Inhibition of protein biosynthesis in Escherichia coli B by tri-L-ornithine.

TLDR: The treatment of E. coli B cells with triornithine impaired the protein biosynthetic system of the treated cells in vitro, and the biological activity of the ribosomal fraction is impaired within the bacterial cell.

Abstract: 1 Triornithine completely inhibited growth of Escherichia coli B in the minimal liquid medium M63. The di-, tetra- and pentapeptides showed no effect on the growth of the bacterium. 2 Triornithine, when added to a bacterial culture, inhibited the incorporation of 14C-labeled amino acids into the protein fraction, but did not suppress the incorporation of [3H]uridine and [3H]thymidine. 3 The tripeptide inhibited translation of the induced β-galactosidase mRNA and also inhibited the synthesis of alkaline phosphatase initiated by derepression. 4 Triornithine had no effect on the reaction in vitro of T4-DNA-directed RNA synthesis. 5 Incubation of E. coli B cells with triornithine impaired the protein biosynthetic system of the treated cells in vitro. By this treatment the biological activity of the ribosomal fraction is impaired within the bacterial cell. 6 Triornithine, even at a high concentration, did not inhibit in vitro the polypeptide synthesis in a cell-free system.