Effect of Chloramphenicol on Protein and Nucleic Acid Synthesis by Shigella flexneri

Abstract

SUMMARYResting organisms of Shigella jlexneri 3 were able to synthesize protein and nucleic acids in a chemically defined medium. Protein synthesis was markedly inhibited while ribonucleic acid (RNA) synthesis was stimulated by low concentrations of chloramphenicol ; deoxyribonucleic acid synthesis was inhibited slightly. Neither glycine, L-phenylalanine nor L-tyrosine annulled the action of the antibiotic. Inhibition of protein synthesis and stimulation of RNA synthesis in resting organisms of a chloramphenicol-resistant mutant of S. jexneri 3 was observed only in the presence of high concentrations of chloramphenicol. The results presented in this papcr show that chloramphenicol suppresses the growth of S . j l e x w i 3 by inttdering with the synt1,esis of protein. The stimulation of RNA synthesis suggests that chloramphenicol may exert its inhibitory action by promoting the formation of RNA with altered biological activity.

Effect of chloramphenicol on ribonucleic acid synthesis in liver cells in suspension

“…(i) When net increase in the amount of RNA was taken as a criterion of RNA synthesis, RNA was found to continue to be synthesized (often at enhanced rates) in the presence of chloramphenicol (Gale & Folkes, 1953;LePage, 1953;Wissemann, Smadel, Hahn & Hopps, 1954;Pardee & Prestidge, 1956;Hahn, Schaechter, Ceglowski, Hopps & Caik, 1957;Horiuchi, Sunakawa & Mizuno, 1958;Harrington, 1958;Bernlohr & Webster, 1958; Gros & Gros, 1958;Aronson & Spiegelman, 1961;Yee, Pan & Gezon, 1962;Hahn & Wolfe, 1962).…”