The helix–turn–helix motif of bacterial insertion sequence IS911 transposase is required for DNA binding

AUTOR(ES)

Rousseau, Philippe

FONTE

Oxford University Press

RESUMO

The transposase of IS911, a member of the IS3 family of bacterial insertion sequences, is composed of a catalytic domain located at its C-terminal end and a DNA binding domain located at its N-terminal end. Analysis of the transposases of over 60 members of the IS3 family revealed the presence of a helix–turn–helix (HTH) motif within the N-terminal region. Alignment of these potential secondary structures further revealed a completely conserved tryptophan residue similar to that found in the HTH motifs of certain homeodomain proteins. The analysis also uncovered a similarity between the IS3 family HTH and that of members of the LysR family of bacterial transcription factors. This information was used to design site-directed mutations permitting an assessment of its role in transposase function. A series of in vivo and in vitro tests demonstrated that the HTH domain is important in directing the transposase to bind the terminal inverted repeats of IS911.

Documentos Relacionados

• Conversion of a helix-turn-helix motif sequence-specific DNA binding protein into a site-specific DNA cleavage agent.
• Pogo transposase contains a putative helix-turn-helix DNA binding domain that recognises a 12 bp sequence within the terminal inverted repeats.
• Solution structure of the ETS domain from murine Ets-1: a winged helix-turn-helix DNA binding motif.
• Improved detection of helix-turn-helix DNA-binding motifs in protein sequences.
• Combinatorial Redesign of the DNA Binding Specificity of a Prokaryotic Helix-Turn-Helix Repressor