The cytochrome f–plastocyanin complex as a model to study transient interactions between redox proteins

Abstract

Transient complexes, with a lifetime ranging between microseconds and seconds, are essential forbiochemical reactions requiring a fast turnover. That is the case of the interactions between proteinsengaged in electron transfer reactions, which are involved in relevant physiological processes suchas respiration and photosynthesis. In the latter, the copper protein plastocyanin acts as a solublecarrier transferring electrons between the two membrane-embedded complexes cytochromeb6fand photosystem I. Here we review the combination of experimental efforts in the literature tounveil the functional and structural features of the complex between cytochromefand plastocya-nin, which have widely been used as a suitable model for analyzing transient redox interactions.