Inhibitors of protein synthesis block action of cholera toxin

Prior treatment of macrophages with cycloheximide blocked the activation of adenylate cyclase by choleragen. The effect of cycloheximide was time and dose dependent and also caused by puromycin. Toxin receptors and the catalytic and regulatory components of the cyclase were still present. As degradation and generation of the A₁ subunit of choleragen was also blocked, we propose the existence of a membrane component that mediates the translocation of choleragen across the membrane.