4TPI:
reference: The refined 2.2-A (0.22-nm) X-ray crystal structure of the ternary complex formed by bovine trypsinogen, valine-valine and the Arg15 analogue of bovine pancreatic trypsin inhibitor., Bode W, Walter J, Huber R, Wenzel HR, Tschesche H, Eur J Biochem 1984 Oct 1;144(1):185-90. PMID: 6207021

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