TY - JOUR
T1 - Light-induced charge separation across the photosynthetic membrane
T2 - a proposed structure for the photosystem I reaction center
AU - Golbeck, John H.
N1 - Funding Information:
This research was supported by a grant from the National Science Foundation (DMB-8517391) . The author thanks Dr . Donald Bryant for pointing out important features of the cyanobacterial reaction center and Dr . Joseph Warden for reviewing the manuscript prior to submission .
PY - 1987/9
Y1 - 1987/9
N2 - The photosystem I reaction center is reviewed from the standpoint of electron acceptors, polypeptide composition, and structural organization. Experimental difficulties in the current model are highlighted, and current results on the polypeptide location of each acceptor are reviewed. The amount of iron and labile sulfide, the types of iron-sulfur clusters, and the number of ∼ 64-kDa polypeptides are considered in light of a model for the reaction center. In particular, the presence of [2Fe-2S] clusters in photosystem I has significance in the structure and organization of Fx on the reaction center. Since four cysteinyl ligands are assumed to hold an iron-sulfur cluster, a photosystem I subunit may consist of two ∼ 64-kDa polypeptides bridged by a [2Fe-2S] cluster. The reaction center would consist of a symmetrical pair of these subunits positioned so that two [2Fe-2S] clusters are in magnetic interaction, thereby constituting Fx. The reaction center core would therefore incorporate four ∼ 64-kDa polypeptides and have a molecular weight in excess of 250 kDa.
AB - The photosystem I reaction center is reviewed from the standpoint of electron acceptors, polypeptide composition, and structural organization. Experimental difficulties in the current model are highlighted, and current results on the polypeptide location of each acceptor are reviewed. The amount of iron and labile sulfide, the types of iron-sulfur clusters, and the number of ∼ 64-kDa polypeptides are considered in light of a model for the reaction center. In particular, the presence of [2Fe-2S] clusters in photosystem I has significance in the structure and organization of Fx on the reaction center. Since four cysteinyl ligands are assumed to hold an iron-sulfur cluster, a photosystem I subunit may consist of two ∼ 64-kDa polypeptides bridged by a [2Fe-2S] cluster. The reaction center would consist of a symmetrical pair of these subunits positioned so that two [2Fe-2S] clusters are in magnetic interaction, thereby constituting Fx. The reaction center core would therefore incorporate four ∼ 64-kDa polypeptides and have a molecular weight in excess of 250 kDa.
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U2 - 10.1016/S0376-7388(00)80374-9
DO - 10.1016/S0376-7388(00)80374-9
M3 - Article
AN - SCOPUS:0022782331
VL - 33
SP - 151
EP - 168
JO - Journal of Membrane Science
JF - Journal of Membrane Science
SN - 0376-7388
IS - 2
ER -