3k4c: Difference between revisions
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==Pyranose 2-oxidase H167A/T169G mutant== | |||
===Pyranose | <StructureSection load='3k4c' size='340' side='right' caption='[[3k4c]], [[Resolution|resolution]] 1.70Å' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[3k4c]] is a 4 chain structure with sequence from [http://en.wikipedia.org/wiki/Trametes_ochracea Trametes ochracea]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=3K4C OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=3K4C FirstGlance]. <br> | |||
</td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=1PE:PENTAETHYLENE+GLYCOL'>1PE</scene>, <scene name='pdbligand=FAD:FLAVIN-ADENINE+DINUCLEOTIDE'>FAD</scene>, <scene name='pdbligand=MES:2-(N-MORPHOLINO)-ETHANESULFONIC+ACID'>MES</scene></td></tr> | |||
<tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1tt0|1tt0]], [[2igo|2igo]], [[2igk|2igk]], [[2igm|2igm]], [[2ign|2ign]], [[3bg6|3bg6]], [[3k4b|3k4b]]</td></tr> | |||
<tr id='gene'><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">p2o ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=230624 Trametes ochracea])</td></tr> | |||
<tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Pyranose_oxidase Pyranose oxidase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.1.3.10 1.1.3.10] </span></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=3k4c FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=3k4c OCA], [http://www.rcsb.org/pdb/explore.do?structureId=3k4c RCSB], [http://www.ebi.ac.uk/pdbsum/3k4c PDBsum]</span></td></tr> | |||
</table> | |||
== Evolutionary Conservation == | |||
[[Image:Consurf_key_small.gif|200px|right]] | |||
Check<jmol> | |||
<jmolCheckbox> | |||
<scriptWhenChecked>select protein; define ~consurf_to_do selected; consurf_initial_scene = true; script "/wiki/ConSurf/k4/3k4c_consurf.spt"</scriptWhenChecked> | |||
<scriptWhenUnchecked>script /wiki/extensions/Proteopedia/spt/initialview01.spt</scriptWhenUnchecked> | |||
<text>to colour the structure by Evolutionary Conservation</text> | |||
</jmolCheckbox> | |||
</jmol>, as determined by [http://consurfdb.tau.ac.il/ ConSurfDB]. You may read the [[Conservation%2C_Evolutionary|explanation]] of the method and the full data available from [http://bental.tau.ac.il/new_ConSurfDB/chain_selection.php?pdb_ID=2ata ConSurf]. | |||
<div style="clear:both"></div> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Pyranose 2-oxidase (P2O) catalyzes the oxidation by O(2) of d-glucose and several aldopyranoses to yield the 2-ketoaldoses and H(2)O(2). Based on crystal structures, in one rotamer conformation, the threonine hydroxyl of Thr(169) forms H-bonds to the flavin-N5/O4 locus, whereas, in a different rotamer, it may interact with either sugar or other parts of the P2O.sugar complex. Transient kinetics of wild-type (WT) and Thr(169) --> S/N/G/A replacement variants show that D-Glc binds to T169S, T169N, and WT with the same K(d) (45-47 mm), and the hydride transfer rate constants (k(red)) are similar (15.3-9.7 s(-1) at 4 degrees C). k(red) of T169G with D-glucose (0.7 s(-1), 4 degrees C) is significantly less than that of WT but not as severely affected as in T169A (k(red) of 0.03 s(-1) at 25 degrees C). Transient kinetics of WT and mutants using d-galactose show that P2O binds d-galactose with a one-step binding process, different from binding of d-glucose. In T169S, T169N, and T169G, the overall turnover with d-Gal is faster than that of WT due to an increase of k(red). In the crystal structure of T169S, Ser(169) O gamma assumes a position identical to that of O gamma 1 in Thr(169); in T169G, solvent molecules may be able to rescue H-bonding. Our data suggest that a competent reductive half-reaction requires a side chain at position 169 that is able to form an H-bond within the ES complex. During the oxidative half-reaction, all mutants failed to stabilize a C4a-hydroperoxyflavin intermediate, thus suggesting that the precise position and geometry of the Thr(169) side chain are required for intermediate stabilization. | |||
A conserved active-site threonine is important for both sugar and flavin oxidations of pyranose 2-oxidase.,Pitsawong W, Sucharitakul J, Prongjit M, Tan TC, Spadiut O, Haltrich D, Divne C, Chaiyen P J Biol Chem. 2010 Mar 26;285(13):9697-705. Epub 2010 Jan 20. PMID:20089849<ref>PMID:20089849</ref> | |||
== | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
</div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Pyranose oxidase]] | [[Category: Pyranose oxidase]] | ||
[[Category: Trametes ochracea]] | [[Category: Trametes ochracea]] | ||
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[[Category: Oxidoreductase]] | [[Category: Oxidoreductase]] | ||
[[Category: Phbh fold]] | [[Category: Phbh fold]] | ||
[[Category: | [[Category: Rossmann fold]] |
Revision as of 17:22, 3 November 2014
Pyranose 2-oxidase H167A/T169G mutantPyranose 2-oxidase H167A/T169G mutant
Structural highlights
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 PubMedPyranose 2-oxidase (P2O) catalyzes the oxidation by O(2) of d-glucose and several aldopyranoses to yield the 2-ketoaldoses and H(2)O(2). Based on crystal structures, in one rotamer conformation, the threonine hydroxyl of Thr(169) forms H-bonds to the flavin-N5/O4 locus, whereas, in a different rotamer, it may interact with either sugar or other parts of the P2O.sugar complex. Transient kinetics of wild-type (WT) and Thr(169) --> S/N/G/A replacement variants show that D-Glc binds to T169S, T169N, and WT with the same K(d) (45-47 mm), and the hydride transfer rate constants (k(red)) are similar (15.3-9.7 s(-1) at 4 degrees C). k(red) of T169G with D-glucose (0.7 s(-1), 4 degrees C) is significantly less than that of WT but not as severely affected as in T169A (k(red) of 0.03 s(-1) at 25 degrees C). Transient kinetics of WT and mutants using d-galactose show that P2O binds d-galactose with a one-step binding process, different from binding of d-glucose. In T169S, T169N, and T169G, the overall turnover with d-Gal is faster than that of WT due to an increase of k(red). In the crystal structure of T169S, Ser(169) O gamma assumes a position identical to that of O gamma 1 in Thr(169); in T169G, solvent molecules may be able to rescue H-bonding. Our data suggest that a competent reductive half-reaction requires a side chain at position 169 that is able to form an H-bond within the ES complex. During the oxidative half-reaction, all mutants failed to stabilize a C4a-hydroperoxyflavin intermediate, thus suggesting that the precise position and geometry of the Thr(169) side chain are required for intermediate stabilization. A conserved active-site threonine is important for both sugar and flavin oxidations of pyranose 2-oxidase.,Pitsawong W, Sucharitakul J, Prongjit M, Tan TC, Spadiut O, Haltrich D, Divne C, Chaiyen P J Biol Chem. 2010 Mar 26;285(13):9697-705. Epub 2010 Jan 20. PMID:20089849[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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