Esterification, of phosphates

Oxidative phosphorylation has been observed in particles derived from both bacteria and plants in addition to those derived from animal cells. A special type of oxidative phosphorylation has been found in photosynthetic organisms. Particles that contain the photochemical apparatus also appear to contain a series of enzymes that can recombine the products of photolysis and couple this process with the esterification of phosphate. The photochemical system is distinct from more conventional oxidative enzymes that use molecular oxygen as an electron acceptor. 

Inorganic phosphate is not required for levan synthesis, and it has no effect on the rate of reaction no esterification of phosphate can be detected. It is therefore considered that levan synthesis is the result of the transfer of fructose units from sucrose to a suitable acceptor through the mediation of a fructose-enzyme complex. 

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