Temperature Effects on the Ground State Absorption Spectra and Electron Transfer Kinetics of Bacterial Reaction Centers
It has been a general finding that the rates of many of the electron transfer processes in bacterial reaction centers are rather insensitive to temperature.1,2 In fact, often the rates actually increase slightly as the temperature is reduced. This is observed, for example, in Rb. sphaeroides reaction centers for electron transfer from P* to I (BPhL),3 from I− (BPhL −) to the primary quinone QA,4 and for the charge recombination reaction P+QA − → PQA.5–7 (P is the dimer of BChl molecules.) These findings have been taken to suggest that these reactions are activationless, or nearly so.
KeywordsBurning Glycerol Chlorophyll Recombination Ethylene Glycol
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