Synthesis of High-Energy Nucleotides

The free energy derived from biological oxidations is largely converted into chemical energy in the form of ATP, which is generally considered to be the most important mobile carrier of metabolically available energy in cells. 

At present, neither oxidative phosphorylation nor photophosphoryla-tion is completely understood. In oxidative phosphorylation, electrons are derived from substrates that enter the Krebs cycle and from fatty acids, whereas in photophosphorylation they are furnished by chlorophyll in the presence of light. ATP s3mtheas is coupled to the subsequent sue- 

Types of Substrate-Level Oxidative Phosphorylation Reactions 

H acceptors oxygen on C-2, flavin Aldehyde acceptor enzyme-thiamine-PP Acyl acceptor Pi Enzymes 2( ) 

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De novo synthesis of high-energy nucleotide sugars... 

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