Selective suppression of positive chemotaxis in Physarum polycephalum by treatment with rotenone or under anaerobic condition.

The chemotactic motive force of plasmodia of Physarum polycephalum was measured by the double-chamber method. The treatment of plasmodia with 0.1 mM rotenone did not affect the motility of the palsmodia but led to suppression of the chemotaxis toward all the attractants examined (glucose, galactose, c-AMP, KH2PO4). Rotenone treatment did not affect the chemotaxis against repellents (fructose, NaCl). Similar results were obtained when the chemotactic motive force was measured under an anaerobic condition (95% N2-5% CO2).