Effect of an electric field on the motility of Entamoeba histolytica examined by multiple-beam interference microscopy

Joshi, N. V., Medina, H., and Tucci, P. 2001. Effect of an electric field o n the motility of Entamoeba histolytica examined by multiple-beam interfere nce microscopy. Experimental Parasitology 97, 179-185. A recently developed multiple-beam interference microscopic technique has been used to visualiz e submicroscopic structures of Entamocba histolytica and their movements in applied external electric fields. The movements were videorecorded and it was found that at low current (120 muA) pseudopods are filled with hyaline ectoplasm. At slightly higher current(about 150 muA), the amoeba stops exte nding the pseudopods and loosens its attachment to the surface. At higher c urrents (200 muA), it forms a cyst and remains immobile for a time. Before this stage is reached a narrow ring is formed around the nucleus due to alt erations in the proteins to protect it. (C) 2001 Academic Press.