EFFECT OF TEMPERATURE ON THE CELL-FREE PROTEIN-SYNTHESIZING SYSTEM IN PSYCHROPHILIC AND MESOPHILIC BACTERIA

[摘要] Temperature-dependency of poly(U)-directed polyphenylalanine synthesis was examined with different cell-free systems of Vibrio sp. strain ABE-1, a psychrophile, and Pseudomonas aeruginosa, a mesophile. In S-30 fractions, the activity of V. ABE-1 was higher than that of P. aeruginosa at and below 25°, but the activity of the former decreased rapidly above 25° and was completely lost at 40°. In ribosome-supernatant systems, V. ABE-1 ribosomes, especially 50S subunits, served a cold-stabilizing function, but V. ABE-1 supernatant was remarkably thermolabile, which was probably attributable to thermo-inactivation of phenylalanyl-tRNA synthetase present in the supernatant. V. ABE-1 ribosomes had no activation factor able to be released by washing with 1M NH4Cl.

[学科分类] 微生物学和免疫学