Inhibition of Growth, Synthesis, and Permeability in Neurospora crassa by Phenethyl Alcohol

Abstract

Lester, Gabriel (Reed College, Portland, Ore.). Inhibition of growth, synthesis, and permeability in Neurospora crassa by phenethyl alcohol. J. Bacteriol. 90: 29–37. 1965.—Inhibition of the growth of Neurospora crassa in still culture was detected at 0.05% and was complete at a level of 0.2% phenethyl alcohol (PEA). Benzyl alcohol was less inhibitory, and 3-phenyl-1-propanol and phenol were more inhibitory, than PEA; benzylamine and phenethylamine were less inhibitory than the analogous hydroxylated compounds. Inhibition by PEA was not reversed by synthetic mixtures of purines and pyrimidines or vitamins, or by casein digests, yeast extract, or nutrient broth. The germination of conidia was inhibited by PEA, but after an exposure of 8.5 hr no loss of viability was observed. The addition of PEA to growing shake cultures caused a simultaneous inhibition of growth and of the syntheses of ribonucleic and deoxyribonucleic acids and protein; the relationships of these compounds to mycelial dry weight and to one another were constant in growing mycelia, and PEA did not significantly affect these relationships. PEA partially inhibited the uptake of glucose, but severely restricted the accumulation of l -leucine, l -tryptophan, or α-aminoisobutyric acid in germinated conidia. The efflux of α-aminoisobutyric acid from germinated conidia was somewhat enhanced by PEA, but this effect was not so pronounced as the (complete) inhibition of α-aminoisobutyric acid accumulation by PEA. It is suggested that PEA affects primarily the initial influx of α-aminoisobutyric acid rather than the subsequent retention of α-aminoisobutyric acid.