THE EFFECT OF TEMPERATURE SHIFTS ON PROTEIN-SYNTHESIS BY THE PSYCHROPHILIC BACTERIUM VIBRIO SP STRAIN-ANT-300

In the psychrophilic bacterium Vibrio sp. strain ANT-300, the temperature-related characteristics of protein synthesis in cells grown at 0-degrees-C differed from those of cells grown at 13-degrees-C. Cells grown at 0-degrees-C and 13-degrees-C transported amino acids at the same rates, dependent on the temperature at which rates were measured. The rates of protein synthesis in extracts of cells grown at 0-degrees-C and at 13-degrees-C differed, as a result of the changes in the properties of the soluble fraction involved in protein synthesis. Concurrently, levels of more than 24 polypeptides in the soluble fraction changed considerably. These results suggest that the difference in temperature dependence of protein synthesis in cells grown at various temperatures may be brought about by specific changes in the levels of a small number of polypeptides (less than 15% of the total number of proteins detected by silver-staining) in response to a change in temperature.