PURIFICATION AND CHARACTERIZATION OF SIALIDASE FROM PORCINE LIVER

Sialidase [E,C,3,2,1,18] has previously been purified from porcine liv er by procedures including extraction, ammonium sulfate precipitation, concanavalin A-Sepharose adsorption, activation, CM-Sepharose ion exc hange chromatography, and HPLC on a Shim pack Diol 300 column, Two sia lidase preparations, sialidase I and II, were obtained by CM-Sepharose column chromatography and were eluted with pH 4.5 and 5.0 buffers, re spectively, The two enzyme preparations showed the same optimum pH, pH stability, and specificities for natural substrates, The two final pr eparations contained B-galactosidase activity and showed three protein components of 64, 30, and 21 kDa with sodium dodecyl sulfate-polyacry lamide gel electrophoresis, which are derived from the P-galactosidase multimer, The anti-P-galactosidase multimer antiserum was able to pre cipitate sialidase activity. It is likely that porcine liver sialidase exists as a multienzyme complex with P-galactosidase and carboxypepti dase (protective protein).