4x24: Difference between revisions
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<StructureSection load='4x24' size='340' side='right'caption='[[4x24]], [[Resolution|resolution]] 1.50Å' scene=''> | <StructureSection load='4x24' size='340' side='right'caption='[[4x24]], [[Resolution|resolution]] 1.50Å' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[4x24]] is a 2 chain structure with sequence from [ | <table><tr><td colspan='2'>[[4x24]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Vibrio_cholerae_O395 Vibrio cholerae O395]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4X24 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4X24 FirstGlance]. <br> | ||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=PGE:TRIETHYLENE+GLYCOL'>PGE</scene>, <scene name='pdbligand=TDI:(3R,4S)-1-[(4-AMINO-5H-PYRROLO[3,2-D]PYRIMIDIN-7-YL)METHYL]-4-[(METHYLSULFANYL)METHYL]PYRROLIDIN-3-OL'>TDI</scene | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=PGE:TRIETHYLENE+GLYCOL'>PGE</scene>, <scene name='pdbligand=TDI:(3R,4S)-1-[(4-AMINO-5H-PYRROLO[3,2-D]PYRIMIDIN-7-YL)METHYL]-4-[(METHYLSULFANYL)METHYL]PYRROLIDIN-3-OL'>TDI</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=4x24 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4x24 OCA], [https://pdbe.org/4x24 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4x24 RCSB], [https://www.ebi.ac.uk/pdbsum/4x24 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4x24 ProSAT]</span></td></tr> | |||
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[ | |||
</table> | </table> | ||
== Function == | == Function == | ||
[ | [https://www.uniprot.org/uniprot/MTNN_VIBC3 MTNN_VIBC3] Catalyzes the irreversible cleavage of the glycosidic bond in both 5'-methylthioadenosine (MTA) and S-adenosylhomocysteine (SAH/AdoHcy) to adenine and the corresponding thioribose, 5'-methylthioribose and S-ribosylhomocysteine, respectively. | ||
<div style="background-color:#fffaf0;"> | <div style="background-color:#fffaf0;"> | ||
== Publication Abstract from PubMed == | == Publication Abstract from PubMed == | ||
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__TOC__ | __TOC__ | ||
</StructureSection> | </StructureSection> | ||
[[Category: Large Structures]] | [[Category: Large Structures]] | ||
[[Category: | [[Category: Vibrio cholerae O395]] | ||
[[Category: Almo | [[Category: Almo SC]] | ||
[[Category: Cameron | [[Category: Cameron SA]] | ||
[[Category: Schramm | [[Category: Schramm VL]] | ||
[[Category: Thomas | [[Category: Thomas K]] | ||
Revision as of 00:07, 13 April 2023
Crystal structure of Vibrio cholerae 5'-methylthioadenosine/S-adenosyl homocysteine nucleosidase (MTAN) complexed with methylthio-DADMe-Immucillin-ACrystal structure of Vibrio cholerae 5'-methylthioadenosine/S-adenosyl homocysteine nucleosidase (MTAN) complexed with methylthio-DADMe-Immucillin-A
Structural highlights
FunctionMTNN_VIBC3 Catalyzes the irreversible cleavage of the glycosidic bond in both 5'-methylthioadenosine (MTA) and S-adenosylhomocysteine (SAH/AdoHcy) to adenine and the corresponding thioribose, 5'-methylthioribose and S-ribosylhomocysteine, respectively. Publication Abstract from PubMed5'-Methylthioadenosine/S-adenosyl-l-homocysteine nucleosidases (MTANs) catalyze the hydrolysis of 5'-methylthioadenosine to adenine and 5-methylthioribose. The amino acid sequences of the MTANs from Vibrio cholerae (VcMTAN) and Escherichia coli (EcMTAN) are 60% identical and 75% similar. Protein structure folds and kinetic properties are similar. However, binding of transition-state analogues is dominated by favorable entropy in VcMTAN and by enthalpy in EcMTAN. Catalytic sites of VcMTAN and EcMTAN in contact with reactants differ by two residues; Ala113 and Val153 in VcMTAN are Pro113 and Ile152, respectively, in EcMTAN. We mutated the VcMTAN catalytic site residues to match those of EcMTAN in anticipation of altering its properties toward EcMTAN. Inhibition of VcMTAN by transition-state analogues required filling both active sites of the homodimer. However, in the Val153Ile mutant or double mutants, transition-state analogue binding at one site caused complete inhibition. Therefore, a single amino acid, Val153, alters the catalytic site cooperativity in VcMTAN. The transition-state analogue affinity and thermodynamics in mutant VcMTAN became even more unlike those of EcMTAN, the opposite of expectations from catalytic site similarity; thus, catalytic site contacts in VcMTAN are unable to recapitulate the properties of EcMTAN. X-ray crystal structures of EcMTAN, VcMTAN, and a multiple-site mutant of VcMTAN most closely resembling EcMTAN in catalytic site contacts show no major protein conformational differences. The overall protein architectures of these closely related proteins are implicated in contributing to the catalytic site differences. Active site and remote contributions to catalysis in methylthioadenosine nucleosidases.,Thomas K, Cameron SA, Almo SC, Burgos ES, Gulab SA, Schramm VL Biochemistry. 2015 Apr 21;54(15):2520-9. doi: 10.1021/bi501487w. Epub 2015 Apr 3. PMID:25806409[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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