Biological organisms electron transfer, location

Electron transfer (ET) is a key reaction in biological processes such as photosynthesis and respiration [1], Photosynthetic and respiratory chain redox proteins contain one or more redox-active prosthetic groups, which may be metal complexes or organic species. Since it is known from crystal structure analyses that the prosthetic groups often are located in the protein interior, it is likely that ET in protein-protein complexes will occur over large molecular distances ( > 10 A) [2-4],... 

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