In enzymology, a phosphoenolpyruvate-protein phosphotransferase () is an enzyme that catalyzes the chemical reaction
Thus, the two substrates of this enzyme are phosphoenolpyruvate and protein histidine, whereas its two products are pyruvate and protein Npi-phospho-L-histidine.
This enzyme belongs to the family of transferases, specifically those transferring phosphorus-containing groups (phosphotransferases) with a nitrogenous group as acceptor. This enzyme participates in phosphotransferase system (pts).
The systematic name of this enzyme class is phosphoenolpyruvate:protein-L-histidine Npi-phosphotransferase. Other names in common use include phosphoenolpyruvate sugar phosphotransferase enzyme I, phosphopyruvate-protein factor phosphotransferase, phosphopyruvate-protein phosphotransferase, sugar-PEP phosphotransferase enzyme I, and phosphoenolpyruvate:protein-L-histidine N-pros-phosphotransferase.