The staphylococcal phosphoenolpyruvate-dependent phosphotransferase system. Purification and characterisation of the galactoside-specific membrane-component enzyme II.
The galactoside-specific membrane-bound component of the staphylococcal phosphoenolpyruvate-dependent phosphotransferase system, enzyme IIlac, was purified to homogeneity. The purification procedure involved several extractions steps at the particulate state, followed by solubilisation with Triton X-100. Up to this stage the biological activity of enzyme II was preserved. Isolation of the homogeneous protein involved gel filtration of the dodecylsulfate-denatured material. An apparent molecular weight of the polypeptide chain was estimated by dodecylsulfate gel electrophoresis. The 55000-Mr protein is visible in dodecylsulfate gels upon induction of the staphylococcal lac operon as a more intensively stained area. Antibodies against the denatured 55000-Mr protein inhibit the mutant complementation assay of enzyme II offered as membrane fragments. This demonstrates that the 55000-Mr protein and enzyme IIlac are identical. Polarity and the solubility of the protein in detergents are typical for an integral membrane protein.
D000596:Amino Acids / Q000032:analysis; D002855:Chromatography, Thin Layer; D004591:Electrophoresis, Polyacrylamide Gel; D005697:Galactosides / Q000378:metabolism; D007525:Isoelectric Focusing; D007763:Lac Operon; D008055:Lipids / Q000032:analysis; D008566:Membranes / Q000201:enzymology; D008970:Molecular Weight; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000302:isolation & purification*; D013211:Staphylococcus aureus / Q000201:enzymology*
D000596:Amino Acids; D005697:Galactosides; D008055:Lipids; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C029022:phosphoenolpyruvate-lactose dependent phosphotransferase system