Redox-active amino acids molecular structure

Figure 2 Molecular structures and IUPAC numbering scheme of organic cofactors occurring in photosynthetic reaction centres (bRC, PS I, PS II). (Bac-teriolpheophytin is the free base of (bacterio)chlorophyll plastoquinone (PQ) is found in PS If phylloquinone or vitamin K, ( VK,) in PS I many bacteria contain ubiquinone (UQ). Shown is also the amino acid tyrosine (Tyr, Y) that is redox active in PS II.

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