THE PROPERTIES OF X-RAY INACTIVATED BACTERIOPHAGE II

Abstract

The inactivation of bacteriophages of the T group by X-rays was investigated under conditions where indirect effects are prevalent, and the properties of the inactive viruses were studied. Indirect inactivation is caused by at least 2 agents or groups of agents. One, short-lived, is detectable only by its action during actual exposure of phage to radiation; the other, relatively stable, is detected by the persistence of its effect after irradiation. Many factors in the composition of the medium influence the amt. of inactivation. Phages of the T2 group, inactivated by the short-lived, indirect agent, exhibit a reduced ability to be adsorbed by bacteria; the active survivors are also adsorbed slowly. The same phages, inactivated by the stable indirect agent, show an adsorption ability only slightly reduced, and many of the inactive particles that are adsorbed are still able to kill the host bacteria and to be reactivated in multiple infected bacteria. No photoreactivation has been observed. All types of inactive phage particles produced by indirect effects of X-rays differ in their properties from phage inactivated by the direct effect of X-rays or by u.-v. light.