4R9I:
reference: Structural insights into the unique inhibitory mechanism of the silkworm protease inhibitor serpin18., Guo PC, Dong Z, Zhao P, Zhang Y, He H, Tan X, Zhang W, Xia Q, Sci Rep. 2015 Jul 7;5:11863. doi: 10.1038/srep11863. PMID: 26148664

This OCA Structure page
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