Structure of Photosystems I and II.
Photosynthesis is the major process that converts solar energy into chemical energy on Earth. Two and a half billion years ago, the ancestors of cyanobacteria were able to use water as electron source for the photosynthetic process, thereby evolving oxygen and changing the atmosphere of our planet Earth. Two large membrane protein complexes, Photosystems I and II, catalyze the primary step in this energy conversion, the light-induced charge separation across the photosynthetic membrane. This chapter describes and compares the structure of two Photosystems and discusses their function in respect to the mechanism of light harvesting, electron transfer and water splitting.
Fromme
Petra
P
Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287-1604, USA. pfromme@asu.edu
Grotjohann
Ingo
I
D002384:Catalysis; D000458:Cyanobacteria / Q000378:metabolism; D018534:Earth, Planet; D004579:Electron Transport; D008565:Membrane Proteins / Q000737:chemistry; D008954:Models, Biological; D008968:Molecular Conformation; D010100:Oxygen / Q000737:chemistry; D010788:Photosynthesis; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D010944:Plants / Q000378:metabolism; D017434:Protein Structure, Tertiary; D014867:Water / Q000737:chemistry; D014965:X-Rays
D008565:Membrane Proteins; D045331:Photosystem I Protein Complex; D045332:Photosystem II Protein Complex; D014867:Water; D010100:Oxygen