1bp0: Difference between revisions
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<StructureSection load='1bp0' size='340' side='right'caption='[[1bp0]], [[Resolution|resolution]] 2.40Å' scene=''> | <StructureSection load='1bp0' size='340' side='right'caption='[[1bp0]], [[Resolution|resolution]] 2.40Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[1bp0]] is a 1 chain structure with sequence from [ | <table><tr><td colspan='2'>[[1bp0]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Lacticaseibacillus_casei Lacticaseibacillus casei]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1BP0 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=1BP0 FirstGlance]. <br> | ||
</td></tr><tr id=' | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.4Å</td></tr> | ||
<tr id=' | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=UMP:2-DEOXYURIDINE+5-MONOPHOSPHATE'>UMP</scene></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=1bp0 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1bp0 OCA], [https://pdbe.org/1bp0 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=1bp0 RCSB], [https://www.ebi.ac.uk/pdbsum/1bp0 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=1bp0 ProSAT]</span></td></tr> | ||
</table> | </table> | ||
== Function == | == Function == | ||
[ | [https://www.uniprot.org/uniprot/TYSY_LACCA TYSY_LACCA] Provides the sole de novo source of dTMP for DNA biosynthesis. | ||
== Evolutionary Conservation == | == Evolutionary Conservation == | ||
[[Image:Consurf_key_small.gif|200px|right]] | [[Image:Consurf_key_small.gif|200px|right]] | ||
| Line 31: | Line 31: | ||
==See Also== | ==See Also== | ||
*[[Thymidylate synthase|Thymidylate synthase]] | *[[Thymidylate synthase 3D structures|Thymidylate synthase 3D structures]] | ||
== References == | == References == | ||
<references/> | <references/> | ||
__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
[[Category: | [[Category: Lacticaseibacillus casei]] | ||
[[Category: Large Structures]] | [[Category: Large Structures]] | ||
[[Category: Finer-Moore J]] | |||
[[Category: Finer-Moore | [[Category: Morse R]] | ||
[[Category: Morse | [[Category: Stroud RM]] | ||
[[Category: Stroud | |||
Latest revision as of 08:40, 9 August 2023
THYMIDYLATE SYNTHASE R23I MUTANTTHYMIDYLATE SYNTHASE R23I MUTANT
Structural highlights
FunctionTYSY_LACCA Provides the sole de novo source of dTMP for DNA biosynthesis. 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 PubMedIn thymidylate synthase, four conserved arginines provide two hydrogen bonds each to the oxygens of the phosphate group of the substrate, 2'-deoxyuridine-5'-monophosphate. Of these, R23, R178, and R179 are far removed from the site of methyl transfer and contribute to catalysis solely through binding and orientation of ligands. These arginines can be substituted by other residues, while still retaining more than 1% activity of the wild-type enzyme. We compared the kinetics and determined the crystal structures of dUMP complexes of three of the most active, uncharged single mutants of these arginines, R23I, R178T, and R179T, and of double mutants (R23I, R179T) and (R178T, R179T). The dramatically higher K(m) for R178T compared to the other two single mutants arises from the effects of R178 substitution on the orientation of dUMP; 10-15-fold increases in for R23I and R178T reflect the role of these residues in stabilizing the closed conformation of TS in ternary complexes. The free energy for productive dUMP binding, DeltaG(S), increases by at least 1 kcal/mol for each mutant, even when dUMP orientation and mobility in the crystal structure is the same as in wild-type enzyme. Thus, the four arginines do not contribute excess positive charge to the PO(4)(-2) binding site; rather, they ideally complement the charge and geometry of the phosphate moiety. More-than-additive increases in DeltaG(S) seen in the double mutants are consistent with quadratic increases in DeltaG(S) predicted for deviations from ideal electrostatic interactions and may also reflect cooperative binding of the arginines to the phosphate oxygens. Energetic contributions of four arginines to phosphate-binding in thymidylate synthase are more than additive and depend on optimization of "effective charge balance".,Morse RJ, Kawase S, Santi DV, Finer-Moore J, Stroud RM Biochemistry. 2000 Feb 8;39(5):1011-20. PMID:10653645[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences |
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