3VGC:
reference: Differences in binding modes of enantiomers of 1-acetamido boronic acid based protease inhibitors: crystal structures of gamma-chymotrypsin and subtilisin Carlsberg complexes., Stoll VS, Eger BT, Hynes RC, Martichonok V, Jones JB, Pai EF, Biochemistry 1998 Jan 13;37(2):451-62. PMID: 9425066

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