5GMA

Crystal structure of the P228A variant of Thermotoga maritima acetyl esterase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.214 
  • R-Value Work: 0.176 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Structural role of a conserved active site cis proline in the Thermotoga maritima acetyl esterase from the carbohydrate esterase family 7

Singh, M.K.Manoj, N.

(2017) Proteins 85: 694-708

  • DOI: 10.1002/prot.25249

  • PubMed Abstract: 
  • A conserved cis proline residue located in the active site of Thermotoga maritima acetyl esterase (TmAcE) from the carbohydrate esterase family 7 (CE7) has been substituted by alanine. The residue was known to play a crucial role in determining the c ...

    A conserved cis proline residue located in the active site of Thermotoga maritima acetyl esterase (TmAcE) from the carbohydrate esterase family 7 (CE7) has been substituted by alanine. The residue was known to play a crucial role in determining the catalytic properties of the enzyme. To elucidate the structural role of the residue, the crystal structure of the Pro228Ala variant (TmAcE P228A ) was determined at 2.1 Å resolution. The replacement does not affect the overall secondary, tertiary, and quaternary structures and moderately decreases the thermal stability. However, the wild type cis conformation of the 227-228 peptide bond adopts a trans conformation in the variant. Other conformational changes in the tertiary structure are restricted to residues 222-226, preceding this peptide bond and are located away from the active site. Overall, the results suggest that the conserved proline residue is responsible for the cis conformation of the peptide and shapes the geometry of the active site. Elimination of the pyrrolidine ring results in the loss of van der Waals and hydrophobic interactions with both the alcohol and acyl moeities of the ester substrate, leading to significant impairment of the activity and perturbation of substrate specificity. Furthermore, a cis-to-trans conformational change arising out of residue changes at this position may be associated with the evolution of divergent activity, specificity, and stability properties of members constituting the CE7 family. Proteins 2017; 85:694-708. © 2016 Wiley Periodicals, Inc.


    Related Citations: 
    • Crystal structure of Thermotoga maritima acetyl esterase complex with a substrate analog: Insights into the distinctive substrate specificity in the CE7 carbohydrate esterase family.
      Singh, M.K.,Manoj, N.
      (2016) Biochem. Biophys. Res. Commun. 476: 63
    • An extended loop in CE7 carbohydrate esterase family is dispensable for oligomerization but required for activity and thermostability.
      Singh, M.K.,Manoj, N.
      (2016) J. Struct. Biol. 194: 434


    Organizational Affiliation

    Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai, 600036, Tamil Nadu, India.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Cephalosporin-C deacetylase
A, B, C, D, E, F
337Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099)Mutation(s): 1 
Gene Names: axeA
EC: 3.1.1.41
Find proteins for Q9WXT2 (Thermotoga maritima (strain ATCC 43589 / MSB8 / DSM 3109 / JCM 10099))
Go to UniProtKB:  Q9WXT2
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ACT
Query on ACT

Download SDF File 
Download CCD File 
C, D, E
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.214 
  • R-Value Work: 0.176 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 89.760α = 90.00
b = 115.690β = 110.21
c = 103.240γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
MOLREPphasing
Aimlessdata scaling
iMOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data

  • Deposited Date: 2016-07-13 
  • Released Date: 2017-06-21 
  • Deposition Author(s): Manoj, N.

Funding OrganizationLocationGrant Number
Department of BiotechnologyIndiaBT/PR13805/PID/06/550/2010

Revision History 

  • Version 1.0: 2017-06-21
    Type: Initial release