1IAE:
reference: Crystal structures, spectroscopic features, and catalytic properties of cobalt(II), copper(II), nickel(II), and mercury(II) derivatives of the zinc endopeptidase astacin. A correlation of structure and proteolytic activity., Gomis-Ruth FX, Grams F, Yiallouros I, Nar H, Kusthardt U, Zwilling R, Bode W, Stocker W, J Biol Chem 1994 Jun 24;269(25):17111-7. PMID: 8006015

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