3WMS

The crystal structure of Y195I mutant alpha-cyclodextrin glycosyltransferase from Paenibacillus macerans


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.173 

wwPDB Validation 3D Report Full Report


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Literature

Structural basis of a mutant Y195I alpha-cyclodextrin glycosyltransferase with switched product specificity from alpha-cyclodextrin to beta-/ gamma-cyclodextrin

Xie, T.Hou, Y.J.Li, D.F.Yue, Y.Qian, S.J.Chao, Y.P.

(2014) J.Biotechnol. 182-183: 92-96

  • DOI: 10.1016/j.jbiotec.2014.03.014

  • PubMed Abstract: 
  • Cyclodextrin glycosyltransferase (EC 2.4.1.19) (CGTase) is an extracellular bacterial enzyme which has the unique capability of forming cyclodextrins from starch. Our previous investigation revealed that a mutant Y195I α-CGTase drastically altered th ...

    Cyclodextrin glycosyltransferase (EC 2.4.1.19) (CGTase) is an extracellular bacterial enzyme which has the unique capability of forming cyclodextrins from starch. Our previous investigation revealed that a mutant Y195I α-CGTase drastically altered the cyclodextrin specificity by switching toward the synthesis of both β- and γ-CDs (Xie et al., 2013a,b). In this study, we determined one X-ray structure of the mutant Y195I α-CGTase at 2.3Å. The overall structure was similar to that of the typical β-CGTase from Bacillus circulans 251, with minor difference in flexible domains since they showed about 70% homogeneity of amino acid sequences. The central site with isoleucine tended to be more flexible than tyrosine thus made the sugar chain, during the cyclization process, form a larger cyclodextrin like β- and γ-CDs surrounding the central site instead of α-CD. Superposition of the structure of Y195I α-CGTase with those of β-CGTase and γ-CGTase showed that residues Lys232, Lys89 and Arg177 at subsites +2, -3 and -7 could form smaller substrate binding cavity. In summary, the crystal structure revealed that moderate increase of mobility of the central site resulted in the switched product specificity from α-CD to β- and γ-CDs of the mutant Y195I α-CGTase. The space differences alongside the active domain may be another factor that impacts the product specificity of the CGTase.


    Organizational Affiliation

    State Key Laboratories of Transducer Technology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.,State Key Laboratories of Transducer Technology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University (BUAA), Beijing 100191, China.,National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Chaoyang District, Beijing 100101, China.,State Key Laboratories of Transducer Technology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China; CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China. Electronic address: chaoyp@sun.im.ac.cn.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Alpha-cyclodextrin glucanotransferase
A
726Paenibacillus maceransMutation(s): 1 
Gene Names: cgtM
EC: 2.4.1.19
Find proteins for P04830 (Paenibacillus macerans)
Go to UniProtKB:  P04830
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CA
Query on CA

Download SDF File 
Download CCD File 
A
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.221 
  • R-Value Work: 0.173 
  • Space Group: P 65
Unit Cell:
Length (Å)Angle (°)
a = 102.589α = 90.00
b = 102.589β = 90.00
c = 114.371γ = 120.00
Software Package:
Software NamePurpose
CrystalCleardata collection
PHASESphasing
PHENIXrefinement
SCALAdata scaling
MOSFLMdata reduction

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-11-12
    Type: Initial release