The Effect of Azide on Phototaxis in <i>Chlamydomonas reinhardi</i>

Abstract

Phototaxis in Chlamydomonas reinhardi was specifically inhibited by azide. The effect of azide was rapid and reversible, and did not depend upon the intensity of actinic light. Under conditions of completely inhibited phototaxis, azide had no effect on the number of motile cells in the population or on the rate of motility. The effect was not related to changes in oxygen uptake or cellular ATP concentration. Apparently, a cellular component or process specifically involved in phototaxis is inactivated by azide.