Details

Autor(en) / Beteiligte

• Schaaper, RM
• Dunn, RL

Titel

Escherichia coli mutT mutator effect during in vitro DNA synthesis. Enhanced A.G replicational errors

Ist Teil von

• The Journal of biological chemistry, 1987-12, Vol.262 (34), p.16267-16270

Ort / Verlag

Bethesda, MD: Elsevier Inc

Erscheinungsjahr

1987

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• The mechanism of the Escherichia coli mutT mutator effect was investigated using single-stranded phage as a mutational target. In vivo experiments showed that two M13mp2 lacZ alpha nonsense mutants reverted at a higher rate on a mutT1 host than on the wild-type host. The specificity of this mutator effect was identical to that observed for E. coli genes: A.T—C.G transversions. The mutT effect was subsequently demonstrated in vitro during DNA replication of M13mp2 DNA in cell-free extracts of E. coli. Replication (the single-stranded—replicative form conversion) in mutT1 extracts proceeded with a higher error rate than in wild-type extracts, and DNA sequence analysis of the in vitro revertants revealed the specific induction of A.T—C.G transversions. On the basis of the template specificity of the mutT effect in vitro, we conclude that the mutT effect involves the aberrant processing of A.G rather than T.C mispairs.