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BRENDA Tissue Ontology

The BTO(BRENDA Tissue Ontology) represents a comprehensive structured encyclopedia. It provides terms, classifications, and definitions of tissues, organs, anatomical structures, plant parts, cell cultures, cell types, and cell lines of organisms from all taxonomic groups (animals, plants, fungis, protozoon) as enzyme sources. The information is connected to the functional data in the BRENDA (BRaunschweig ENzyme Database) enzyme information system.

Development of BTO started in 2003, aimed to connect the biochemical and molecular biological enzyme data of BRENDA with a hierarchical and standardized collection of tissue-specific terms. The functional enzyme data and information in BRENDA have been manually annotated and structured by experts from biochemistry, biology, and chemistry. By October 2019, the BTO contained over 6,042 terms, linked to 5,173 synonyms and 5,074 definitions. The terms are classified under generic categories, rules, and formats of the Gene Ontology Consortium (GO), organized as a directed acyclic graph (DAG) created using the open-source OBO-Edit. All terms from each level are directly connected to the enzyme data in BRENDA. BTO is a suitable tool to distinguish between different enzymes which are expressed in a tissue-specific manner.


cited as: The BRENDA Tissue Ontology (BTO): the first all-integrating ontology of all organisms for enzyme sources. Gremse M., Chang A., Schomburg I., Grote A., Scheer M., Ebeling C., Schomburg D., Nucleic Acids Res., 39:D507-13 (2011)


BTO is available under CC-BY 4.0

CC-BY 4.0