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PDBsum entry 1kck

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protein ligands metals links
Transferase PDB id
1kck
Jmol
Contents
Protein chain
686 a.a. *
Ligands
GLC-G6D-ADH
GLC-GLC
GLC
GLC-GLC-GLC
BGC-GLC-GLC
Metals
_CA ×2
Waters ×433
* Residue conservation analysis
PDB id:
1kck
Name: Transferase
Title: Bacillus circulans strain 251 cyclodextrin glycosyl transferase mutant n193g
Structure: Cyclodextrin glycosyltransferase. Chain: a. Synonym: cyclomaltodextrin glucanotransferase. Engineered: yes. Mutation: yes
Source: Bacillus circulans. Organism_taxid: 1397. Strain: 251. Expressed in: escherichia coli. Expression_system_taxid: 562.
Resolution:
2.43Å     R-factor:   0.159     R-free:   0.205
Authors: H.J.Rozeboom,J.C.M.Uitdehaag,B.W.Dijkstra
Key ref:
H.Leemhuis et al. (2002). The remote substrate binding subsite -6 in cyclodextrin-glycosyltransferase controls the transferase activity of the enzyme via an induced-fit mechanism. J Biol Chem, 277, 1113-1119. PubMed id: 11696539 DOI: 10.1074/jbc.M106667200
Date:
09-Nov-01     Release date:   16-Jan-02    
PROCHECK
Go to PROCHECK summary
 Headers
 References

Protein chain
Pfam   ArchSchema ?
P43379  (CDGT2_BACCI) -  Cyclomaltodextrin glucanotransferase
Seq:
Struc:
 
Seq:
Struc:
713 a.a.
686 a.a.*
Key:    PfamA domain  Secondary structure  CATH domain
* PDB and UniProt seqs differ at 1 residue position (black cross)

 Enzyme reactions 
   Enzyme class: E.C.2.4.1.19  - Cyclomaltodextrin glucanotransferase.
[IntEnz]   [ExPASy]   [KEGG]   [BRENDA]
      Reaction: Degrades starch to cyclodextrins by formation of a 1,4-alpha-D- glucosidic bond.
 Gene Ontology (GO) functional annotation 
  GO annot!
  Cellular component     extracellular region   1 term 
  Biological process     carbohydrate metabolic process   1 term 
  Biochemical function     catalytic activity     8 terms  

 

 
DOI no: 10.1074/jbc.M106667200 J Biol Chem 277:1113-1119 (2002)
PubMed id: 11696539  
 
 
The remote substrate binding subsite -6 in cyclodextrin-glycosyltransferase controls the transferase activity of the enzyme via an induced-fit mechanism.
H.Leemhuis, J.C.Uitdehaag, H.J.Rozeboom, B.W.Dijkstra, L.Dijkhuizen.
 
  ABSTRACT  
 
Cyclodextrin-glycosyltransferase (CGTase) catalyzes the formation of alpha-, beta-, and gamma-cyclodextrins (cyclic alpha-(1,4)-linked oligosaccharides of 6, 7, or 8 glucose residues, respectively) from starch. Nine substrate binding subsites were observed in an x-ray structure of the CGTase from Bacillus circulans strain 251 complexed with a maltononaose substrate. Subsite -6 is conserved in CGTases, suggesting its importance for the reactions catalyzed by the enzyme. To investigate this in detail, we made six mutant CGTases (Y167F, G179L, G180L, N193G, N193L, and G179L/G180L). All subsite -6 mutants had decreased k(cat) values for beta-cyclodextrin formation, as well as for the disproportionation and coupling reactions, but not for hydrolysis. Especially G179L, G180L, and G179L/G180L affected the transglycosylation activities, most prominently for the coupling reactions. The results demonstrate that (i) subsite -6 is important for all three CGTase-catalyzed transglycosylation reactions, (ii) Gly-180 is conserved because of its importance for the circularization of the linear substrates, (iii) it is possible to independently change cyclization and coupling activities, and (iv) substrate interactions at subsite -6 activate the enzyme in catalysis via an induced-fit mechanism. This article provides for the first time definite biochemical evidence for such an induced-fit mechanism in the alpha-amylase family.
 
  Selected figure(s)  
 
Figure 1.
Fig. 1. A, schematic overview of the interactions between the B. circulans strain 251 CGTase and a maltononaose substrate. For clarity not all interactions at subsites +1, 1, and 2 are shown (21). B, maltononaose (black) conformation in the active site of CGTase. The arrow indicates the cleavage site. B was made using Swiss-PDB-Viewer (41).
Figure 2.
Fig. 2. Production of cyclodextrins (g/liter) from 10% (w/v) pregelatinized starch by the action of (mutant) B. circulans strain 251 CGTases. circle , , and indicate -, -, and -cyclodextrin, respectively. WT, wild-type.
 
  The above figures are reprinted by permission from the ASBMB: J Biol Chem (2002, 277, 1113-1119) copyright 2002.  

Literature references that cite this PDB file's key reference

  PubMed id Reference
19763564 H.Leemhuis, R.M.Kelly, and L.Dijkhuizen (2010).
Engineering of cyclodextrin glucanotransferases and the impact for biotechnological applications.
  Appl Microbiol Biotechnol, 85, 823-835.  
19706511 J.P.Schwans, D.A.Kraut, and D.Herschlag (2009).
Determining the catalytic role of remote substrate binding interactions in ketosteroid isomerase.
  Proc Natl Acad Sci U S A, 106, 14271-14275.  
19224571 M.Fiedorowicz, G.Khachatryan, A.Konieczna-Molenda, and P.Tomasik (2009).
Formation of cyclodextrins with cyclodextrin glucosyltransferase stimulated with polarized light.
  Biotechnol Prog, 25, 147-150.  
19367403 R.M.Kelly, L.Dijkhuizen, and H.Leemhuis (2009).
The evolution of cyclodextrin glucanotransferase product specificity.
  Appl Microbiol Biotechnol, 84, 119-133.  
16151092 T.Kaper, B.Talik, T.J.Ettema, H.Bos, M.J.van der Maarel, and L.Dijkhuizen (2005).
Amylomaltase of Pyrobaculum aerophilum IM2 produces thermoreversible starch gels.
  Appl Environ Microbiol, 71, 5098-5106.  
12492486 H.Leemhuis, B.W.Dijkstra, and L.Dijkhuizen (2003).
Thermoanaerobacterium thermosulfurigenes cyclodextrin glycosyltransferase.
  Eur J Biochem, 270, 155-162.  
The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time.