registration workflow, based on a server-to-server, XML request/response model. The registration model for ZooBank uses the TaxPub schema, which is an extension to the Journal Tag Publishing Suite (JATS) of the National Library of Medicine (NLM). The indexing or registration model of IPNI and Index Fungorum will use the Taxonomic Concept Transfer Schema (TCS) as a basic standard for the workflow. Other journals and publishers who intend to implement automated, pre-publication, registration of taxon names and nomenclatural acts can also use the open sample XML formats and links to schemas and relevant information published in the paper.     

StarDOM: From STAR format to XML

StarDOM is a software package for the representation of STAR files as document object models and the conversion of STAR files into XML. This allows interactive navigation by using the Document Object Model representation of the data as well as easy access by XML query languages. As an example application, the entire BioMagResBank has been transformed into XML format. Using an XML query language, statistical queries on the collected NMR data sets can be constructed with very little effort. The BioMagResBank/XML data and the software can be obtained at http://www.nmr.embl-heidelberg.de/nmr/StarDOM/     

VitaPad: visualization tools for the analysis of pathway data

MOTIVATION: Packages that support the creation of pathway diagrams are limited by their inability to be readily extended to new classes of pathway-related data. RESULTS: VitaPad is a cross-platform application that enables users to create and modify biological pathway diagrams and incorporate microarray data with them. It improves on existing software in the following areas: (i) It can create diagrams dynamically through graph layout algorithms. (ii) It is open-source and uses an open XML format to store data, allowing for easy extension or integration with other tools. (iii) It features a cutting-edge user interface with intuitive controls, high-resolution graphics and fully customizable appearance. AVAILABILITY: http://bioinformatics.med.yale.edu CONTACTS: matthew.holford@yale.edu; hongyu.zhao@yale.edu.     

The Binding Database: data management and interface design

MOTIVATION: The large and growing body of experimental data on biomolecular binding is of enormous value in developing a deeper understanding of molecular biology, in developing new therapeutics, and in various molecular design applications. However, most of these data are found only in the published literature and are therefore difficult to access and use. No existing public database has focused on measured binding affinities and has provided query capabilities that include chemical structure and sequence homology searches. METHODS & RESULTS: We have created Binding DataBase (BindingDB), a public, web-accessible database of measured binding affinities. BindingDB is based upon a relational data specification for describing binding measurements via Isothermal Titration Calorimetry (ITC) and enzyme inhibition. A corresponding XML Document Type Definition (DTD) is used to create and parse intermediate files during the on-line deposition process and will also be used for data interchange, including collection of data from other sources. The on-line query interface, which is constructed with Java Servlet technology, supports standard SQL queries as well as searches for molecules by chemical structure and sequence homology. The on-line deposition interface uses Java Server Pages and JavaBean objects to generate dynamic HTML and to store intermediate results. The resulting data resource provides a range of functionality with brisk response-times, and lends itself well to continued development and enhancement.     

NeXML: rich, extensible, and verifiable representation of comparative data and metadata

In scientific research, integration and synthesis require a common understanding of where data come from, how much they can be trusted, and what they may be used for. To make such an understanding computer-accessible requires standards for exchanging richly annotated data. The challenges of conveying reusable data are particularly acute in regard to evolutionary comparative analysis, which comprises an ever-expanding list of data types, methods, research aims, and subdisciplines. To facilitate interoperability in evolutionary comparative analysis, we present NeXML, an XML standard (inspired by the current standard, NEXUS) that supports exchange of richly annotated comparative data. NeXML defines syntax for operational taxonomic units, character-state matrices, and phylogenetic trees and networks. Documents can be validated unambiguously. Importantly, any data element can be annotated, to an arbitrary degree of richness, using a system that is both flexible and rigorous. We describe how the use of NeXML by the TreeBASE and Phenoscape projects satisfies user needs that cannot be satisfied with other available file formats. By relying on XML Schema Definition, the design of NeXML facilitates the development and deployment of software for processing, transforming, and querying documents. The adoption of NeXML for practical use is facilitated by the availability of (1) an online manual with code samples and a reference to all defined elements and attributes, (2) programming toolkits in most of the languages used commonly in evolutionary informatics, and (3) input-output support in several widely used software applications. An active, open, community-based development process enables future revision and expansion of NeXML.     

A Comparison of Database Systems for XML-Type Data

Background: In the field of bioinformatics interchangeable data formats based on XML are widely used. XML-type data is also at the core of most web services. With the increasing amount of data stored in XML comes the need for storing and accessing the data. In this paper we analyse the suitability of different database systems for storing and querying large datasets in general and Medline in particular.Results: All reviewed database systems perform well when tested with small to medium sized datasets, however when the full Medline dataset is queried a large variation in query times is observed. Conclusions: There is not one system that is vastly superior to the others in this comparison and, depending on the database size and the query requirements, different systems are most suitable. The best all-round solution is the Oracle 11~g database system using the new binary storage option. Alias-i's Lingpipe is a more lightweight, customizable and sufficiently fast solution. It does however require more initial configuration steps. For data with a changing XML structure Sedna and BaseX as native XML database systems or MySQL with an XML-type column are suitable.     

A flexible online metadata editing and management system

Our team developed a metadata editing and management system employing state of the art XML technologies initially aimed at the environmental sciences but with the potential to be useful across multiple domains. We chose a modular and distributed design for scalability, flexibility, options for customizations, and the possibility to add more functionality at a later stage. The system consists of a desktop design tool that generates code for the actual online editor, a native XML database, and an online user access management application. A Java Swing application that reads an XML schema, the design tool provides the designer with options to combine input fields into online forms with user-friendly tags and determine the flow of input forms. Based on design decisions, the tool generates XForm code for the online metadata editor which is based on the Orbeon XForms engine. The design tool fulfills two requirements: First data entry forms based on a schema are customized at design time and second the tool can generate data entry applications for any valid XML schema without relying on custom information in the schema. A configuration file in the design tool saves custom information generated at design time. Future developments will add functionality to the design tool to integrate help text, tool tips, project specific keyword lists, and thesaurus services.Cascading style sheets customize the look-and-feel of the finished editor. The editor produces XML files in compliance with the original schema, however, a user may save the input into a native XML database at any time independent of validity. The system uses the open source XML database eXist for storage and uses a MySQL relational database and a simple Java Server Faces user interface for file and access management. We chose three levels to distribute administrative responsibilities and handle the common situation of an information manager entering the bulk of the metadata but leave specifics to the actual data provider.     

XML schemas and mark-up practices of taxonomic literature

We review the three most widely used XML schemas used to mark-up taxonomic texts, TaxonX, TaxPub and taXMLit. These are described from the viewpoint of their development history, current status, implementation, and use cases. The concept of "taxon treatment" from the viewpoint of taxonomy mark-up into XML is discussed. TaxonX and taXMLit are primarily designed for legacy literature, the former being more lightweight and with a focus on recovery of taxon treatments, the latter providing a much more detailed set of tags to facilitate data extraction and analysis. TaxPub is an extension of the National Library of Medicine Document Type Definition (NLM DTD) for taxonomy focussed on layout and recovery and, as such, is best suited for mark-up of new publications and their archiving in PubMedCentral. All three schemas have their advantages and shortcomings and can be used for different purposes.     

Further steps in standardisation. Report of the second annual Proteomics Standards Initiative Spring Workshop (Siena, Italy 17-20th April 2005)

The spring workshop of the HUPO-PSI convened in Siena to further progress the data standards which are already making an impact on data exchange and deposition in the field of proteomics. Separate work groups pushed forward existing XML standards for the exchange of Molecular Interaction data (PSI-MI, MIF) and Mass Spectrometry data (PSI-MS, mzData) whilst significant progress was made on PSI-MS' mzIdent, which will allow the capture of data from analytical tools such as peak list search engines. A new focus for PSI (GPS, gel electrophoresis) was explored; as was the need for a common representation of protein modifications by all workers in the field of proteomics and beyond. All these efforts are contextualised by the work of the General Proteomics Standards workgroup; which in addition to the MIAPE reporting guidelines, is continually evolving an object model (PSI-OM) from which will be derived the general standard XML format for exchanging data between researchers, and for submission to repositories or journals.