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

Research has been conducted on the proton transfer pathway to Q (sub)B. The study of this pathway in the reaction center from Rhodobacter sphaeroides has been carried out and the results demonstrate that the binding of Zn (super)2+ or Cd (super)2+ to the reaction center surface at His-H126, His-H128 and Asp-H124 inhibits the proton transfer rate to Q (sub)B.