PDBsum entry 2qjh

Lyase

PDB id: 2qjh

Contents

Protein chains

(+ 14 more) 264 a.a. *

Ligands

13P ×20

Waters ×413

* Residue conservation analysis

PDB id:

2qjh

Name:

Lyase

Title:

M. Jannaschii adh synthase covalently bound to dihydroxyacetone phosphate

Structure:

Putative aldolase mj0400. Chain: a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t. Engineered: yes

Source:

Methanocaldococcus jannaschii. Organism_taxid: 2190. Expressed in: escherichia coli. Expression_system_taxid: 562

Resolution:

2.60Å R-factor: 0.203 R-free: 0.244

Authors:

S.E.Ealick,M.Morar

Key ref:

M.Morar et al. (2007). 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. Biochemistry, 46, 10562-10571. PubMed id: 17713928

Date:

07-Jul-07 Release date: 30-Oct-07

Protein chains

Q57843  (ADHS_METJA) -  2-amino-3,7-dideoxy-D-threo-hept-6-ulosonate synthase from Methanocaldococcus jannaschii (strain ATCC 43067 / DSM 2661 / JAL-1 / JCM 10045 / NBRC 100440)

Seq: 273 a.a.

Struc: 264 a.a.

Enzyme reactions

• Enzyme class: E.C.2.2.1.10 - 2-amino-3,7-dideoxy-D-threo-hept-6-ulosonate synthase.
• Reaction: 1-deoxy-D-threo-hexo-2,5-diulose 6-phosphate + L-aspartate 4-semialdehyde = 2,3-dioxopropyl phosphate + 2-amino-2,3,7-trideoxy-D-lyxo-hept-6- ulosonate

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

Key reference

Biochemistry 46:10562-10571 (2007)

PubMed id: 17713928

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.

M.Morar, R.H.White, S.E.Ealick.

ABSTRACT

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.