Comparison of different crystal forms of 3-dehydroquinase from Salmonella typhi and its implication for the enzyme activity.

The type I 3-dehydroquinate dehydratase (DHQase) which catalyses the reversible dehydration of 3-dehydroquinic acid to 3-dehydroshikimic acid is involved in the shikimate pathway for the biosynthesis of aromatic compounds. The shikimate pathway is absent in mammals, which makes structural information about DHQase vital for the rational design of antimicrobial drugs and herbicides. The crystallographic structure of the type I DHQase from Salmonella typhi has now been determined for the native form at 1.78 A resolution (R = 19.9%; R(free) = 24.7%). The structure of the modified enzyme to which the product has been covalently bound has also been determined but in a different crystal form (2.1 A resolution; R = 17.7%; R(free) = 24.5%). An analysis of the three available crystal forms has provided information about the physiological dimer interface. The enzyme relies upon the closure of a lid-like loop to complete its active site. As the lid-loop tends to stay in the closed position, dimerization appears to play a role in biasing the arrangement of the loop towards its open position, thus facilitating substrate access.
AuthorsWen-Hwa Lee, Luis Augusto Perles, Ronaldo A P Nagem, Annette K Shrive, Alastair Hawkins, Lindsay Sawyer, Igor Polikarpov
JournalActa crystallographica. Section D, Biological crystallography (Acta Crystallogr D Biol Crystallogr) Vol. 58 Issue Pt 5 Pg. 798-804 (May 2002) ISSN: 0907-4449 [Print] Denmark
PMID11976491 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • Protein Subunits
  • Hydro-Lyases
  • 3-dehydroquinate dehydratase
  • Binding Sites
  • Crystallization
  • Crystallography, X-Ray
  • Dimerization
  • Hydro-Lyases (chemistry, metabolism)
  • Hydrogen Bonding
  • Models, Molecular
  • Protein Binding
  • Protein Structure, Quaternary
  • Protein Subunits
  • Salmonella typhi (enzymology)
  • Structure-Activity Relationship

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!

Choose Username:
Verify Password: