Preparation of Phage-insensitive Strains of Tetragenococcus halophila and Its Application for Soy Sauce Fermentation.

We attempted to breed phage-insensitive strains of Tetragenococcus halophila D10. Phage contact during selection initially caused the occurrence of lysogeny. Subsequently, we screened phage-insensitive mutants by replica plating so that mutant cells did not touch the phage during selection. Two strains were selected from about 150,000 strains. They grew normally in soy sauce mash (moromi) in the presence of phage φD-10, although they had a similar extent of adsorption of φD-10 as did the parent strain.