2TLD:
reference: Crystal structure of an engineered subtilisin inhibitor complexed with bovine trypsin., Takeuchi Y, Nonaka T, Nakamura KT, Kojima S, Miura K, Mitsui Y, Proc Natl Acad Sci U S A 1992 May 15;89(10):4407-11. PMID: 1584773

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