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| - | {{Large structure}}
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| | ==Complex of Mycobacterium smegmatis trehalose synthase with maltokinase== | | ==Complex of Mycobacterium smegmatis trehalose synthase with maltokinase== |
| - | <StructureSection load='5jy7' size='340' side='right' caption='[[5jy7]], [[Resolution|resolution]] 3.60Å' scene=''> | + | <StructureSection load='5jy7' size='340' side='right'caption='[[5jy7]], [[Resolution|resolution]] 3.60Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[5jy7]] is a 16 chain structure. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5JY7 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=5JY7 FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[5jy7]] is a 16 chain structure with sequence from [https://en.wikipedia.org/wiki/Mycolicibacterium_smegmatis_MC2_155 Mycolicibacterium smegmatis MC2 155]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=5JY7 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=5JY7 FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</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]] 3.6Å</td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Maltokinase Maltokinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.1.175 2.7.1.175] </span></td></tr> | + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=CA:CALCIUM+ION'>CA</scene></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=5jy7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5jy7 OCA], [http://pdbe.org/5jy7 PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=5jy7 RCSB], [http://www.ebi.ac.uk/pdbsum/5jy7 PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=5jy7 ProSAT]</span></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=5jy7 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=5jy7 OCA], [https://pdbe.org/5jy7 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=5jy7 RCSB], [https://www.ebi.ac.uk/pdbsum/5jy7 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=5jy7 ProSAT]</span></td></tr> |
| | </table> | | </table> |
| - | {{Large structure}} | |
| | == Function == | | == Function == |
| - | [[http://www.uniprot.org/uniprot/TRES_MYCS2 TRES_MYCS2]] Catalyzes the reversible interconversion of maltose and trehalose by transglucosylation. Maltose is the preferred substrate. To a lesser extent, also displays amylase activity, catalyzing the endohydrolysis of (1->4)-alpha-D-glucosidic linkages in glycogen and maltooligosaccharides such as maltoheptaose, to produce maltose which then can be converted to trehalose. TreS plays a key role in the utilization of trehalose for the production of glycogen, and might also function as a sensor and/or regulator of trehalose levels within the cell. Thus, when trehalose levels in the cell become dangerously low, TreS can expedite the conversion of glycogen to maltose via its amylase activity and then convert the maltose to trehalose; but this enzyme also can expedite or promote the conversion of trehalose to glycogen when cytoplasmic trehalose levels become too high. Is also able to catalyze the hydrolytic cleavage of alpha-aryl glucosides, as well as alpha-glucosyl fluoride in vitro.<ref>PMID:15511231</ref> <ref>PMID:18505459</ref> <ref>PMID:20118231</ref> <ref>PMID:21840994</ref> [[http://www.uniprot.org/uniprot/MAK_MYCS2 MAK_MYCS2]] Catalyzes the ATP-dependent phosphorylation of maltose to maltose 1-phosphate (Probable). Is involved in a branched alpha-glucan biosynthetic pathway from trehalose, together with TreS, GlgE and GlgB.<ref>PMID:20305657</ref> | + | [https://www.uniprot.org/uniprot/TRES_MYCS2 TRES_MYCS2] Catalyzes the reversible interconversion of maltose and trehalose by transglucosylation. Maltose is the preferred substrate. To a lesser extent, also displays amylase activity, catalyzing the endohydrolysis of (1->4)-alpha-D-glucosidic linkages in glycogen and maltooligosaccharides such as maltoheptaose, to produce maltose which then can be converted to trehalose. TreS plays a key role in the utilization of trehalose for the production of glycogen, and might also function as a sensor and/or regulator of trehalose levels within the cell. Thus, when trehalose levels in the cell become dangerously low, TreS can expedite the conversion of glycogen to maltose via its amylase activity and then convert the maltose to trehalose; but this enzyme also can expedite or promote the conversion of trehalose to glycogen when cytoplasmic trehalose levels become too high. Is also able to catalyze the hydrolytic cleavage of alpha-aryl glucosides, as well as alpha-glucosyl fluoride in vitro.<ref>PMID:15511231</ref> <ref>PMID:18505459</ref> <ref>PMID:20118231</ref> <ref>PMID:21840994</ref> |
| | + | <div style="background-color:#fffaf0;"> |
| | + | == Publication Abstract from PubMed == |
| | + | A growing body of evidence implicates the mycobacterial capsule - the outermost layer of the mycobacterial cell envelope - in modulation of the host immune response and virulence of mycobacteria. Mycobacteria synthesize the dominant capsule component, alpha(1-->4)-linked glucan, via three interconnected, and potentially redundant metabolic pathways. Here, we report the crystal structure of the Mycobacterium smegmatis TreS-Pep2 complex, containing trehalose synthase (TreS) and maltokinase (Pep2), which convert trehalose to maltose-1-phosphate as part of the TreS-Pep2-GlgE pathway. The structure, at 3.6 A resolution, revealed that a diamond-shaped TreS tetramer forms the core of the complex, and that pairs of Pep2 monomers bind to opposite apices of the tetramer in a 4+4 configuration. However, for the M. smegmatis orthologues, results from isothermal titration calorimetry and analytical ultracentrifugation experiments indicated that the prevalent stoichiometry in solution is 4 TreS + 2 Pep2 protomers. The observed discrepancy between the crystallised complex and the behaviour in the solution state may be explained by the relatively weak affinity of Pep2 for TreS (Kd 3.5 muM at mildly acidic pH) and crystal packing favouring the 4+4 complex. Proximity of the ATP binding site in Pep2 to the complex interface provides a rational basis for rate enhancement of Pep2 upon binding to TreS, but the complex structure appears to rule out substrate channeling between the active sites of TreS and Pep2. Our findings provide a structural model for the trehalose synthase-maltokinase complex in M. smegmatis that offers critical insights into capsule assembly. |
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| | + | Crystal structure of the TreS-Pep2 complex, initiating alpha-glucan synthesis in the GlgE pathway of mycobacteria.,Kermani AA, Roy R, Gopalasingam C, Kocurek KI, Patel TR, Alderwick LJ, Besra GS, Futterer K J Biol Chem. 2019 Mar 15. pii: RA118.004297. doi: 10.1074/jbc.RA118.004297. PMID:30877199<ref>PMID:30877199</ref> |
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| | + | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> |
| | + | </div> |
| | + | <div class="pdbe-citations 5jy7" style="background-color:#fffaf0;"></div> |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Maltokinase]] | + | [[Category: Large Structures]] |
| - | [[Category: Besra, G S]] | + | [[Category: Mycolicibacterium smegmatis MC2 155]] |
| - | [[Category: Futterer, K]] | + | [[Category: Besra GS]] |
| - | [[Category: Kermani, A A]] | + | [[Category: Futterer K]] |
| - | [[Category: Alpha glucan synthesis]] | + | [[Category: Kermani AA]] |
| - | [[Category: Complex]]
| + | |
| - | [[Category: Isomerase]]
| + | |
| - | [[Category: Isomerase-transferase complex]]
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| - | [[Category: Kinase]]
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| Structural highlights
Function
TRES_MYCS2 Catalyzes the reversible interconversion of maltose and trehalose by transglucosylation. Maltose is the preferred substrate. To a lesser extent, also displays amylase activity, catalyzing the endohydrolysis of (1->4)-alpha-D-glucosidic linkages in glycogen and maltooligosaccharides such as maltoheptaose, to produce maltose which then can be converted to trehalose. TreS plays a key role in the utilization of trehalose for the production of glycogen, and might also function as a sensor and/or regulator of trehalose levels within the cell. Thus, when trehalose levels in the cell become dangerously low, TreS can expedite the conversion of glycogen to maltose via its amylase activity and then convert the maltose to trehalose; but this enzyme also can expedite or promote the conversion of trehalose to glycogen when cytoplasmic trehalose levels become too high. Is also able to catalyze the hydrolytic cleavage of alpha-aryl glucosides, as well as alpha-glucosyl fluoride in vitro.[1] [2] [3] [4]
Publication Abstract from PubMed
A growing body of evidence implicates the mycobacterial capsule - the outermost layer of the mycobacterial cell envelope - in modulation of the host immune response and virulence of mycobacteria. Mycobacteria synthesize the dominant capsule component, alpha(1-->4)-linked glucan, via three interconnected, and potentially redundant metabolic pathways. Here, we report the crystal structure of the Mycobacterium smegmatis TreS-Pep2 complex, containing trehalose synthase (TreS) and maltokinase (Pep2), which convert trehalose to maltose-1-phosphate as part of the TreS-Pep2-GlgE pathway. The structure, at 3.6 A resolution, revealed that a diamond-shaped TreS tetramer forms the core of the complex, and that pairs of Pep2 monomers bind to opposite apices of the tetramer in a 4+4 configuration. However, for the M. smegmatis orthologues, results from isothermal titration calorimetry and analytical ultracentrifugation experiments indicated that the prevalent stoichiometry in solution is 4 TreS + 2 Pep2 protomers. The observed discrepancy between the crystallised complex and the behaviour in the solution state may be explained by the relatively weak affinity of Pep2 for TreS (Kd 3.5 muM at mildly acidic pH) and crystal packing favouring the 4+4 complex. Proximity of the ATP binding site in Pep2 to the complex interface provides a rational basis for rate enhancement of Pep2 upon binding to TreS, but the complex structure appears to rule out substrate channeling between the active sites of TreS and Pep2. Our findings provide a structural model for the trehalose synthase-maltokinase complex in M. smegmatis that offers critical insights into capsule assembly.
Crystal structure of the TreS-Pep2 complex, initiating alpha-glucan synthesis in the GlgE pathway of mycobacteria.,Kermani AA, Roy R, Gopalasingam C, Kocurek KI, Patel TR, Alderwick LJ, Besra GS, Futterer K J Biol Chem. 2019 Mar 15. pii: RA118.004297. doi: 10.1074/jbc.RA118.004297. PMID:30877199[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Pan YT, Koroth Edavana V, Jourdian WJ, Edmondson R, Carroll JD, Pastuszak I, Elbein AD. Trehalose synthase of Mycobacterium smegmatis: purification, cloning, expression, and properties of the enzyme. Eur J Biochem. 2004 Nov;271(21):4259-69. PMID:15511231 doi:10.1111/j.1432-1033.2004.04365.x
- ↑ Pan YT, Carroll JD, Asano N, Pastuszak I, Edavana VK, Elbein AD. Trehalose synthase converts glycogen to trehalose. FEBS J. 2008 Jul;275(13):3408-20. doi: 10.1111/j.1742-4658.2008.06491.x. Epub, 2008 May 23. PMID:18505459 doi:10.1111/j.1742-4658.2008.06491.x
- ↑ Elbein AD, Pastuszak I, Tackett AJ, Wilson T, Pan YT. The last step in the conversion of trehalose to glycogen:A mycobacterial enzyme that transfers maltose from maltose-1-phosphate to glycogen. J Biol Chem. 2010 Jan 29. PMID:20118231 doi:M109.033944
- ↑ Zhang R, Pan YT, He S, Lam M, Brayer GD, Elbein AD, Withers SG. Mechanistic analysis of trehalose synthase from Mycobacterium smegmatis. J Biol Chem. 2011 Oct 14;286(41):35601-9. doi: 10.1074/jbc.M111.280362. Epub 2011, Aug 12. PMID:21840994 doi:10.1074/jbc.M111.280362
- ↑ Kermani AA, Roy R, Gopalasingam C, Kocurek KI, Patel TR, Alderwick LJ, Besra GS, Futterer K. Crystal structure of the TreS-Pep2 complex, initiating alpha-glucan synthesis in the GlgE pathway of mycobacteria. J Biol Chem. 2019 Mar 15. pii: RA118.004297. doi: 10.1074/jbc.RA118.004297. PMID:30877199 doi:http://dx.doi.org/10.1074/jbc.RA118.004297
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