1i75
CRYSTAL STRUCTURE OF CYCLODEXTRIN GLUCANOTRANSFERASE FROM ALKALOPHILIC BACILLUS SP.#1011 COMPLEXED WITH 1-DEOXYNOJIRIMYCIN
| |||||||
| , resolution 2.0Å | |||||||
|---|---|---|---|---|---|---|---|
| Ligands: | , | ||||||
| Gene: | BACCGTA (Bacillus sp.) | ||||||
| Activity: | Cyclomaltodextrin glucanotransferase, with EC number 2.4.1.19 | ||||||
| Related: | 1PAM
| ||||||
| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
OverviewOverview
1-Deoxynojirimycin, a pseudo-monosaccharide, is a strong inhibitor of glucoamylase but a relatively weak inhibitor of cyclodextrin glucanotransferase (CGTase). To elucidate this difference, the crystal structure of the CGTase from alkalophilic Bacillus sp. 1011 complexed with 1-deoxynojirimycin was determined at 2.0 A resolution with the crystallographic R value of 0.154 (R(free) = 0.214). The asymmetric unit of the crystal contains two CGTase molecules and each molecule binds two 1-deoxynojirimycins. One 1-deoxynojirimycin molecule is bound to the active center by hydrogen bonds with catalytic residues and water molecules, but its binding mode differs from that expected in the substrate binding. Another 1-deoxynojirimycin found at the maltose-binding site 1 is bound to Asn-667 with a hydrogen bond and by stacking interaction with the indole moiety of Trp-662 of molecule 1 or Trp-616 of molecule 2. Comparison of this structure with that of the acarbose-CGTase complex suggested that the lack of stacking interaction with the aromatic side chain of Tyr-100 is responsible for the weak inhibition by 1-deoxynojirimycin of the enzymatic action of CGTase.
About this StructureAbout this Structure
1I75 is a Single protein structure of sequence from Bacillus sp.. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of cyclodextrin glucanotransferase from alkalophilic Bacillus sp. 1011 complexed with 1-deoxynojirimycin at 2.0 A resolution., Kanai R, Haga K, Yamane K, Harata K, J Biochem. 2001 Apr;129(4):593-8. PMID:11275559
Page seeded by OCA on Sun Mar 30 21:15:33 2008