Comparative electrophoretic and serological analyses of Vibrio comma and Aeromonas liquefaciens proteinases.

Abstract

The occurrence of one, or two, proteinase fractions was demonstrated for 5 strains of Vibrio comma using the zymogram technique for proteinases. Most of the proteinase fractions moved more or less rapidly towards the cathode, although some were shown to migrate in the opposite direction at pH 6.2. Serological cross reactions were observed between proteinase fractions produced by a strain of Aeromonas liquefaciens and 2 of the V. comma stvains examined. The proteinase A of Ae. liquefaciens was shown to be enzymoserologically identical, or closely related, to one of the proteinase fractions of V. comma, while no relationship was observed between the proteinase B of Ae. liquefaciens and any of the V. comma proteinases. In order to remove the naturally occurring proteinase inhibitors from the antiproteinase‐containing γ‐globulins in immune serum, precipitation with sodium sulphate was used, with success, as demonstrated by disc electrophoresis and the Casein Precipitation Inhibition test (CPI‐test). The need for suitable separation techniques when using enzymes as a basis for the taxonomical differentiation of the corresponding organisms is emphasized.