“…The stimulation by hydroxystilbamidine of the RNA polymerase of Escherichia coli (Festy, 1971) is similar to that observed with diamines (Krakow, 1963;Weiss and Fox, 1964). Outside binding of these dibasic molecules would mimic in some way the role played by a new factor of regulation (H factor) of the initial step of RNA synthesis (Gros and Contesse, 1972).…”