Phosphotransferase Volume

Phosphotransferases and nucleotidyltransferases were last reviewed in this series 15 years ago in Volumes VIII and IX. At that time a major mechanistic question was whether these enzymes catalyze their reactions by single-displacement or double-displacement mechanisms. The two mechanisms differed chemically with respect to whether the phosphoryl or nucleotidyl group is transferred directly between two substrates, or whether the group transfer is mediated by a nucleophilic group of the enzyme in a two-step mechanism via a covalent phos-phoenzyme or nucleotidyl-enzyme. 

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