Printed in Great Britain 285 The Relation of Erythritol Usage to Virulence in the Brucellas

Erythritol stimulated the growth of virulent strains of Brucella abortus more than that of attenuated strains. No similar correlation existed between virulence and response to erythritol with strains of B. meliternis and B. suis; these were stimulated indiscriminately by erythritol. Erythritol was not detected in extracts of bovine white blood cells and hence is unlikely to be connected with the primary invasive process of intraphagocytic survival and growth of B. abortus. However, ultrafiltrates from extracts of bovine white blood cells stimulated the growthof B. abortus in laboratory media