1g1a: Difference between revisions
New page: left|200px<br /><applet load="1g1a" size="450" color="white" frame="true" align="right" spinBox="true" caption="1g1a, resolution 2.47Å" /> '''THE CRYSTAL STRUCTUR... |
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[[Image:1g1a.gif|left|200px]]<br /><applet load="1g1a" size=" | [[Image:1g1a.gif|left|200px]]<br /><applet load="1g1a" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1g1a, resolution 2.47Å" /> | caption="1g1a, resolution 2.47Å" /> | ||
'''THE CRYSTAL STRUCTURE OF DTDP-D-GLUCOSE 4,6-DEHYDRATASE (RMLB)FROM SALMONELLA ENTERICA SEROVAR TYPHIMURIUM'''<br /> | '''THE CRYSTAL STRUCTURE OF DTDP-D-GLUCOSE 4,6-DEHYDRATASE (RMLB)FROM SALMONELLA ENTERICA SEROVAR TYPHIMURIUM'''<br /> | ||
==Overview== | ==Overview== | ||
l-Rhamnose is a 6-deoxyhexose that is found in a variety of different | l-Rhamnose is a 6-deoxyhexose that is found in a variety of different glycoconjugates in the cell walls of pathogenic bacteria. The precursor of l-rhamnose is dTDP-l-rhamnose, which is synthesised from glucose- 1-phosphate and deoxythymidine triphosphate (dTTP) via a pathway requiring four enzymes. Significantly this pathway does not exist in humans and all four enzymes therefore represent potential therapeutic targets. dTDP-D-glucose 4,6-dehydratase (RmlB; EC 4.2.1.46) is the second enzyme in the dTDP-L-rhamnose biosynthetic pathway. The structure of Salmonella enterica serovar Typhimurium RmlB had been determined to 2.47 A resolution with its cofactor NAD(+) bound. The structure has been refined to a crystallographic R-factor of 20.4 % and an R-free value of 24.9 % with good stereochemistry.RmlB functions as a homodimer with monomer association occurring principally through hydrophobic interactions via a four-helix bundle. Each monomer exhibits an alpha/beta structure that can be divided into two domains. The larger N-terminal domain binds the nucleotide cofactor NAD(+) and consists of a seven-stranded beta-sheet surrounded by alpha-helices. The smaller C-terminal domain is responsible for binding the sugar substrate dTDP-d-glucose and contains four beta-strands and six alpha-helices. The two domains meet to form a cavity in the enzyme. The highly conserved active site Tyr(167)XXXLys(171) catalytic couple and the GlyXGlyXXGly motif at the N terminus characterise RmlB as a member of the short-chain dehydrogenase/reductase extended family.The quaternary structure of RmlB and its similarity to a number of other closely related short-chain dehydrogenase/reductase enzymes have enabled us to propose a mechanism of catalysis for this important enzyme. | ||
==About this Structure== | ==About this Structure== | ||
1G1A is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Salmonella_enterica Salmonella enterica] with SO4 and NAD as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/dTDP-glucose_4,6-dehydratase dTDP-glucose 4,6-dehydratase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.46 4.2.1.46] Full crystallographic information is available from [http:// | 1G1A is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Salmonella_enterica Salmonella enterica] with <scene name='pdbligand=SO4:'>SO4</scene> and <scene name='pdbligand=NAD:'>NAD</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/dTDP-glucose_4,6-dehydratase dTDP-glucose 4,6-dehydratase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.46 4.2.1.46] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1G1A OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: dTDP-glucose 4,6-dehydratase]] | [[Category: dTDP-glucose 4,6-dehydratase]] | ||
[[Category: Allard, S | [[Category: Allard, S T.M.]] | ||
[[Category: Giraud, M | [[Category: Giraud, M F.]] | ||
[[Category: Graninger, M.]] | [[Category: Graninger, M.]] | ||
[[Category: Messner, P.]] | [[Category: Messner, P.]] | ||
[[Category: Naismith, J | [[Category: Naismith, J H.]] | ||
[[Category: Whitfield, C.]] | [[Category: Whitfield, C.]] | ||
[[Category: NAD]] | [[Category: NAD]] | ||
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[[Category: short chain dehydrogenase]] | [[Category: short chain dehydrogenase]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:44:57 2008'' | ||
Revision as of 13:44, 21 February 2008
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THE CRYSTAL STRUCTURE OF DTDP-D-GLUCOSE 4,6-DEHYDRATASE (RMLB)FROM SALMONELLA ENTERICA SEROVAR TYPHIMURIUM
OverviewOverview
l-Rhamnose is a 6-deoxyhexose that is found in a variety of different glycoconjugates in the cell walls of pathogenic bacteria. The precursor of l-rhamnose is dTDP-l-rhamnose, which is synthesised from glucose- 1-phosphate and deoxythymidine triphosphate (dTTP) via a pathway requiring four enzymes. Significantly this pathway does not exist in humans and all four enzymes therefore represent potential therapeutic targets. dTDP-D-glucose 4,6-dehydratase (RmlB; EC 4.2.1.46) is the second enzyme in the dTDP-L-rhamnose biosynthetic pathway. The structure of Salmonella enterica serovar Typhimurium RmlB had been determined to 2.47 A resolution with its cofactor NAD(+) bound. The structure has been refined to a crystallographic R-factor of 20.4 % and an R-free value of 24.9 % with good stereochemistry.RmlB functions as a homodimer with monomer association occurring principally through hydrophobic interactions via a four-helix bundle. Each monomer exhibits an alpha/beta structure that can be divided into two domains. The larger N-terminal domain binds the nucleotide cofactor NAD(+) and consists of a seven-stranded beta-sheet surrounded by alpha-helices. The smaller C-terminal domain is responsible for binding the sugar substrate dTDP-d-glucose and contains four beta-strands and six alpha-helices. The two domains meet to form a cavity in the enzyme. The highly conserved active site Tyr(167)XXXLys(171) catalytic couple and the GlyXGlyXXGly motif at the N terminus characterise RmlB as a member of the short-chain dehydrogenase/reductase extended family.The quaternary structure of RmlB and its similarity to a number of other closely related short-chain dehydrogenase/reductase enzymes have enabled us to propose a mechanism of catalysis for this important enzyme.
About this StructureAbout this Structure
1G1A is a Single protein structure of sequence from Salmonella enterica with and as ligands. Active as dTDP-glucose 4,6-dehydratase, with EC number 4.2.1.46 Full crystallographic information is available from OCA.
ReferenceReference
The crystal structure of dTDP-D-Glucose 4,6-dehydratase (RmlB) from Salmonella enterica serovar Typhimurium, the second enzyme in the dTDP-l-rhamnose pathway., Allard ST, Giraud MF, Whitfield C, Graninger M, Messner P, Naismith JH, J Mol Biol. 2001 Mar 16;307(1):283-95. PMID:11243820
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