Oocysts of Cryptosporidium parvum showed relatively low
levels of SOD activity. The SOD which had a pI of 4.8 and an approximate
molecular weight of 35 kDa appeared to be iron dependent. Catalase, glutathione
transferase, glutathione reductase and glutathione peroxidase activity
could not be detected, nor could trypanothione reductase. No NADH or NADPH
oxidase activity could be detected, nor could peroxidase activity be demonstrated
using o-dianisidine, guaiacol, NADPH or NADH as co-substrates.
However, an NADPH-dependent H2O2 scavenging system
was detected in the insoluble fraction.