Towards an artificial model for Photosystem II: a manganese(II,II) dimer covalently linked to ruthenium(II) tris-bipyridine via a tyrosine derivative
(2000) In Journal of Inorganic Biochemistry 78(1). p.15-22- Abstract
- In order to model the individual electron transfer steps from the manganese cluster to the photooxidized sensitizer P680+ in Photosystem II (PS II) in green plants, the supramolecular complex 4 has been synthesized. In this complex, a ruthenium(II) tris-bipyridine type photosensitizer has been linked to a manganese(II) dimer via a substituted l-tyrosine, which bridges the manganese ions. The trinuclear complex 4 was characterized by electron paramagnetic resonance (EPR) and electrospray ionization mass spectrometry (ESI-MS). The excited state lifetime of the the ruthenium tris-bipyridine moiety in 4 was found to be about 110 ns in acetonitrile. Using flash photolysis in the presence of an electron acceptor (methylviologen), it was... (More)
- In order to model the individual electron transfer steps from the manganese cluster to the photooxidized sensitizer P680+ in Photosystem II (PS II) in green plants, the supramolecular complex 4 has been synthesized. In this complex, a ruthenium(II) tris-bipyridine type photosensitizer has been linked to a manganese(II) dimer via a substituted l-tyrosine, which bridges the manganese ions. The trinuclear complex 4 was characterized by electron paramagnetic resonance (EPR) and electrospray ionization mass spectrometry (ESI-MS). The excited state lifetime of the the ruthenium tris-bipyridine moiety in 4 was found to be about 110 ns in acetonitrile. Using flash photolysis in the presence of an electron acceptor (methylviologen), it was demonstrated that in the supramolecular complex 4 an electron was transferred from the excited state of the ruthenium tris-bipyridine moiety to methylviologen, forming a methylviologen radical and a ruthenium(III) tris-bipyridine moiety. Next, the Ru(III) species retrieved the electron from the manganese(II/II) dimer in an intramolecular electron transfer reaction with a rate constant kET>1.0x107 s-1, generating a manganese(II/III) oxidation state and regenerating the ruthenium(II) photosensitizer. This is the first example of intramolecular electron transfer in a supramolecular complex, in which a manganese dimer is covalently linked to a photosensitizer via a tyrosine unit, in a process which mimics the electron transfer on the donor side of PS II. (Less)
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https://lup.lub.lu.se/record/125185
- author
- organization
- publishing date
- 2000
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Electron transfer, Artificial photosynthesis, Manganese dimer complexes, Ruthenium complexes, Photosystem II
- in
- Journal of Inorganic Biochemistry
- volume
- 78
- issue
- 1
- pages
- 15 - 22
- publisher
- Elsevier
- external identifiers
-
- scopus:0034651173
- ISSN
- 1873-3344
- DOI
- 10.1016/S0162-0134(99)00200-7
- language
- English
- LU publication?
- yes
- id
- 6faf34bc-bd61-4d48-b3b7-18bcad3167eb (old id 125185)
- date added to LUP
- 2016-04-01 16:28:57
- date last changed
- 2022-01-28 20:01:24
@article{6faf34bc-bd61-4d48-b3b7-18bcad3167eb, abstract = {{In order to model the individual electron transfer steps from the manganese cluster to the photooxidized sensitizer P680+ in Photosystem II (PS II) in green plants, the supramolecular complex 4 has been synthesized. In this complex, a ruthenium(II) tris-bipyridine type photosensitizer has been linked to a manganese(II) dimer via a substituted l-tyrosine, which bridges the manganese ions. The trinuclear complex 4 was characterized by electron paramagnetic resonance (EPR) and electrospray ionization mass spectrometry (ESI-MS). The excited state lifetime of the the ruthenium tris-bipyridine moiety in 4 was found to be about 110 ns in acetonitrile. Using flash photolysis in the presence of an electron acceptor (methylviologen), it was demonstrated that in the supramolecular complex 4 an electron was transferred from the excited state of the ruthenium tris-bipyridine moiety to methylviologen, forming a methylviologen radical and a ruthenium(III) tris-bipyridine moiety. Next, the Ru(III) species retrieved the electron from the manganese(II/II) dimer in an intramolecular electron transfer reaction with a rate constant kET>1.0x107 s-1, generating a manganese(II/III) oxidation state and regenerating the ruthenium(II) photosensitizer. This is the first example of intramolecular electron transfer in a supramolecular complex, in which a manganese dimer is covalently linked to a photosensitizer via a tyrosine unit, in a process which mimics the electron transfer on the donor side of PS II.}}, author = {{Sun, Licheng and Raymond, Mary Kartherine and Magnuson, Ann and LeGourriérec, Denis and Tamm, Markus and Abrahamsson, Malin and Huang, Ping and Mårtensson, Jerker and Stenhagen, Gunnar and Hammarström, Leif and Styring, Stenbjörn and Åkermark, Björn}}, issn = {{1873-3344}}, keywords = {{Electron transfer; Artificial photosynthesis; Manganese dimer complexes; Ruthenium complexes; Photosystem II}}, language = {{eng}}, number = {{1}}, pages = {{15--22}}, publisher = {{Elsevier}}, series = {{Journal of Inorganic Biochemistry}}, title = {{Towards an artificial model for Photosystem II: a manganese(II,II) dimer covalently linked to ruthenium(II) tris-bipyridine via a tyrosine derivative}}, url = {{http://dx.doi.org/10.1016/S0162-0134(99)00200-7}}, doi = {{10.1016/S0162-0134(99)00200-7}}, volume = {{78}}, year = {{2000}}, }