The coordination geometries around the copper ion of plastocyanin (a blue-copper protein) in oxidized and reduced form, respectively are
(a)tetrahedral and square-planar
(b)square-planar and tetrahedral
(c)distorted tetrahedral for both
(d)ideal tetrahedral for both
Answer
Answer: C ✓ checked by 4AB · confidence high
The source book printed no answer; this one was worked out and checked — see the explanation.
Printed D; the blue-copper site is distorted, not ideal, in both oxidation states.
Explanation
In plastocyanin the copper sits in a distorted tetrahedral (2 His, Cys, Met) site in both Cu(II) and Cu(I) forms — the entatic state that makes the electron transfer fast. The printed D (ideal tetrahedral) is wrong.