Transposition effect of adenine (Dam) methylation on activity of O end mutants of IS50.
The two ends of insertion sequence IS50 (from Tn5) differ in sequence and in activity during transposition: the IS50 I end contains DNA adenine methylation (Dam) sites and is affected directly by Dam methylation, whereas the O end lacks Dam sites. The effect of Dam methylation on the transposition of IS50-derived elements with base substitution mutations in their O ends was assayed to understand better how the divergent O and I ends interact. Of 31 O end mutations tested, ten impaired transposition less, and two impaired transposition more in Dam- than in Dam+ cells. These results suggest that the interaction between the two ends in a transposition complex is affected by the sequence or the extent of methylation of one end.
Tomcsanyi
T
T
Department of Microbiology and Immunology, Washington University Medical School, St Louis, MO 63110.
Berg
D E
DE
D000225:Adenine / Q000378:metabolism*; D001483:Base Sequence; D004251:DNA Transposable Elements; D008745:Methylation; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation
D004251:DNA Transposable Elements; D000225:Adenine