2qjg: Difference between revisions

Revision as of 19:39, 21 February 2008

M. jannaschii ADH synthase complexed with F1,6P

OverviewOverview

Genes responsible for the generation of 3-dehydroquinate (DHQ), an early metabolite in the established shikimic pathway of aromatic amino acid biosynthesis, are absent in most euryarchaeotes. Alternative gene products, Mj0400 and Mj1249, have been identified in Methanocaldococcus jannaschii as the enzymes involved in the synthesis of DHQ. 2-Amino-3,7-dideoxy-d-threo-hept-6-ulosonic acid (ADH) synthase, the product of the Mj0400 gene, catalyzes a transaldol reaction between 6-deoxy-5-ketofructose 1-phosphate and l-aspartate semialdehyde to yield ADH. Dehydroquinate synthase II, the product of the Mj1249 gene, then catalyzes deamination and cyclization of ADH, resulting in DHQ, which is fed into the canonical pathway. Three crystal structures of ADH synthase were determined in this work: a complex with a substrate analogue, fructose 1,6-bisphosphate, a complex with dihydroxyacetone phosphate (DHAP), thought to be a product of fructose 1-phosphate cleavage, and a native structure containing copurified ligands, modeled as DHAP and glycerol. On the basis of the structural analysis and comparison of the enzyme with related aldolases, ADH synthase is classified as a new member of the class I aldolase superfamily. The description of the active site allows for the identification and characterization of possible catalytic residues, Lys184, which is responsible for formation of the Schiff base intermediate, and Asp33 and Tyr153, which are candidates for the general acid/base catalysis.

About this StructureAbout this Structure

2QJG is a Single protein structure of sequence from Methanocaldococcus jannaschii with as ligand. Full crystallographic information is available from OCA.

ReferenceReference

Structure of 2-amino-3,7-dideoxy-D-threo-hept-6-ulosonic acid synthase, a catalyst in the archaeal pathway for the biosynthesis of aromatic amino acids., Morar M, White RH, Ealick SE, Biochemistry. 2007 Sep 18;46(37):10562-71. Epub 2007 Aug 22. PMID:17713928

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 ==Overview==
-Genes responsible for the generation of 3-dehydroquinate (DHQ), an early, metabolite in the established shikimic pathway of aromatic amino acid, biosynthesis, are absent in most euryarchaeotes. Alternative gene, products, Mj0400 and Mj1249, have been identified in Methanocaldococcus, jannaschii as the enzymes involved in the synthesis of DHQ., 2-Amino-3,7-dideoxy-d-threo-hept-6-ulosonic acid (ADH) synthase, the, product of the Mj0400 gene, catalyzes a transaldol reaction between, 6-deoxy-5-ketofructose 1-phosphate and l-aspartate semialdehyde to yield, ADH. Dehydroquinate synthase II, the product of the Mj1249 gene, then, catalyzes deamination and cyclization of ADH, resulting in DHQ, which is, fed into the canonical pathway. Three crystal structures of ADH synthase, were determined in this work: a complex with a substrate analogue, fructose 1,6-bisphosphate, a complex with dihydroxyacetone phosphate, (DHAP), thought to be a product of fructose 1-phosphate cleavage, and a, native structure containing copurified ligands, modeled as DHAP and, glycerol. On the basis of the structural analysis and comparison of the, enzyme with related aldolases, ADH synthase is classified as a new member, of the class I aldolase superfamily. The description of the active site, allows for the identification and characterization of possible catalytic, residues, Lys184, which is responsible for formation of the Schiff base, intermediate, and Asp33 and Tyr153, which are candidates for the general, acid/base catalysis.
+Genes responsible for the generation of 3-dehydroquinate (DHQ), an early metabolite in the established shikimic pathway of aromatic amino acid biosynthesis, are absent in most euryarchaeotes. Alternative gene products, Mj0400 and Mj1249, have been identified in Methanocaldococcus jannaschii as the enzymes involved in the synthesis of DHQ. 2-Amino-3,7-dideoxy-d-threo-hept-6-ulosonic acid (ADH) synthase, the product of the Mj0400 gene, catalyzes a transaldol reaction between 6-deoxy-5-ketofructose 1-phosphate and l-aspartate semialdehyde to yield ADH. Dehydroquinate synthase II, the product of the Mj1249 gene, then catalyzes deamination and cyclization of ADH, resulting in DHQ, which is fed into the canonical pathway. Three crystal structures of ADH synthase were determined in this work: a complex with a substrate analogue, fructose 1,6-bisphosphate, a complex with dihydroxyacetone phosphate (DHAP), thought to be a product of fructose 1-phosphate cleavage, and a native structure containing copurified ligands, modeled as DHAP and glycerol. On the basis of the structural analysis and comparison of the enzyme with related aldolases, ADH synthase is classified as a new member of the class I aldolase superfamily. The description of the active site allows for the identification and characterization of possible catalytic residues, Lys184, which is responsible for formation of the Schiff base intermediate, and Asp33 and Tyr153, which are candidates for the general acid/base catalysis.
 ==About this Structure==
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 [[Category: Methanocaldococcus jannaschii]]
 [[Category: Single protein]]
-[[Category: Ealick, S.E.]]
+[[Category: Ealick, S E.]]
 [[Category: Morar, M.]]
 [[Category: F2P]]
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 [[Category: lyase]]
-''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Jan 23 12:37:29 2008''
+''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:39:46 2008''