Identification of the proton pathway in bacterial reaction centers: decrease of proton transfer rate by mutation of surface histidines at H126 and H128 and chemical rescue by imidazole identifies the initial proton donors.

@article{Adelroth2001IdentificationOT,
  title={Identification of the proton pathway in bacterial reaction centers: decrease of proton transfer rate by mutation of surface histidines at H126 and H128 and chemical rescue by imidazole identifies the initial proton donors.},
  author={Pia Adelroth and Mark L. Paddock and Ali Reza Tehrani and J. Thomas Beatty and George Feher and Melvin Y Okamura},
  journal={Biochemistry},
  year={2001},
  volume={40 48},
  pages={14538-46}
}
The pathway for proton transfer to Q(B) was studied in the reaction center (RC) from Rhodobacter sphaeroides. The binding of Zn(2+) or Cd(2+) to the RC surface at His-H126, His-H128, and Asp-H124 inhibits the rate of proton transfer to Q(B), suggesting that the His may be important for proton transfer [Paddock, M. L., Graige, M. S., Feher, G. and Okamura, M. Y. (1999) Proc. Natl. Acad. Sci. U.S.A. 96, 6183-6188]. To assess directly the role of the histidines, mutant RCs were constructed in… CONTINUE READING