Mechanism of Action of Tetrocarcin A

Abstract

Tetrocarcin A strongly inhibited incorporation of ¹⁴C-uracil and ¹⁴C-D-glucosamine into B. subtilis in vivo. It had no effect on PM2 DNA in vitro. It caused 50% inhibition of DNA dependent RNA polymerase from E. coli at a concentration of about 0.1mM, while B. subtilis RNA polymerase was inhibited only 20-30% at a concentration of 0.08 μm and the degree of inhibition did not increase at a higher concentration.
The fact that inhibition of RNA synthesis was abolished in permeabilized cells of B. subtilis and leakage of cellular constituents was caused by tetrocarcin Asuggests that RNA synthesis is not the primary target and cell membrane is affected by tetrocarcin A in B. subtilis.