Where Water is Oxidized to Dioxygen: Structure of thePhotosynthetic Mn4Ca Cluster

Journal Article · Wed May 31 00:00:00 EDT 2006 · Science

DOI:https://doi.org/10.1126/science.1128186· OSTI ID:902445

Yano, Junko; Kern, Jan; Sauer, Kenneth; Latimer, Matthew J; Pushkar, Yulia; Biesiadka, Jacek; Loll, Bernhard; Saenger, Wolfram; Messinger, Johannes; Zouni, Athina; Yachandra, Vittal K

Oxidation of water to dioxygen is catalyzed withinphotosystem II (PSII) by a Mn4Ca cluster, the structure of which remainselusive. Polarized extended X-ray absorption fine structure (EXAFS)measurements on PSII single crystals constrain the Mn4Ca cluster geometryto a set of three similar high-resolution structures. Combining polarizedEXAFS and X-ray diffraction data, the cluster was placed within PSIItaking into account the overall trend of the electron density of themetal site and the putative ligands. The structure of the cluster fromthe present study is unlike either the 3.0 or 3.5 Angstrom resolutionX-ray structures, and other previously proposed models.

• Research Organization: Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE Director, Office of Science. Office of Basic EnergySciences; National Institutes of Health
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 902445
• Report Number(s): LBNL--60492; BnR: KC0304000
• Journal Information: Science, Journal Name: Science Journal Issue: 5800 Vol. 314; ISSN 0193-4511; ISSN SCEHDK
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
59 BASIC BIOLOGICAL SCIENCES
ABSORPTION
ELECTRON DENSITY
FINE STRUCTURE
GEOMETRY
MONOCRYSTALS
OXIDATION
RESOLUTION
WATER
X-RAY DIFFRACTION
water-oxidation oxygen-evolution photosynthesis Mncomplex