Extracellular protein A from a methicillin-resistant strain of Staphylococcus aureus

Protein A has been isolated from a methicillin-resistant strain of Staphylococcus aureus, A676, which produces only extracellular protein A. The material is homogeneous after a one-step separation and has a molecular weight of 41000. Its physicochemical and immunochemical properties have been studied.