2ve9
From Proteopedia
Xray structure of KOPS bound gamma domain of FtsK (P. aeruginosa)
Structural highlights
FunctionFTSK_PSEAE Essential cell division protein that coordinates cell division and chromosome segregation. The N-terminus is involved in assembly of the cell-division machinery. The C-terminus functions as a DNA motor that moves dsDNA in an ATP-dependent manner towards the dif recombination site, which is located within the replication terminus region. Translocation stops specifically at Xer-dif sites, where FtsK interacts with the Xer recombinase, allowing activation of chromosome unlinking by recombination. FtsK orienting polar sequences (KOPS) guide the direction of DNA translocation. FtsK can remove proteins from DNA as it translocates, but translocation stops specifically at XerCD-dif site, thereby preventing removal of XerC and XerD from dif (Probable).[1] [2] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedDimeric circular chromosomes, formed by recombination between monomer sisters, cannot be segregated to daughter cells at cell division. XerCD site-specific recombination at the Escherichia coli dif site converts these dimers to monomers in a reaction that requires the DNA translocase FtsK. Short DNA sequences, KOPS (GGGNAGGG), which are polarized toward dif in the chromosome, direct FtsK translocation. FtsK interacts with KOPS through a C-terminal winged helix domain gamma. The crystal structure of three FtsKgamma domains bound to 8 bp KOPS DNA demonstrates how three gamma domains recognize KOPS. Using covalently linked dimers of FtsK, we infer that three gamma domains per hexamer are sufficient to recognize KOPS and load FtsK and subsequently activate recombination at dif. During translocation, FtsK fails to recognize an inverted KOPS sequence. Therefore, we propose that KOPS act solely as a loading site for FtsK, resulting in a unidirectionally oriented hexameric motor upon DNA. Molecular mechanism of sequence-directed DNA loading and translocation by FtsK.,Lowe J, Ellonen A, Allen MD, Atkinson C, Sherratt DJ, Grainge I Mol Cell. 2008 Aug 22;31(4):498-509. PMID:18722176[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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