Hydrolytic photosynthesis

Proton transfer is a particularly important transport process. Beyond acid-base reactions, proton transfer may be coupled to electron transfer in redox reactions and to excited-state chemistry. It is of enormous significance in biochemical processes where it is an essential step in hydrolytic enzyme processes and redox reactions spanning respiration, and photosynthesis where proton motion is responsible for sustaining redox gradients. In relatively recent times, proton transfer in the excited state has undergone significant study, primarily fueled by advances in ultrafast spectroscopy. 

W. is a reactant in enzyme (hydrolase)-catalysed hydrolytic cleavage of macromolecules (proteins, carbohydrates, fats), representing the first stage in the biological degradation of these substances. W. is formed metabolically by the operation of the respiratory chain (Thble 3) (respiratory W.), and is the substrate of photosynthesis. 

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