Modulation of EGF receptor autophosphorylation by alpha-hemolysin of Staphylococcus aureus via protein tyrosine phosphatase.

In the presence of assembled alpha-hemolysin (alpha-HL) of Staphylococcus aureus, the epidermal growth factor receptor (EGFr) is rapidly dephosphorylated. Several obvious possibilities that otherwise would have contributed to the dephosphorylation were ruled out. Instead, an elevation in the activity of a protein tyrosine phosphatase appears to be responsible for the observed loss of phosphorylation signal of EGFr. For this dephosphorylation, the assembly of alpha-HL is necessary while lytic pore formation is not required. In summary, the EGFr is unable to retain its phosphorylation signal in the presence of alpha-HL and the process is irreversible.