[Protein A-activity of Staphylococcus hyicus in comparison to protein A of Staphylococcus aureus (author's transl)].

Protein A (PA)-Activity was demonstrated in 44 (93.6%) of 47 Staphylococcus hyicus-cultures. PA from S. hyicus, as well as PA from S. aureus, could be released by extraction with concentrated formic acid or by treatment of the staphylococci with lysostaphin. PA was also demonstrable in the culture medium. Purification of PA from S. hyicus and S. aureus could be achieved by affinity-chromatography on IgG-Sepharose. In Ouchterlony-tests both PA-preparations gave single lines of identity with normal sera from man, pig, dog and guinea pig (Fig. 1). Immunoelectrophoretic analysis indicated a significantly faster migration towards the anode for PA from S. hyicus than PA from S. aureus (Fig. 2). Isoelectric focusing revealed maximal activity for PA from culture supernatant of S. hyicus about pH 4.3 and for that of S. aureus at pH 5.0 (Fig 3). Gelchromatographic experiments indicated a lower molecular weight for PA from S. hyicus than for PA from S. aureus (Fig. 4).