SELECTIVE AND REVERSIBLE INHIBITION OF THE SYNTHESIS OF BACTERIAL DEOXYRIBONUCLEIC ACID BY PHENETHYL ALCOHOL

Abstract

The selective inhibitory effects of phenethyl alcohol on gram-negative bacteria were confirmed with a variety of species. At a concentration of 0.25%, phenethyl alcohol was bacteriostatic for gram-negative bacteria; gram-positive cells were unaffected. Pseudomonas fluorescens required higher concentrations of the compound for inhibition than did the other gram-negative bacteria, and the gram-positive acid-fast mycobacteria resembled the majority of gram-negative bacteria in sensitivity. In the presence of phenethyl alcohol, gram-negative cells formed long filaments. There was no net synthesis of deoxyribonucleic acid (DNA) in such cells, whereas protein and ribonucleic acid (RNA) syntheses were unaffected. Upon removal of phenethyl alcohol, multiplication of the cells immediately ensued with concomitant DNA synthesis. Yeast extract stimulated both RNA and protein synthesis in phenethyl alcohol-treated Escherichia coli, but no detectable stimulation of DNA synthesis occurred under these conditions.