Abstract
The binding of the semiquinone to its two position (proximal and distal) in the QB site of the bacterial photosynthetic reaction center of Rhodobacter sphaeroides, was studied using continuum electrostatics. Experimental determined populations of the semiquinone in the proximal positions could be reproduced. Residues influencing either the binding of the semiquinone or the popluation of the semiquinone in the proximal position, could be identified. Both, the population and the binding of the semiquinone to the QB site is coupled to the protonation state of AspL213, which is located in direct vicinity of the semiquinone. Our results show, that a protonated AspL213 stabilizes the binding of the semiquinone and it favors the proximal position.
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© 2008 Springer Science + Business Media, B.V.
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Krammer, EM., Ullmann, G.M. (2008). The Role of AspL213 for Stabilizing Semiquinone Binding to the Photosynthetic Reaction Center. In: Allen, J.F., Gantt, E., Golbeck, J.H., Osmond, B. (eds) Photosynthesis. Energy from the Sun. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-6709-9_29
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DOI: https://doi.org/10.1007/978-1-4020-6709-9_29
Publisher Name: Springer, Dordrecht
Print ISBN: 978-1-4020-6707-5
Online ISBN: 978-1-4020-6709-9
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