Separation of antigenic glycoprotein fractions from cell-free homogenate of Pseudomonas pseudomallei and characterization as tyrosine phosphatase.

Cell-free extracts were prepared from Pseudomonas pseudomallei cells by freezing-thawing, sonication, and differential ultracentrifugation. The extracts were subjected to column chromatography with DEAE-sepharose to obtain glycoprotein fractions. The fractions showed acid phosphatase activity to p-nitrophenyl phosphate, tyrosine phosphate, serine phosphate, but not to threonine phosphate. They were highly antigenic when tested by immunofluorescence assay with the sera of melioidosis patients.