Recovery of Escherichia coli IFO3301 Injured by Glycine and Ethanol

Abstract

The recovery of Escherichia coli IFO3301 injured by glycine (Gly) and/or ethanol (Et) was investigated. After treatment with 0.39 M Gly (Gly_0.39) and 3 M Et (Et₃), cells recovered in VSHINSKY broth (V-broth) but were unable to grow in glycerol. Further, the recovery was delayed in the presence of 0.75 M Gly and 1 M Et (Et₁). In Et₁-injured cells, ammonium lactate was required to restore respiratory activity. The organic ingredients of V-broth rescued the respiratory activity of the injured cells in the presence of puromycin, chloramphenicol and sodium azide. Treatment with Et at 3 M stopped the respiratory activity completely in V-broth. The β-Galactosidase (β-Gal) activity of the cells decreased slightly after treatment with 0.26 M Gly or Et₁. Not only 2 M Et (Et₂) combined with Gly_0.26 but also Et₂ alone inhibited the β-Gal activity strongly. This indicated that Et inhibited the β-Gal induction more than Gly. The results suggested that Et plays a role in the prevention of protein synthesis and respiratory electron transport to inhibit bacterial growth.