Kininase production by some microbes.

kininase activity. Portions of sediment were examined for kininase activity after ultrasonic treat- ment, and the activity then revealed has been designated " Kininase activity in microbes." The portions of sediment which were exposed to ultrasonic treatment were obtained from 5 ml. samples from the cultures. The sediments were first washed three times in 0.9% saline, and then suspended in 5 ml. of a 0.02 M Na-phosphate buffer of pH 7.5. The ultrasonic treatment was then carried out with an MSE ultrasonic disintegrator at 20,000 c/s. This treatment was applied for five periods of 1 min each and under cooling in order to avoid increase in temperature. This amount of ultrasonic treatment resulted in maximal kininase activity from the microbes. The supernatants from the centrifuged portions of microbial cultures were investigated before and after adjustment of the pH to 7.5. If the kininase activity in the supernatant equalled more than 1 u./ml. dilution with 0.02 M Na-phosphate buffer of pH 7.5 was carried out before further tests on kininase activity were performed.