1v0j
From Proteopedia
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==Overview== | ==Overview== | ||
| - | Uridine diphosphogalactofuranose (UDP-Galf) is the precursor of the | + | Uridine diphosphogalactofuranose (UDP-Galf) is the precursor of the d-galactofuranose sugar found in bacterial and parasitic cell walls, including those of many pathogens. UDP-Galf is made from UDP-galactopyranose by the enzyme UDP-galactopyranose mutase. The enzyme requires the reduced FADH- co-factor for activity. The structure of the Mycobacterium tuberculosis mutase with FAD has been determined to 2.25 A. The structures of Klebsiella pneumoniae mutase with FAD and with FADH- bound have been determined to 2.2 A and 2.35 A resolution, respectively. This is the first report of the FADH(-)-containing structure. Two flavin-dependent mechanisms for the enzyme have been proposed, one, which involves a covalent adduct being formed at the flavin and the other based on electron transfer. Using our structural data, we have examined the two mechanisms. The electron transfer mechanism is consistent with the structural data, not surprisingly, since it makes fewer demands on the precise positioning of atoms. A model based on a covalent adduct FAD requires repositioning of the enzyme active site and would appear to require the isoalloxazine ring of FADH- to buckle in a particular way. However, the FADH- structure reveals that the isoalloxazine ring buckles in the opposite sense, this apparently requires the covalent adduct to trigger profound conformational changes in the protein or to buckle the FADH- opposite to that seen in the apo structure. |
==About this Structure== | ==About this Structure== | ||
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[[Category: UDP-galactopyranose mutase]] | [[Category: UDP-galactopyranose mutase]] | ||
[[Category: Beis, K.]] | [[Category: Beis, K.]] | ||
| - | [[Category: Naismith, J | + | [[Category: Naismith, J H.]] |
[[Category: BCN]] | [[Category: BCN]] | ||
[[Category: FAD]] | [[Category: FAD]] | ||
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[[Category: mutase]] | [[Category: mutase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:30:17 2008'' |
Revision as of 13:30, 21 February 2008
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UDP-GALACTOPYRANOSE MUTASE FROM MYCOBACTERIUM TUBERCULOSIS
Overview
Uridine diphosphogalactofuranose (UDP-Galf) is the precursor of the d-galactofuranose sugar found in bacterial and parasitic cell walls, including those of many pathogens. UDP-Galf is made from UDP-galactopyranose by the enzyme UDP-galactopyranose mutase. The enzyme requires the reduced FADH- co-factor for activity. The structure of the Mycobacterium tuberculosis mutase with FAD has been determined to 2.25 A. The structures of Klebsiella pneumoniae mutase with FAD and with FADH- bound have been determined to 2.2 A and 2.35 A resolution, respectively. This is the first report of the FADH(-)-containing structure. Two flavin-dependent mechanisms for the enzyme have been proposed, one, which involves a covalent adduct being formed at the flavin and the other based on electron transfer. Using our structural data, we have examined the two mechanisms. The electron transfer mechanism is consistent with the structural data, not surprisingly, since it makes fewer demands on the precise positioning of atoms. A model based on a covalent adduct FAD requires repositioning of the enzyme active site and would appear to require the isoalloxazine ring of FADH- to buckle in a particular way. However, the FADH- structure reveals that the isoalloxazine ring buckles in the opposite sense, this apparently requires the covalent adduct to trigger profound conformational changes in the protein or to buckle the FADH- opposite to that seen in the apo structure.
About this Structure
1V0J is a Single protein structure of sequence from Mycobacterium tuberculosis with and as ligands. Active as UDP-galactopyranose mutase, with EC number 5.4.99.9 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Crystal structures of Mycobacteria tuberculosis and Klebsiella pneumoniae UDP-galactopyranose mutase in the oxidised state and Klebsiella pneumoniae UDP-galactopyranose mutase in the (active) reduced state., Beis K, Srikannathasan V, Liu H, Fullerton SW, Bamford VA, Sanders DA, Whitfield C, McNeil MR, Naismith JH, J Mol Biol. 2005 May 13;348(4):971-82. PMID:15843027
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