GROUP-B STREPTOCOCCAL NEURAMINIDASE IS ACTUALLY A HYALURONIDASE

The extracellular group B streptococcal enzyme described in numerous r eports as a neuraminidase is really a hyaluronidase. Over the past 25 years, the enzyme was routinely assayed with bovine submaxillary mucin as the substrate and by the thiobarbituric acid procedure to measure released sialic acid. Characterization of the actual compound released by the enzyme revealed it to be an alpha,beta-unsaturated derivative of hyalobiuronic acid that was derived from hyaluronic acid contaminat ing the mucin preparation. Previous reports describing an association of elevated levels of extracellular neuraminidase with virulent strain s of group B streptococci must be reevaluated with the recognition tha t the enzyme is really a hyaluronidase.