Fig. 3.

A ¹H signal eliminating relaxation filter spectrum showing the hyperfine shifted signals in oxidized A.v. plastocyanin. The spectrum was recorded at 800 MHz by using the following parameters: R₁^o = 50 s⁻¹, R₁^S = 2s⁻¹, t_a (Δ₀) = 90 ms, ζ = 1, and τ = 91 ms. The assignment is (22): His-92 H^δ2 (A), His-39 H^δ2 (B), His-92 H^ε1 (C), His-39 H^ε1 (D), Met-97 H^γ2 (E), Asn-40 H^α (F), Met-97 H^γ1 (G), His-39 H^β1 (H), and Cys-89 H^α (I). The spectrum is in good agreement with those of other plastocyanins (22), indicating a close similarity of the metal site structures.