Isoenzyme activities of different strains of Cryptosporidium parvum

Different isoenzyme activities have been assayed in three strains of Crypto sporidium parvum, C1 (C. parvum from infected calves, UK), C2 (C. parvum fr om infected calves, Egypt) and C3 (C. parvum from infected goats, Egypt). T he electrophoretic variations of five enzymes; lactate dehydrogenase (LDH), glucose phosphate isomerase (GPI), hexokinase (HK), malate dehydrogenase ( MDH) and glutamate dehydrogenase (GLDH) were compared among the three diffe rent isolates using native polyacrylamide gel-electrophoresis. LDH showed a n identical pattern in the three isolates. GPI showed two different bands i n C3 and C1, with both bands present in C2. HK activity showed a weak band in C1 but no reaction was detected with C2 and C3. Malate dehydrogenase (MD H) showed no reaction in C1, but similar bands in C2 and C3. Glutamate dehy drogenase (GLDH) showed two different patterns, C2 and C3 had one pattern a nd C1 showed additional zones of reaction. Rat liver homogenate was run at the same time as the parasite extracts as a positive control. This investig ation suggests that GPI, HK and GLDH could be used to characterise differen t Cryptosporidium isolates. (C) 1999 Elsevier Science B.V. All rights reser ved.