No abstract

Cell suspensions of the psychrophilic bacterium, strain 82 produced the maximum amount of hydrogenase at 15C. No induction occurred at 25C and a limited amount of enzyme was formed at 0C. In comparison, mesophilic Escherichia coli and Aerobacter aerogenes produced maximum amounts of enzyme at 35C and 30C, respectively. No induction occurred at 10C.Psychrophilic Pseudomonas fluorescens produced maximum amounts of enzyme involved in benzoate oxidation at 25C and a large quantity of enzyme was produced at 5C. Induction did not occur at 35C or at 0C. In comparison, mesophilic Pseudomonas aeruginosa produced the largest amount of enzyme at 30C; induction did not occur at 45C or at 10C. Induction was most rapid for the psychrophile at 25C as contrasted to 35C for the mesophile.The data clearly show that the temperature range for induction of the above enzymes and for maximum enzyme formation is considerably lower in the psychrophiles than in the mesophiles.