Coenzyme phosphorolysis

Group transfer enzymatic transfer of a functional group from one molecule to another (Table). Coenzymes (see) often serve as carriers of the groups, hence the term transport metabolites . Hydrolysis and phosphorolysis can be regarded as special cases of G.t. in which the group is transferred to water or a phosphate ion. 

Since thiol estem are the immediate end products of various oxidative reactions, the phosphorolysis of these intermediates constitutes a mechanism by which the sulfhydryl enzymes and coenzymes involved are constantly regenerated with the simultaneous formation of more generally useful energy-rich acyl-phosphate compounds. In the presence of specific enzymes the phosphoryl groups of the acyl phosphates are transferred to ADP with the formation of ATP. For example, many bacteria contain an enzyme that catalyzes the synthesis of ATP by a reaction between acetyl-P and ADP [reaction (15)]. The enzyme catalyzing this reaction... 

Another compound which undergoes phosphorolysis is nicotinamide riboside, a component part of the pyridino-coenzymes. It is apparently split by the same enzyme which acts on inosine. Thus, the ratio of enzymatic activities against inosine and nicotinamide riboside has been found to remain constant during the course of purification of hog liver fractions, and inosine inhibits the splitting of nicotinamide riboside competitively. The phosphorolysis can be represented as follows ... 

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