Partial purification of the aggregation pheromone nippolure from female Nippostrongylus brasiliensis (Nematoda)

Partial purification of a pheromone of the zooparasitic nematode Nippostrongylus brasiliensis was achieved. The polypeptide pheromone is degraded by Pronase while increased recovery is obtained after treatment with the protease inhibitors phenylmethylsulfonyl fluoride or l-1-tosylamide-2-phenylethyl chloromethyl ketone. The pheromone has a net negative charge, based on retention on DEAE cellulose and an approximate isoelectric point of 7.3. A combination of double treatments with phenylmethylsulfonyl fluoride and gel filtration enables storage up to nine days which yields biological activity similar to fresh, untreated chromatographic fractions.