1K9B:
reference: Crystal structure of the bifunctional soybean Bowman-Birk inhibitor at 0.28-nm resolution. Structural peculiarities in a folded protein conformation., Voss RH, Ermler U, Essen LO, Wenzl G, Kim YM, Flecker P, Eur J Biochem 1996 Nov 15;242(1):122-31. PMID: 8954162

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