CRYSTAL STRUCTURE OF E. COLI SEQA COMPLEXED WITH HEMIMETHYLATED DNACRYSTAL STRUCTURE OF E. COLI SEQA COMPLEXED WITH HEMIMETHYLATED DNA
Structural highlights
1lrr is a 6 chain structure with sequence from Escherichia coli. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
SEQA_ECOLI Negative regulator of replication initiation, which contributes to regulation of DNA replication and ensures that replication initiation occurs exactly once per chromosome per cell cycle. Binds to pairs of hemimethylated GATC sequences in the oriC region, thus preventing assembly of replication proteins and re-initiation at newly replicated origins. Repression is relieved when the region becomes fully methylated. Can also bind to hemimethylated GATC sequences outside of oriC region. Binds, with less affinity, to fully methylated GATC sites and affects timing of replication. May play a role in chromosome organization and gene regulation.[1][2][3][4][5][6]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
References
↑Lu M, Campbell JL, Boye E, Kleckner N. SeqA: a negative modulator of replication initiation in E. coli. Cell. 1994 May 6;77(3):413-26. PMID:8011018
↑von Freiesleben U, Rasmussen KV, Schaechter M. SeqA limits DnaA activity in replication from oriC in Escherichia coli. Mol Microbiol. 1994 Nov;14(4):763-72. PMID:7891562
↑Slater S, Wold S, Lu M, Boye E, Skarstad K, Kleckner N. E. coli SeqA protein binds oriC in two different methyl-modulated reactions appropriate to its roles in DNA replication initiation and origin sequestration. Cell. 1995 Sep 22;82(6):927-36. PMID:7553853
↑Brendler T, Sawitzke J, Sergueev K, Austin S. A case for sliding SeqA tracts at anchored replication forks during Escherichia coli chromosome replication and segregation. EMBO J. 2000 Nov 15;19(22):6249-58. PMID:11080170 doi:10.1093/emboj/19.22.6249
↑Skarstad K, Lueder G, Lurz R, Speck C, Messer W. The Escherichia coli SeqA protein binds specifically and co-operatively to two sites in hemimethylated and fully methylated oriC. Mol Microbiol. 2000 Jun;36(6):1319-26. PMID:10931282
↑Sanchez-Romero MA, Busby SJ, Dyer NP, Ott S, Millard AD, Grainger DC. Dynamic distribution of seqa protein across the chromosome of escherichia coli K-12. MBio. 2010 May 18;1(1). pii: e00012-10. doi: 10.1128/mBio.00012-10. PMID:20689753 doi:10.1128/mBio.00012-10
