The Synthesis of Heat-shock Proteins after a Decrease in Translational Capacity in Escherichia coli

Various conditions which decrease translational capacity and enhance the synthesis of ribosomal components were analysed with respect to the synthesis of heat-shock proteins in Escherichia coli: (a) deprivation of streptomycin from a streptomycin-dependent mutant, (b) addition of tetracycline to a partially tetracycline-resistant strain, and (c) nutritional shift-up conditions. In all cases, the rate of synthesis of the heat-shock proteins DnaK, GroEL and C62.5 decreased while the synthesis of ribosomal components increased. Thus inhibition of ribosome formation or a decrease in translational capacity do not induce the stress proteins, but have the opposite effect.