Function
Phosphocarrier protein HPr (HPr) is a component of the sugar phosphotransferase system. The system catalyses the phosphorylation of sugars during their translocation across cell membrane. A phosphoryl group is transferred from phosphoenolpyruvate via several enzymes (EI, EII) to HPr[1]. A conserved histidine in the N terminal of HPr is the acceptor of the phosphate. In Gram-positive bacteria HPr there is a conserved serine which is phosphorylated.
Phosphocarrier protein NPr (NPr) is a component of the sugar phosphotransferase system. NPr is a phosphoryl transfer protein, homologous to HPr which functions to regulate nitrogen metabolism[2].
Phosphocarrier protein III Glc (PcpIII) is a signal-transducing component of the phosphoenolpyruvate:glycose phosphotransferase system of E. coli[3].
Structural highlights
The prohibits the HPr to act as a phosphocarrier in the EI reaction[4].
3D structures of phosphocarrier protein HPr
Phosphocarrier protein HPr 3D structures
