INVESTIGATIONS ON THE PROTEINS FROM THE O UTER-MEMBRANE OF PASTEURELLA .1. COMMUNICATION - POLYACRYLAMIDE-GEL ELECTROPHORESIS OF OUTER-MEMBRANE PROTEINS AS A POSSIBILITY FOR DIFFERENTIATION OF PASTEURELLA-HAEMOLYTICA STRAINS

Using the sodium laurylsarcosinate method, outer membrane proteins (OM Ps) of 63 Pasteurella haemolytica strains an isolated and their protei n patterns obtained by SDS polyacrylamide gel electrophoresis (SDS-PAG E) are compared. A high degree of similarity became evident both withi n A and T biotypes in the molecular weight range of 25 to 50 KDa. Stai n-to-strain variations are mainly limited to quantitative differences in individual protein bands. It is concluded that within both the A an d T biotype groups equal sets of major proteins are present with diffe ring amounts of individual constituents. Biotypes A and T can be clear ly distinguished on the basis of marked variations in OMP profiles. OM Ps of those AT strains included in comparative studies are exhibiting no general homogeneity, but a relative heterogeneity due to different protein compositions, which are, however, clearly distinct from the pa tterns of biotypes A and T. It is established unambiguously that isola tes belonging to biotypes A or T, as well as AT strains, can be clearl y distinguished from each other on the basis of SDS-PAGE analysis of O MP extracts. Thus, polyacrylamide gel electrophoresis of outer membran e proteins can be used for differentiation.