Human placental sialidase: partial purification and characterization.
A sialidase [EC 3.2.1.18] has been partially purified from human placenta by means of procedures comprising Con A-Sepharose adsorption, ammonium sulfate precipitation, sucrose density gradient centrifugation, and high-pressure liquid chromatography on a Shim pack Diol 300 column. On high-pressure liquid chromatography, most of the beta-galactosidase that comigrated with the sialidase on sucrose density gradient centrifugation was removed. The sialidase was purified 3,600-fold from the preparation obtained by Con A-Sepharose adsorption. The enzyme liberated the sialic acid residues from (alpha 2-3) and (alpha 2-6) sialyllactose, colomic acid, fetuin, and transferrin, but not from bovine submaxillary mucin. The enzyme also hydrolyzed gangliosides GM3, GD1a, and GD1b in the presence of sodium cholate as a detergent, but GM1 and GM2 were less susceptible to the enzyme. The optimum pHs for 4-methylumbelliferyl-N-acetylneuraminate, sialyllactose, fetuin, and GM3 lay between 4.0 and 5.0.
Hiraiwa
M
M
Department of Health Chemistry, Niigata College of Pharmacy.
Uda
Y
Y
Nishizawa
M
M
Miyatake
T
T
D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D004789:Enzyme Activation; D005260:Female; D006801:Humans; D007700:Kinetics; D009439:Neuraminidase / Q000302:isolation & purification* / Q000378:metabolism; D010920:Placenta / Q000201:enzymology*; D013379:Substrate Specificity
D009439:Neuraminidase