Presence of N-Acetylneuraminate Pyruvate-Lyase Activity in Sialidase Producing Strains of Erysipelothrix rhusiopathiae and Oerskovia sp

The enzyme N-acetylneuraminate pyruvate-lyase (sialate aldolase) was found in two sialidase producing strains of the pathogen species Erysipelothrix rhusiopathiae and the saprophyte genus Oerskovia. The enzyme is secreted in the medium in both strains and its activity reaches similar values - 12.5 and 13.3 U/(mg protein) for E. rhusiopathiae B40 and Oerskovia sp./14 respectively. Intracellular enzyme activity of 10.7 U/(mg protein) was also detected in the latter strain. The data obtained for the sialate aldolase and sialidase activities were compared to analogical data for Vibrio cholerae and Aeromonas sp. sialidase producer strains. The presence of sialate aldolase and sialidase enzymes in all these strains supports the concept that sialic acid metabolism contributes to the pathogenesis of microorganisms.