Using several single and double mutants in the d-e interhelical loop of D 1 protein in Synechocystis sp. PCC 6714, we have shown that a differential sensitivity of formate inhibition on the acceptor side of Photosystem II occurs in the following order: S264A-F255L > S264A = N266T > N266T-S264A > F255L = N266PD = WT ≫ N266T-A251V = A251V. On the basis of the absence of additivity of the effects between single and double mutants, it is concluded that the couples S264 and N266, N266 and A251, and S264 and F255 interact with each other in formate binding. It is considered highly likely that these effects are due to the modification, to some extent, of the overall conformation of the D 1 protein which, in turn, modifies the formate/bicarbonate binding at its site in the same protein. © 1995.
Vernotte, C., Briantais, J. M., Astier, C., & Govindjee. (1995). Differential effects of formate in single and double mutants of D 1 in Synechocystis sp. PCC 6714. BBA - Bioenergetics, 1229(2), 296–301. https://doi.org/10.1016/0005-2728(95)00018-E