The activity of a temperate marine cyanophage, ms-1, of Synechococcus
sp. NKBG 042902, was induced by Cu2+. This induction was specific to C
u2+ and dependent upon Cu2+ concentration. Cr, Pb, Co, and Zn were not
effective as inducers. These results suggested that Cu2+ is a signifi
cant inducer for lysogenic cyanobacterial cells and consequently will
be a potential trigger for changes in the cyanobacterial population in
the marine environment.