1dc1

<StructureSection load='1dc1' size='340' side='right' caption='[[1dc1]], [[Resolution|resolution]] 1.70&Aring;' scene=''>

<table><tr><td colspan='2'>[[1dc1]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Geobacillus_stearothermophilus Geobacillus stearothermophilus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DC1 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1DC1 FirstGlance]. <br>

</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=DIO:1,4-DIETHYLENE+DIOXIDE'>DIO</scene><br>

<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Type_II_site-specific_deoxyribonuclease Type II site-specific deoxyribonuclease], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.21.4 3.1.21.4] </span></td></tr>

<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1dc1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1dc1 OCA], [http://www.rcsb.org/pdb/explore.do?structureId=1dc1 RCSB], [http://www.ebi.ac.uk/pdbsum/1dc1 PDBsum]</span></td></tr>

<table>

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== Publication Abstract from PubMed ==

BACKGROUND: Restriction endonucleases form a diverse family of proteins with substantial variation in sequence, structure, and interaction with recognition site DNA. BsoBI is a thermophilic restriction endonuclease that exhibits both base-specific and degenerate recognition within the sequence CPyCGPuG. RESULTS: The structure of BsoBI complexed to cognate DNA has been determined to 1.7 A resolution, revealing several unprecedented features. Each BsoBI monomer is formed by inserting a helical domain into an expanded EcoRI-type catalytic domain. DNA is completely encircled by a BsoBI dimer. Recognition sequence DNA lies within a 20 A long tunnel of protein that excludes bulk solvent. Interactions with the specific bases are made in both grooves through direct and water-mediated hydrogen bonding. Interaction with the degenerate position is mediated by a purine-specific hydrogen bond to N7, ensuring specificity, and water-mediated H bonding to the purine N6/O6 and pyrimidine N4/O4, allowing degeneracy. In addition to the conserved active site residues of the DX(n)(E/D)ZK restriction enzyme motif, His253 is positioned to act as a general base. CONCLUSIONS: A catalytic mechanism employing His253 and two metal ions is proposed. If confirmed, this would be the first example of histidine-mediated catalysis in a restriction endonuclease. The structure also provides two novel examples of the role of water in protein-DNA interaction. Degenerate recognition may be mediated by employing water as a hydrogen bond donor or acceptor. The structure of DNA in the tunnel may also be influenced by the absence of bulk solvent.

 

Restriction enzyme BsoBI-DNA complex: a tunnel for recognition of degenerate DNA sequences and potential histidine catalysis.,van der Woerd MJ, Pelletier JJ, Xu S, Friedman AM Structure. 2001 Feb 7;9(2):133-44. PMID:11250198<ref>PMID:11250198</ref>

 

*[[Endonuclease|Endonuclease]]

[[Category: Type II site-specific deoxyribonuclease]]

[[Category: Friedman, A M.]]

[[Category: Pelletier, J J.]]

[[Category: Woerd, M J.van der.]]

[[Category: Xu, S Y.]]

[[Category: Degenerate dna recognition]]

[[Category: Thermophilic enzyme]]