ChEMBL small molecule-protein interactions are now available in PSI-MI TAB and XML formats, thanks to the Proteomics Services group. This dataset includes ChEMBL interactions identified via binding assays with IC50/Ki/EC50/Kd values below 10uM - just under 500,000 interactions in total (with negative/weaker interactions also included in the XML export).
The data can be accessed via the PSICQUIC project (Proteomics Standards Initiative Common QUery InterfaCe), which provides programmatic access to a wide range of molecular interaction databases via SOAP and REST web services. For example, this URL retrieves all ChEMBL interactions relating to imatinib (Gleevec).
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