Neuraminidase activity in Trypanosoma rangeli.
Supernatants of cultures and extracts of Trypanosoma rangeli readily release N-acetyl neuraminic acid from a variety of substrates. The activity in both supernatant and cell extract is precipitated between 30 and 50% ethanol, and between 40 and 70% ammonium sulfate. Fractionation of the culture supernatant by gel exclusion gives a single peak of neuraminidase activity of molecular weight 48 000. The culture supernatant releases sialic acid at different rates from the following substrates:fetuin, sialyllactose and orosomucoid but not from bovine submaxillary mucin and ovomucoid. The enzyme in the culture supernatant is also active against human erythrocytes of all ABO types. The enzyme showed an optimum pH of 5.0 for sialyllactose and erythrocyte substrates. Large amounts of the enzyme are preferentially secreted during growth in vitro.
D000818:Animals; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008970:Molecular Weight; D009439:Neuraminidase / Q000378:metabolism*; D013045:Species Specificity; D014345:Trypanosoma / Q000201:enzymology* / Q000254:growth & development
D009439:Neuraminidase