BIOINORGANIC CHEMISTRY A Short Course Second Edition

α 2 α 1

β 2 β 1

H+

e-

e- e-

e-

heme f

heme bp

heme bn

chlorophyll a

heme x

TDS

Cytochrome b(6)f

PDB: 1VF5

Electron transfer

Proton transport

lumen (p) side

stromal (n) side

e-

to plastocyanin or cytochrome c 6

28.7 Å

29.1 Å

20.4 Å

β-carotene

TDS = tridecylstigmatellin

PQ = plastoquinone

PQH 2 = plastoquinol

PQH 2

2H+

PQ

2Fe-2S

Figure 7.2 Quaternary structure of deoxyhemoglobin tetramer (PDB: 4HHB). Visual-
ized using The PyMOL Molecular Graphics System and ChemDraw Ultra, version 10.0.
(Printed with permission of Delano Scientifi c, LLC and CambridgeSoft Corporation.)

Figure 7.26 Electron transfer and proton transport in cytochrome b(6)f: cofactors
(PDB: 1VF5). Visualized using The PyMOL Molecular Graphics System and
ChemDraw Ultra, version 10.0. (Printed with permission of Delano Scientifi c, LLC
and CambridgeSoft Corporation.)