Elucidation of the axial coordination mode in Stellacyanin

FERNÁNDEZ, C.O.; SANNAZZARO, A.I.; VILA, A.J.

Buenos Aires, Argentina

Congreso; III Congreso Iberoamericano de Biofísica; 1997

Sociedad Argentina de Biofísica

Stellacyanin from Rhus vernificera is a blue copper protein in which the metal is coordinated to a Cys, two His and a Gin residue. We have studied the Ni(II) derivative of stellacyanin by paramagnetic ~H NMR spectroscopy. The NMR spectrum resembles that ofNi(I1) Met l21Glnazurin, indicating a similar coordination environment. The hyperfine signals were assigned by means of I D and 2D NOE spectroscopy. Evidence is obtained which indicates that the Gln residue is bound to the metal through its oxigen atom