1994 Volume 57 Issue 1 Pages 82-83
We attempted to isolate hemagglutinins from P. intermedia strain E18 and to characterize their active fractions. Hemagglutination activities were found in three different fractions (designated as A, B and C) by sucrose density gradient ultracentrifugation. Electron microscopic study revealed that fraction A was an amorphous structure, while extracellular vesicles were a major constituent of fractions B and C. All fractions were sensitive to heat and proteolytic enzymes. However, the sensitivity pattern of fraction A was different from that of B and C. D-Glucosamine, D-galactosamine and N-acety-neuraminic acid caused hemagglutination inhibition of all fractions. In addition, fraction A was sensitive to L-arginine. These results indicate that at least two different hemagglutinins, which are proteins found in nature, may exist in P. intermedia strain E18.