Phage-inactivating Effect of Iron(II)-Ascorbate Complex

The effect of iron(II)-ascorbate complex on various phages was investigated. At 10- (6) M, the complex inactivated all nine phages examined. The mechanism of the inactivation was studied with phage J1, the most sensitive to the complex. The addition of H2O2 or Cu(2+) to the reaction mixture increased the inactivation. Bubbling of nitrogen through the reaction mixture and the addition of Fe(3+), a reducing agent, a chelating agent, or a radical scavenger prevented inactivation. These findings suggest the involvement of oxygen radicals in the inactivation. The complex had no effects on the SDS-PAGE pattern or amino acid composition of bovine serum albumin, or the structural protein of phage J1. The complex nicked the supercoiled form of pUC18 DNA, giving first single-stranded breaks (the open circular form) and then double-stranded breaks (the linear form). Strands of M13mp8 DNA, λDNA, and J1 DNA were also broken. The breaks could account for the inactivation.