Abstract
1. Chromomycin A3, an antibiotic and antitumor substance produced by Streptomyces griseus No. 7, inhibits the growth of B. subtilis cells while it permits the normal growth of E. coli cells.
2. The incorporation of inorganic P32 or C14-adenine into DNA or RNA by B. subtilis cells was extensively inhibited by the antibiotic. The inhibition of the uptake of S35-sulfate into protein fraction occurred much slower and might probably be due to the secondary effect resulting from the reduced RNA synthesis.
3. The chromatography of the nucleic acids on methylated albumin-kieselguhr column indicated that the inhibitory effect of the antibiotic is not confined to the particular species of cellular RNA's.
The authors would like to express their deep appreciation to Prof. N. Shimazono for his encourage-ment and valuable adviees.
