INDUCTION OF TEMPERATE CYANOPHAGES USING HEAVY METAL - COPPER

In this paper, the presence of prophages in cells of three isolates of Anabaena sp. (Anabaena sp.1, sp.2 and sp.3), Anabaena cylindrica, Nostoc muscorum and Oscillatoria sp. was investigated. Copper sulfate at concentration of 3.1x10 super( -4) M was successfully used for induction of temperate cyanophages. Among the cyanobacterial isolates tested Anabaena cylindrica was found to contain a prophage. A temperate phage was induced from Anabaena cylindrica by copper sulfate treatment and designated Ac-1. The thermal inactivation point and longevity in vitro of the induced phage isolate (Ac-1) were found to be 70 degree C and 36 hours, respectively. The induced cyanophage particles were examined by transmission electron microscopy. Ultrathin sections of infected A. cylindrica cells with temperate cyanophage and healthy ones were examined by electron microscopy. Marked changes in protoplasm and cell membrane were observed in the infected cells as compared to the healthy ones. Phage particles were detected inside the infected A. cylindrica cells.