Final answer:
Kinases transfer phosphate groups to substrates and are often involved in ATP generation. Phosphorylases add inorganic phosphate without using ATP, although their classification overlaps with kinases. Phosphatases remove phosphate groups, playing a key role in cellular regulation.
Step-by-step explanation:
Kinases are enzymes that catalyze the transfer of phosphate groups to various substrates, typically using ATP as a phosphate donor. An example within glycolysis is phosphoglycerate kinase, which transfers a phosphate group from 1,3-bisphosphoglycerate to ADP, forming ATP. Phosphorylases, on the other hand, add inorganic phosphate to substrates without using ATP. However, this term is not widely used in this context, as most reactions involving the addition of inorganic phosphate are classified under kinase activity.
Meanwhile, phosphatases remove phosphate groups from their substrates, catalyzing dephosphorylation reactions. These enzymes play crucial roles in multiple cellular processes, including signal transduction and metabolism. For instance, in glycolysis, the enzyme pyruvate kinase is involved in the dephosphorylation of phosphoenolpyruvate to form pyruvate.
In summary, kinases add phosphate groups to substrates, while phosphatases remove them. The use of the term phosphorylase is less standardized, and many of the reactions it describes are typically kinase activities that involve the transfer of phosphate groups with concomitant ATP synthesis or usage.