View source for 6ghc


==Modification dependent EcoKMcrA restriction endonuclease==
<StructureSection load='6ghc' size='340' side='right' caption='[[6ghc]], [[Resolution|resolution]] 2.85&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6ghc]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Ecoli Ecoli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6GHC OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6GHC FirstGlance]. <br>
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">mcrA, rglA, b1159, JW1145 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=83333 ECOLI])</td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=6ghc FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6ghc OCA], [http://pdbe.org/6ghc PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=6ghc RCSB], [http://www.ebi.ac.uk/pdbsum/6ghc PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=6ghc ProSAT]</span></td></tr>
</table>
== Function ==
[[http://www.uniprot.org/uniprot/MCRA_ECOLI MCRA_ECOLI]] Restriction of 5-methyl and 5-hydroxymethylcytosines at the specific DNA sequence C(me)CGG. 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Escherichia coli McrA (EcoKMcrA) acts as a methylcytosine and hydroxymethylcytosine dependent restriction endonuclease. We present a biochemical characterization of EcoKMcrA that includes the first demonstration of its endonuclease activity, small angle X-ray scattering (SAXS) data, and a crystal structure of the enzyme in the absence of DNA. Our data indicate that EcoKMcrA dimerizes via the anticipated C-terminal HNH domains, which together form a single DNA binding site. The N-terminal domains are not homologous to SRA domains, do not interact with each other, and have separate DNA binding sites. Electrophoretic mobility shift assay (EMSA) and footprinting experiments suggest that the N-terminal domains can sense the presence and sequence context of modified cytosines. Pyrrolocytosine fluorescence data indicate no base flipping. In vitro, EcoKMcrA DNA endonuclease activity requires Mn2+ ions, is not strictly methyl dependent, and is not observed when active site variants of the enzyme are used. In cells, EcoKMcrA specifically restricts DNA that is modified in the correct sequence context. This activity is impaired by mutations of the nuclease active site, unless the enzyme is highly overexpressed.

Activity and structure of EcoKMcrA.,Czapinska H, Kowalska M, Zagorskaite E, Manakova E, Slyvka A, Xu SY, Siksnys V, Sasnauskas G, Bochtler M Nucleic Acids Res. 2018 Aug 10. pii: 5068907. doi: 10.1093/nar/gky731. PMID:30107581<ref>PMID:30107581</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6ghc" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Ecoli]]
[[Category: Bochtler, M]]
[[Category: Czapinska, H]]
[[Category: Kowalska, M]]
[[Category: Manakova, E]]
[[Category: Sasnauskas, G]]
[[Category: Siksnys, V]]
[[Category: Xu, S]]
[[Category: Zagorskaite, E]]
[[Category: 5-hydroxymethylcytosine]]
[[Category: 5-methylcytosine]]
[[Category: Bba-me nuclease]]
[[Category: Hnh endonuclease]]
[[Category: Hydrolase]]
[[Category: Modification dependent restriction]]
[[Category: Scomcra]]