ISOLATION OF FASCIOLA-HEPATICA HEMOGLOBIN

A haemoprotein released in vitro by adult Fasciola hepatica was purifi ed by gel filtration chromatography on Sephacryl S-200 and ion-exchang e chromatography on DEAE-Sepharose. The molecule, with an apparent mol ecular weight of > 200 kDa, contains a haem group and has absorption s pectra characteristics similar to haemoglobins. N-terminal amino acid sequence analysis revealed no similarity between the F. hepatica haemo globin and other vertebrate or invertebrate haemoglobins. Antibodies t o the haemoglobin molecule can be detected in the sera of F. hepatica- infected bovines as early as 1 week after infection.