Probing the Metal Site in Rhus vernicifera Stellacyanin by Ni(II)-Substitution and Paramagnetic NMR Spectroscopy

FERNÁNDEZ C.O., SANNAZZARO A.I., DÍAZ L.E., AND VILA A.J.

INORGANICA CHIMICA ACTA

Elsevier

Año: 1998 vol. 273 p. 367 - 371

0020-1693

Stellacyanin from Rhus vernicifera is a blue copper protein in which the metal is coordinated to a Cys, two His and a Gln residue. We have studied the Ni(II) derivative of stellacyanin by paramagnetic 1H NMR spectroscopy. The NMR spectrum resembles that of Ni(II) Met121Gln azurin, indicating a similar coordination environment. The hyperfine signals were assigned by means of 1D and 2D NOE spectroscopy. Evidence is obtained which indicates that the Gln residue is bound to the metal through its oxygen atom.