2hr1: Difference between revisions
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==Ternary structure of WT M.HhaI C5-Cytosine DNA methyltransferase with unmodified DNA and AdoHcy== | ==Ternary structure of WT M.HhaI C5-Cytosine DNA methyltransferase with unmodified DNA and AdoHcy== | ||
<StructureSection load='2hr1' size='340' side='right' caption='[[2hr1]], [[Resolution|resolution]] 1.96Å' scene=''> | <StructureSection load='2hr1' size='340' side='right'caption='[[2hr1]], [[Resolution|resolution]] 1.96Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[2hr1]] is a 3 chain structure with sequence from [ | <table><tr><td colspan='2'>[[2hr1]] is a 3 chain structure with sequence from [https://en.wikipedia.org/wiki/Atcc_10014 Atcc 10014]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2HR1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2HR1 FirstGlance]. <br> | ||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=SAH:S-ADENOSYL-L-HOMOCYSTEINE'>SAH</scene></td></tr> | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=SAH:S-ADENOSYL-L-HOMOCYSTEINE'>SAH</scene></td></tr> | ||
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[3mht|3mht]]</td></tr> | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat"><div style='overflow: auto; max-height: 3em;'>[[3mht|3mht]]</div></td></tr> | ||
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">hhaIM ([ | <tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">hhaIM ([https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=735 ATCC 10014])</td></tr> | ||
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[ | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[https://en.wikipedia.org/wiki/DNA_(cytosine-5-)-methyltransferase DNA (cytosine-5-)-methyltransferase], with EC number [https://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.1.37 2.1.1.37] </span></td></tr> | ||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2hr1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2hr1 OCA], [https://pdbe.org/2hr1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2hr1 RCSB], [https://www.ebi.ac.uk/pdbsum/2hr1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2hr1 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[[ | [[https://www.uniprot.org/uniprot/MTH1_HAEPH MTH1_HAEPH]] This methylase recognizes the double-stranded sequence GCGC, causes specific methylation on C-2 on both strands, and protects the DNA from cleavage by the HhaI endonuclease. | ||
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
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==See Also== | ==See Also== | ||
*[[DNA methyltransferase|DNA methyltransferase]] | *[[DNA methyltransferase 3D structures|DNA methyltransferase 3D structures]] | ||
== References == | == References == | ||
<references/> | <references/> | ||
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</StructureSection> | </StructureSection> | ||
[[Category: Atcc 10014]] | [[Category: Atcc 10014]] | ||
[[Category: Large Structures]] | |||
[[Category: Shieh, F]] | [[Category: Shieh, F]] | ||
[[Category: High resolution]] | [[Category: High resolution]] | ||
[[Category: M hhai]] | [[Category: M hhai]] | ||
[[Category: Transferase-dna complex]] | [[Category: Transferase-dna complex]] | ||
Revision as of 10:20, 24 March 2021
Ternary structure of WT M.HhaI C5-Cytosine DNA methyltransferase with unmodified DNA and AdoHcyTernary structure of WT M.HhaI C5-Cytosine DNA methyltransferase with unmodified DNA and AdoHcy
Structural highlights
Function[MTH1_HAEPH] This methylase recognizes the double-stranded sequence GCGC, causes specific methylation on C-2 on both strands, and protects the DNA from cleavage by the HhaI endonuclease. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedArg165 forms part of a previously identified base flipping motif in the bacterial DNA cytosine methyltransferase, M.HhaI. Replacement of Arg165 with Ala has no detectable effect on either DNA or AdoMet affinity, yet causes the base flipping and restacking transitions to be decreased approximately 16 and 190-fold respectively, thus confirming the importance of this motif. However, these kinetic changes cannot account for the mutant's observed 10(5)-fold decreased catalytic rate. The mutant enzyme/cognate DNA cocrystal structure (2.79 A resolution) shows the target cytosine to be positioned approximately 30 degrees into the major groove, which is consistent with a major groove pathway for nucleotide flipping. The pyrimidine-sugar chi angle is rotated to approximately +171 degrees, from a range of -95 degrees to -120 degrees in B DNA, and -77 degrees in the WT M.HhaI complex. Thus, Arg165 is important for maintaining the cytosine positioned for nucleophilic attack by Cys81. The cytosine sugar pucker is in the C2'-endo-C3'-exo (South conformation), in contrast to the previously reported C3'-endo (North conformation) described for the original 2.70 A resolution cocrystal structure of the WT M.HhaI/DNA complex. We determined a high resolution structure of the WT M.HhaI/DNA complex (1.96 A) to better determine the sugar pucker. This new structure is similar to the original, lower resolution WT M.HhaI complex, but shows that the sugar pucker is O4'-endo (East conformation), intermediate between the South and North conformers. In summary, Arg165 plays significant roles in base flipping, cytosine positioning, and catalysis. Furthermore, the previously proposed M.HhaI-mediated changes in sugar pucker may not be an important contributor to the base flipping mechanism. These results provide insights into the base flipping and catalytic mechanisms for bacterial and eukaryotic DNA methyltransferases. The role of Arg165 towards base flipping, base stabilization and catalysis in M.HhaI.,Shieh FK, Youngblood B, Reich NO J Mol Biol. 2006 Sep 22;362(3):516-27. Epub 2006 Jul 22. PMID:16926025[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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