Abstract
The inactivating effect of hydroxylamine on Escherichia coli phages differing in the composition, structure and type of their nucleic acid was followed. It was found that the structure of the appropriate nucleic acid was an important factor affecting the sensitivity of the phages to hydroxylamine. The phages with single-stranded DNA (ϕX174) and RNA (f2, fr) were highly sensitive to hy droxylamine, whereas those with double-stranded DNA (phages of T series and phage λcb2) were substantially resistant. Lethal damage of the phage induced by hydroxylamine is partially reparable by u.v. reactivation not only at the phage λcb2 but also at the phage ϕX174. This indicates that the changes induced by hydroxylamine are partially reversible even in the phages with single-stranded nucleic acid.