SABIO-RK: Curated Kinetic Data of Biochemical Reactions

SABIO-RK ("http://sabio.villa-bosch.de/SABIORK/":http://sabio.villa-bosch.de/SABIORK/) is a curated, web-accessible database for modellers and wet-lab scientists to get comprehensive information about biochemical reactions and their kinetic properties. It integrates data from different origin in order to facilitate the access to reaction kinetics data and corresponding information. Since most of the kinetic data is exclusively found in the literature SABIO-RK offers data manually extracted from the literature and related information obtained from other publicly available biological databases. For instance, the kinetic data are related to reactions, organisms, tissues and cellular locations. The type of the kinetic mechanism and corresponding rate equations are presented together with their parameters and experimental conditions. Additionally, SABIO-RK also includes data about the detailed mechanism for some of the reactions based on literature information. This not only includes the graphical representation of the mechanism but also the single reaction steps with their corresponding kinetic data.

The data in SABIO-RK are extracted manually from literature and the selection of articles is not restricted to any biological source (e.g. organisms or organism classifications). All the data are curated and annotated by biological experts using a web-based input interface. To support the curation process and data integration we have implemented different constraints in the input interface and offer several controlled vocabularies as lists of values, as well as additional semi-automatic consistency checks to avoid errors and inconsistencies in the database. Controlled vocabularies and annotations to external resources and ontologies were used to identify and relate the data to their biological context. All these efforts to unify and integrate the data augment the content and the semantics of the SABIO-RK database entries to enable a comprehensive understanding and comparison of the data for the user.

SABIO-RK can be accessed via a web-based user interface or via web-services. The user interface allows the definition of complex queries by specifying reactions and reaction participants, kinetic parameters, environmental conditions or literature sources. Links to other databases based on the annotations of the
data enable the user to gather further information for example for compounds, reactions or proteins. Selected data about reactions and their kinetics, together with their annotations, can be exported in SBML (Systems Biology Mark-up Language), a widely used standard exchange format in systems biology

Exchanging Experimental Kinetic Data via SabioML

The simulation of quantitative biochemical models not only requires qualitative information about the stoichiometry of the described networks, but also kinetic data describing their dynamics. Such kinetic data have to be experimentally measured, collected, systematically structured and stored to finally make them accessible. However, the dataflow from the experiment to the model is still a bottleneck, calling for systems that capture the data directly from the instrument, process and normalize it to agreed standards and finally transfer the data to publicly available databases.

SABIO-RK (http://sabio.h-its.org) is a curated database system which we have developed for bundling data referring to biochemical reactions and their kinetics. It offers data for metabolic pathways and as a novelty also for signalling reactions. Until recently, the database solely has been compiled through manual data mining of published papers and merging the kinetic data excerpt with information collected from other databases. We have designed the novel XML-based schema SabioML for exchanging experimentally derived kinetic data and corresponding metadata between programs or databases. The schema is tailored to SABIO-RK, however also could serve for transferring data between other resources. It comprises the description of kinetic laws with their parameters and relevant metadata in a structured and standardised format applying controlled vocabulary, as well as the possibility to assign annotations complying with the MIRIAM standard (Minimum Information Required In the Annotation of Models). Based on this data description format we have developed a submission interface that allows transfer of reaction kinetics data directly from the experimental instrument to the SABIO-RK database. The data can be accessed by the submitting researcher and, after release by the submitter and curation to ensure completeness of the data, also by the public, either manually via a web-based user interface or automated via web-services, both supporting the export of the data together with its annotations in SBML (Systems Biology Mark-up Language).

The system introduced here considerably facilitates the exchange of kinetic data between experimentalists and modelers. We are convinced that in systems biology it will become quite useful for the integration of the results of high throughput assays into biochemical computer models for simulation.

References:

Swainston N, Golebiewski M, et al., FEBS Journal 277(18): 3769-3779 (September 2010)

Rojas I, Golebiewski M, et al., In Silico Biology 7(2 Suppl): S37-44 (2007)
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Path2Models: large-scale generation of computational models from biochemical pathway maps

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