Sequence-specific chemical modification of a hybrid bacteriophage M13 single-stranded DNA by alkylating oligonucleotide derivatives.

Alkylating oligonucleotide derivatives react with the complementary sequences in hybrid M13mp7 bacteriophage single-stranded DNA and destroy the infecting ability of the DNA. The reagents do not damage M13mp9 single-stranded DNA lacking the target nucleotide sequence.