This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.

Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.

4r7y

From Proteopedia

(Difference between revisions)

Jump to: navigation, search

Current revision

Crystal structure of an active MCM hexamer

Structural highlights

4r7y is a 2 chain structure with sequence from Pyrococcus furiosus DSM 3638 and Saccharolobus solfataricus P2. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.7Å
Ligands:	, , ,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

Q8U3I4_PYRFU MCM_SACS2 Presumptive replicative helicase. Has ATPase and DNA helicase activities. The latter preferentially melts 5'-tailed oligonucleotides and is stimulated by the SSB protein (single-stranded DNA binding protein). The active ATPase sites in the MCM ring are formed through the interaction surfaces of two neighboring subunits such that a critical structure of a conserved arginine finger motif is provided in trans relative to the ATP-binding site of the Walker A box of the adjacent subunit. The helicase function is proposed to use a partially sequential mode of ATP hydrolysis; the complex appears to tolerate multiple catalytically inactive subunits.^[1]

Publication Abstract from PubMed

In a previous Research article (<xref>Froelich et al., 2014</xref>), we suggested an MCM helicase activation mechanism, but were limited in discussing the ATPase domain because it was absent from the crystal structure. Here we present the crystal structure of a nearly full-length MCM hexamer that is helicase-active and thus has all features essential for unwinding DNA. The structure is a chimera of Sulfolobus solfataricus N-terminal domain and Pyrococcus furiosus ATPase domain. We discuss three major findings: 1) a novel conformation for the A-subdomain that could play a role in MCM regulation; 2) interaction of a universally conserved glutamine in the N-terminal Allosteric Communication Loop with the AAA+ domain helix-2-insert (h2i); and 3) a recessed binding pocket for the MCM ssDNA-binding motif influenced by the h2i. We suggest that during helicase activation, the h2i clamps down on the leading strand to facilitate strand retention and regulate ATP hydrolysis.

Analysis of the crystal structure of an active MCM hexamer.,Miller JM, Arachea BT, Epling LB, Enemark EJ Elife. 2014 Sep 29;3. doi: 10.7554/eLife.03433. PMID:25262915^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Carpentieri F, De Felice M, De Falco M, Rossi M, Pisani FM. Physical and functional interaction between the mini-chromosome maintenance-like DNA helicase and the single-stranded DNA binding protein from the crenarchaeon Sulfolobus solfataricus. J Biol Chem. 2002 Apr 5;277(14):12118-27. Epub 2002 Jan 30. PMID:11821426 doi:10.1074/jbc.M200091200
↑ Miller JM, Arachea BT, Epling LB, Enemark EJ. Analysis of the crystal structure of an active MCM hexamer. Elife. 2014 Sep 29;3. doi: 10.7554/eLife.03433. PMID:25262915 doi:http://dx.doi.org/10.7554/eLife.03433

1 Structural highlights
2 Function
3 Publication Abstract from PubMed
4 References

Proteopedia Page Contributors and Editors (what is this?)

OCA

Retrieved from "http://52.214.119.220/wiki/index.php/4r7y"

@@ Line 4: / Line 4: @@
 == Structural highlights ==
 <table><tr><td colspan='2'>[[4r7y]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Pyrococcus_furiosus_DSM_3638 Pyrococcus furiosus DSM 3638] and [https://en.wikipedia.org/wiki/Saccharolobus_solfataricus_P2 Saccharolobus solfataricus P2]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4R7Y OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4R7Y FirstGlance]. <br>
-</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
+</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.7&#8491;</td></tr>
+<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=ADP:ADENOSINE-5-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=MG:MAGNESIUM+ION'>MG</scene>, <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene></td></tr>
 <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=4r7y FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4r7y OCA], [https://pdbe.org/4r7y PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4r7y RCSB], [https://www.ebi.ac.uk/pdbsum/4r7y PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4r7y ProSAT]</span></td></tr>
 </table>

4r7y

From Proteopedia

Current revision

Crystal structure of an active MCM hexamer

Structural highlights

Function

Publication Abstract from PubMed

References

Contents

Proteopedia Page Contributors and Editors (what is this?)

Views

Personal tools

Navigation

Search

Toolbox