Studies on the induction of permeability in Ascaris lumbricoides eggs.

The initial process in the hatching mechanism of Ascaris eggs is the sudden onset of permeability in the previously impermeable ascaroside membrane. During this change the ascaroside membrane remains intact and no chemical changes can be detected. Using the molecular probe 1-anilino-8-naphthalene sulphonic acid no conformational changes were detected in the ascaroside membrane during the induction of permeability. It is suggested that either the permeability change is due to a very localized chemical or conformational change, not detectable by conventional analytical techniques, or the change is due to mechanical damage of the ascaroside membrane, brought about by the activity of the infective larva.