The Effect of P-Chloromercuribenzoate on Amoeboid Movement, Flagellar Movement and Gliding Movement

The effect of p-chloromercuribenzoate (PCMB), a specific sulfhydryl reagent, upon several types of cellular motion—amoeboid movement, flagellar movement and gliding movement—was studied. 2. The effect of PCMB on the motions of different types is more or less identical: First, motion becomes sluggish; this is then followed by complete cessation at some particular concentration. Second, motion is restored completely or partially through subsequent application of cysteine in concentrations higher than those of the PCMB previously applied. Third, when the reactivity of PCMB upon -SH groups has been eliminated with cysteine in advance, PCMB exerts no effect the cellular motion. 3. From the fact that PCMB is bound to -SH groups with high specificity, it is reasonable to conclude that the cessation and recovery of the cellular motion are closely related to the blocking and liberation of -SH groups.