7CBK:
reference: Structural Basis for the Inhibition Mechanism of Ecotin against Neutrophil Elastase by Targeting the Active Site and Secondary Binding Site., Jobichen C, Prabhakar MT, Loh SN, Sivaraman J, Biochemistry. 2020 Aug 4;59(30):2788-2795. doi: 10.1021/acs.biochem.0c00493. Epub, 2020 Jul 21. PMID: 32657577

This OCA Structure page
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