Role for deoxyribonucleic acid ligase in deoxyribonucleic acid polymerase i-dependent repair synthesis in toluene-treated escherichia coli.

In a toluene-treated mutant of Escherichia coli K-12 having a temperature-sensitive, conditionally lethal mutation in the structural gene for deoxyribonucleic acid (DNA) ligase, an extensive DNA repair synthesis occurred in X-irradiated cells at the nonpermissive temperature, 42 C. At the permissive temperature, 30 C, nearly normal semiconservative synthesis and limited repair synthesis were observed when DNA ligase was activated by the addition of nicotinamide adenine dinucleotide.