A Bacterial Virus for Actinomyces griseus

Abstract

An actinophage was observed in laboratory cultures of A. griseus which were exposed to the air. Filtrates of this culture prevented growth of A. griseus, and on agar medium showed the typical "moth-eaten" appearance of bacteriophages. The original filtrate contained 55,000,000 plaque-forming units per ml. Resistant strains of A. griseus were developed, which may be lysogenic. Electron microscope observations show the particulate nature of this bacteriophage, and its close resemblance to strains of Escherichia coli phase.