2GPT

Crystal structure of Arabidopsis Dehydroquinate dehydratase-shikimate dehydrogenase in complex with tartrate and shikimate

Summary for 2GPT

• Entry DOI: 10.2210/pdb2gpt/pdb
• Descriptor: 3-dehydroquinate dehydratase/ shikimate 5-dehydrogenase, SULFATE ION, L(+)-TARTARIC ACID, ... (5 entities in total)
• Functional Keywords: type i dehydroquinate dehydratase, aroe, shikimate dehydrogenase, arabidopsis thaliana, shikimate, tartrate, bifunctional enzyme, oxidoreductase, lyase
• Biological source: Arabidopsis thaliana (thale cress)
• Cellular location: Plastid, chloroplast (Potential): Q9SQT8
• Total number of polymer chains: 1
• Total formula weight: 57605.32

Authors

Singh, S.A.,Christendat, D. (deposition date: 2006-04-18, release date: 2006-06-06, Last modification date: 2024-02-14)

Primary citation

Singh, S.A.,Christendat, D.
Structure of Arabidopsis dehydroquinate dehydratase-shikimate dehydrogenase and implications for metabolic channeling in the shikimate pathway
Biochemistry, 45:7787-7796, 2006

PubMed Abstract: The bifunctional enzyme dehydroquinate dehydratase-shikimate dehydrogenase (DHQ-SDH) catalyzes the dehydration of dehydroquinate to dehydroshikimate and the reduction of dehydroshikimate to shikimate in the shikimate pathway. We report the first crystal structure of Arabidopsis DHQ-SDH with shikimate bound at the SDH site and tartrate at the DHQ site. The interactions observed in the DHQ-tartrate complex reveal a conserved mode for substrate binding between the plant and microbial DHQ dehydratase family of enzymes. The SDH-shikimate complex provides the first direct evidence of the role of active site residues in the catalytic mechanism. Site-directed mutagenesis and mechanistic analysis revealed that Asp 423 and Lys 385 are key catalytic groups and Ser 336 is a key binding group. The arrangement of the two functional domains reveals that the control of metabolic flux through the shikimate pathway is achieved by increasing the effective concentration of dehydroshikimate through the proximity of the two sites.

PubMed: 16784230
DOI: 10.1021/bi060366+

Experimental method

X-RAY DIFFRACTION (1.95 Å)