Leukocyte sialidase

Regarding the effect of Ca + on the activity of lysosomal enzymes, conflicting results have been reported in the literature. Ca + has been reported to have no effect on the activity of the enzyme from rat mammary gland (Tulsiani and Carubelli, 1971), rat liver (Miyagi and Tsuiki, 1984), or rat brain (Miyagi et aL, 1990a), but, at a concentration of 1 mM, slightly stimulates sialidase activity in human leukocytes (Schauer and Wember, 1984) and human liver (Michalski et... 

In studies with other systems, Glick et al. (1971) found sialidase, active toward fetuin, to be enriched in the lysosomal fraction of L cells Tulsiani and Carubelli (1971) found sialidase, active toward sialyllactose, not only enriched in lysomes isolated from rat mammary glands, but also in the soluble fraction Gielen et al. (1973) found a membrane-bound sialidase in leukocytes that was very active toward glycoproteins in the leukocyte homogenate and Bosmann (1974) found sialidase activity associated with the plasma membranes of human erythrocytes. Recently, Kishore et al. (1975) have reported the presence of a sialidase in Golgi isolated from rat liver. 

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