Staphylococcal lactose phosphoenolpyruvate-dependent phosphotransferase system: site-specific mutagenesis on the lacE gene gives evidence that a cysteine residue is responsible for phosphorylation.
The lactose-specific phosphocarrier protein enzyme II of the bacterial phosphoenol-pyruvate-dependent phosphotransferase system of Staphylococcus aureus was modified by site-specific mutagenesis on the corresponding lacE gene in order to replace the histidine residues 245, 274 and 510 and the cysteine residue 476 of the amino acid sequence with a serine residue. The wild-type and mutant genes were expressed in Escherichia coli and the gene products were characterized in different in vitro test systems. In vitro phosphorylation studies on mutant derivatives of the lactose-specific enzyme II led to the conclusion that cysteine residue 476 is the active-site for phosphorylation of this enzyme II by a phospho-enzyme III of the same sugar specificity. A cysteine residue phosphorylated intermediate was first postulated for the mannitol-specific enzyme II of E. coli and studies performed independently concerning the lactose-specific enzyme II of Lactobacillus casei are in agreement with the above results.
Finkeldei
U
U
Abteilung Biologie der Ruhr, Universität Bochum, Germany.
Hengstenberg
W
W
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics*; D001483:Base Sequence; D003545:Cysteine; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000737:chemistry / Q000235:genetics*; D010750:Phosphoproteins / Q000737:chemistry / Q000235:genetics*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D013211:Staphylococcus aureus / Q000201:enzymology* / Q000235:genetics
D001426:Bacterial Proteins; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C029022:phosphoenolpyruvate-lactose dependent phosphotransferase system; D003545:Cysteine