Multiple oligomerisation domains in the IS911 transposase: a leucine zipper motif is essential for activity.
Structure-function relationships involved in oligomerisation of the transposase OrfAB of the bacterial insertion sequence IS911 have been investigated. Site-directed mutagenesis and sequential deletion coupled with immunoprecipitation have led to the definition of three regions of the protein capable of promoting multimerisation. These include a region predicted to assume a coiled-coil conformation, which is shown to be essential for activity, promoting correct multimerisation of the N-terminal domain of OrfAB and sequence-specific binding to the IS911 terminal inverted repeats mediated by this domain. This region presents the structural and functional characteristics of the leucine zipper motif described in eukaryotic proteins. The two other regions are located further towards the C-terminal end of the protein, adjacent to the leucine zipper and in the region that carries the conserved catalytic DD(35)E motif.
Laboratoire de Microbiologie et Génétique Moléculaire du CNRS, Université Paul Sabatier, 118 Route de Narbonne, Toulouse, 31062, France.
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L
Haren
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P
Polard
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B
Ton-Hoang
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M
Chandler
D000595:Amino Acid Sequence; D001419:Bacteria / Q000201:enzymology; D004251:DNA Transposable Elements; D016350:Leucine Zippers; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D016366:Open Reading Frames; D010957:Plasmids / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D017384:Sequence Deletion; D013329:Structure-Activity Relationship; D020079:Terminal Repeat Sequences; D019895:Transposases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
D004251:DNA Transposable Elements; D019895:Transposases