2A6O

Crystal Structure of the ISHp608 Transposase in Complex with Stem-loop DNA

Summary for 2A6O

• Entry DOI: 10.2210/pdb2a6o/pdb
• Related: 2A6M
• Descriptor: 5'-D(*CP*CP*CP*CP*TP*AP*GP*CP*TP*TP*TP*AP*GP*CP*TP*AP*TP*GP*GP*GP*GP*A)-3', ISHp608 Transposase (3 entities in total)
• Functional Keywords: rna recognition motif, dna stem-loop, transcription-dna complex, transcription/dna
• Biological source: Helicobacter pylori
• Total number of polymer chains: 4
• Total formula weight: 49699.00

Authors

Ronning, D.R.,Guynet, C.,Ton-Hoang, B.,Perez, Z.N.,Ghirlando, R.,Chandler, M.,Dyda, F. (deposition date: 2005-07-03, release date: 2005-10-25, Last modification date: 2023-08-23)

Primary citation

Ronning, D.R.,Guynet, C.,Ton-Hoang, B.,Perez, Z.N.,Ghirlando, R.,Chandler, M.,Dyda, F.
Active site sharing and subterminal hairpin recognition in a new class of DNA transposases.
Mol.Cell, 20:143-154, 2005

PubMed Abstract: Many bacteria harbor simple transposable elements termed insertion sequences (IS). In Helicobacter pylori, the chimeric IS605 family elements are particularly interesting due to their proximity to genes encoding gastric epithelial invasion factors. Protein sequences of IS605 transposases do not bear the hallmarks of other well-characterized transposases. We have solved the crystal structure of full-length transposase (TnpA) of a representative member, ISHp608. Structurally, TnpA does not resemble any characterized transposase; rather, it is related to rolling circle replication (RCR) proteins. Consistent with RCR, Mg2+ and a conserved tyrosine, Tyr127, are essential for DNA nicking and the formation of a covalent intermediate between TnpA and DNA. TnpA is dimeric, contains two shared active sites, and binds two DNA stem loops representing the conserved inverted repeats near each end of ISHp608. The cocrystal structure with stem-loop DNA illustrates how this family of transposases specifically recognizes and pairs ends, necessary steps during transposition.

PubMed: 16209952
DOI: 10.1016/j.molcel.2005.07.026

Experimental method

X-RAY DIFFRACTION (2.6 Å)