title: Evidence for deep acceptor centers in plant photosystem I crystals.
abstract: Dry micrometer-thick crystalline photosystem I (PSI) has been shown to generate unprecedented large photovoltage under illumination. We use variable-temperature Kelvin probe force microscopy to show that deep acceptor centers are responsible for this anomalous photovoltage. We assumed that these centers are located close to the positively charged F(B)(2+) clusters, forming a coupled center that effectively captures the photoexcited electron into a deep state. We extract the main inherent parameters of the deep centers, which are extremely important in the potential use of photosynthetic proteins in various optoelectronic devices.
authors.affiliation: Department of Physical Electronics, Faculty of Engineering, and ‡Department of Biochemistry and Molecular Biology, Faculty of Life Sciences, Tel Aviv University , Tel Aviv 69978, Israel.
authors.forename: Irina
authors.initials: I
authors.lastname: Volotsenko
authors.forename: Michel
authors.initials: M
authors.lastname: Molotskii
authors.forename: Anna
authors.initials: A
authors.lastname: Borovikova
authors.forename: Nathan
authors.initials: N
authors.lastname: Nelson
authors.forename: Yossi
authors.initials: Y
authors.lastname: Rosenwaks
mesh_terms: D003460:Crystallization; D045331:Photosystem I Protein Complex / Q000737:chemistry*; D010940:Plant Proteins / Q000737:chemistry*; D013696:Temperature
chemical_list: D045331:Photosystem I Protein Complex; D010940:Plant Proteins