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S Hayano

Publications and source records attributed to S Hayano.

49 records · Page 3Linked to original sources

Streptococcal sialidase. II. Kinetic and immunological studies of sialidase produced by group K streptococcus.

Kinetic and immunological studies were carried out on the sialidase produced by strain 6646, group K streptococcus (K-sialidase). The K(m) values of K-sialidase were 0.9 mm for sialyllactose and 0.17 mm for bovine submaxillary mucin. The antibody against K-sialidase was produced in rabbits immunized with this enzyme. An assay procedure for determination of the anti-K-sialidase activity in terms of reciprocal of the serum dilution corresponding to the 50% inhibition point is described. Anti-K-sialidase activity is widely distributed in human sera, but this has not yet been found to be correlated with streptococcal diseases, and no definite relationship was proved between the anti-K-sialidase titer and the anti-streptolysin O titer through this study. Anti-K-sialidase serum had no effect on Vibrio cholerae sialidase.

Animals↗

Streptococcal sialidase. I. Isolation and properties of sialidase produced by group K Streptococcus.

A survey has been made of the activity of a wide variety of standard strains of streptococci against bovine submaxillary mucin. Strain 6646 (group K) and strain D 168A "X" (group M) completely broke down and strain H 60R (group F) incompletely broke down bound sialic acid of bovine submaxillary mucin added to the growth medium. Among these strains, strain 6646 (group K) produced sialidase in the cell and in the culture fluid. An appropriate amount of glucose in the culture medium stimulated growth and the production of enzyme, but an excess of glucose in the culture medium caused abundant growth without production of the enzyme. The streptococcal sialidase was precipitated from the culture fluid by ammonium sulfate at 50% saturation, and further purification was achieved by diethylaminoethyl cellulose chromatography. Ca(++) and Co(++) stimulated the sialidase activity, and Mn(++), Zn(++), and ethylenediaminetetraacetate inhibited it. With acetate buffer, the optimal pH lay between 5 and 6. Sialic acid was detected in the reaction product of the streptococcal sialidase and bovine submaxillary mucin.

Cellulose↗