P680, or photosystem II primary donor, is the reaction-center chlorophyll a molecular dimer associated with photosystem II in plants, algae, and cyanobacteria...

plastoquinone: H 2O → P680 → P680* → plastoquinol Plastoquinol, in turn, transfers electrons to cyt b6f, which feeds them into PSI. The step H 2O → P680 is performed...

antenna complex, ending in the reaction center where specific chlorophylls P680 and P700 are located. Chlorophyll a is essential for most photosynthetic...

pheophytin, which then passes the electrons to a quinone (QA) in RC P870 and RC P680. The overall mechanisms, roles, and purposes of the pheophytin molecules...

pigment P680 at the core of photosystem II, which is transferred to the primary electron acceptor, pheophytin, leaving behind P680+. The energy of P680+ is...

molecule. The energy of the exciton is transferred to a chlorophyll molecule (P680, where P stands for pigment and 680 for its absorption maximum at 680 nm)...

is mostly localized on one chlorophyll center (70−80%). Because of this, P680+ is highly oxidizing and can take part in the splitting of water. Photosystem...

chlorophyll (P680+) is then reduced back to its ground state by accepting an electron stripped from water. The electron that reduces P680+ ultimately comes...

hydrogen electrode (SHE). At pH = 7, Ered = 1.23 – 0.059 V × 7 = +0.82 V P680+ +  e− → P680 ~ +1.0 Half-reaction independent of pH as no  H+ is involved in the...

that are part of larger supercomplexes known as P700 in Photosystem I and P680 in Photosystem II. The structures of these supercomplexes are large, involving...