SEROLOGICAL AND BIOCHEMICAL-PROPERTIES OF THE MAJOR OUTER-MEMBRANE PROTEIN WITHIN STRAINS OF THE GENUS ACTINOBACILLUS

Sarcosyl-extracted outer membrane preparations of organisms of the gen us Actinobacillus were investigated with regard to heat-modifiable and serological properties as well as N-terminal amino acid sequencing of the isolated major outer membrane protein (Omp). The major Omp of Act inobacillus lignieresii was recognized by a monoclonal antibody with s pecificity towards Proteus mirabilis OmpA. Moreover, N-terminal amino acid sequencing revealed strong homology to OmpA of enterobacteriaceae , on the contrary, no reaction of the Proteus mirabilis OmpA monoclona l antibody was detectable when investigating the outer membrane prepar ations of Actinobacillus suis and Actinobacillus equuli in Western blo t analyses. N-terminal amino acid sequencing of the major Omp of these two species showed homologies to OmpC or OmpF of the enterobacteriace ae. In accordance with these results, a polyclonal antibody with speci ficity for the major Omp of Pasteurella multocida cross-reacted with t he major Omps of Actinobacillus suis and Actinobacillus equuli. The re lationship of the major Omp of Pasteurella multocida and OmpC and OmpF had been verified in recent studies.