Continuous culture of bacteriophage Q-beta using a cellstat with a bubble wall-growth scraper

Abstract
It has been shown that a virulent phage Qβ can be cultured continuously in a cellstat which was developed to culture a bacteriophage fd for the study of molecular evolution. A cloned disadvantageous mutant was cultured to obtain a biological relaxation curve to selection/mutation equilibrium. A new technique for scraping off the wall growth by air bubbles is introduced. The scraper worked well in short‐time cultivation of Qβ. It has various advantages of a closed system.