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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 ACTIVITYCRYSTAL 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
Structural highlights
FunctionASTA_ASTAS This protease prefers to cleave in front of small aliphatic residues (P1'). The presence of Lys or Arg in the P1 and P2 position yields high-turnover substrates. In the P3 position the enzyme prefers Pro > Val > Leu > Ala > Gly. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe catalytic zinc ion of astacin, a prototypical metalloproteinase from crayfish, has been substituted by Co(II), Cu(II), Hg(II), and Ni(II) in order to probe the role of the metal for both catalysis and structure. Compared to Zn(II)-astacin, Co(II)- and Cu(II)-astacin display enzymatic activities of about 140 and 37%, respectively, while Ni(II)- and Hg(II)-astacin are almost inactive. The electron paramagnetic resonance spectrum of Cu(II)-astacin is typical of 5-fold coordinated copper(II), and its intense absorption maxima at 445 and 325 nm are probably due to ligand-metal charge-transfer transitions involving Tyr-149. This residue had been identified previously by x-ray crystallography of the zinc enzyme as a zinc ligand, in addition to three imidazoles and a glutamic acid-bound water molecule. We present now the refined high-resolution x-ray crystal structures of Cu(II)-, Co(II)-, and Ni(II)-astacin, which exhibit a virtually identical protein framework to the previously analyzed structures of Zn(II)-, apo-, and Hg(II)-astacin. In Co(II)- and Cu(II)-astacin, the metal is penta-coordinated similarly to the native zinc enzyme. In the Ni(II) derivative, however, an additional solvent molecule expands the metal coordination sphere to a distorted octahedral ligand geometry, while in Hg(II)-astacin, no ordered solvent molecule at all is observed in the inner coordination sphere of the metal. This indicates a close correlation between catalytic properties and ground-state metal coordination of astacin. 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[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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