METABOLIC LABELING OF WILD AND LABORATORY SUBSPECIES OF THE TRICHOSTRONGYLE NEMATODE HELIGMOSOMOIDES-POLYGYRUS

The immunological, biochemical and taxonomic relationship between wild and laboratory subspecies of Heligmosomoides polygyrus was studied by metabolically labelling parasite proteins with [S-35]-methionine. Muc h variability, both in content and synthesis of proteins was observed between the two subspecies. Laboratory female worms had a higher prote in content and incorporated more radioactive label into somatic protei ns than their wild counterparts. Incorporation of radioactivity into e xcretory/secretory (ES) proteins, predicted to contain important antig ens, demonstrates a major reduction in synthesis of proteins with mole cular weights 66, 55, 43, 41, 40, 39, 37, 28 and 16 kDa by laboratory females. These differences in protein synthesis might explain the diff ering infectivities of the two subspecies when passaged in inbred labo ratory (Mus musculus) and wild (Apodemus sylvaticus) mice.