Positions of Q(A)and Chl(Z)Relative to Tyrosine Y(Z)and Y(D)in Photosystem II Studied by Pulsed EPR.
PELDOR (Pulsed Electron eLectron DOuble Resonance) was applied to determinethe distance of between Y(Z)and Q(A) (-)inY(D)-less mutant of Chlamydomonas reinhardtiiin Tris-treatedand Zn-substituted preparation of photosystem II. The value of distance wasfound to be 34.5 ± 1 Â. A '2+1' electron spin echo method has beenapplied to measure the orientation of the radius-vector RfomY(D)to Chl(Z)in a membrane-oriented photosystem II. The anglebetween Rand the membrane normal nwas determined to be 50 ±5(°), using the distance 29.4 ± 0.5 Â determined in non-orientedPS II.
Faculty of Science, Kwansei Gakuin University, Gakuen 2-1, Sanda, 669-1337 Japan.
A
A
Kawamori
N
N
Katsuta
H
H
Mino
A
A
Ishii
J
J
Minagawa
T-A
TA
Ono
Chlamydomonas reinhardtii; Chlorophyll Z; PS II; QA; YD; YD-less mutant; YZ; positions; pulsed EPR