Purification and characterization of the HPR protein of Pediococcus halophilus

HPr protein, the ptsH gene product, of the phosphoenolpyruvate:sugar phosphotransferase system of Pediococcus halophilus was purified to homogeneity using heat and acid treatments, DEAE-Sepharose CL-6B and hydroxyapatite column chromatographies. The purified protein complemented the HPr activity of the phosphotransferase system in Staphylococcus aureus ptsH mutant cell lysate. The molecular weight was estimated as 6,500 by SDS polyacrylamide gel electrophoresis. The amino acid sequence of the amino-terminal part (1-44) of the native purified protein was highly homologous to those of HPr proteins from gram-positive bacteria. Antiserum raised against the purified HPr protein specifically reacted with the Pediococcus halophilus HPr protein and did not cross-react with Staphylococcus aureus or Escherichia coli HPr proteins.