5CCU

Crystal structure of endoglycoceramidase I from Rhodococ-cus equi


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.11 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.184 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural Insights into the Broad Substrate Specificity of a Novel Endoglycoceramidase I Belonging to a New Subfamily of GH5 Glycosidases

Han, Y.B.Chen, L.Q.Li, Z.Tan, Y.M.Feng, Y.Yang, G.Y.

(2017) J. Biol. Chem. 292: 4789-4800

  • DOI: 10.1074/jbc.M116.763821
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Endoglycoceramidases (EGCases) specifically hydrolyze the glycosidic linkage between the oligosaccharide and the ceramide moieties of various glycosphingolipids, and they have received substantial attention in the emerging field of glycosphingolipido ...

    Endoglycoceramidases (EGCases) specifically hydrolyze the glycosidic linkage between the oligosaccharide and the ceramide moieties of various glycosphingolipids, and they have received substantial attention in the emerging field of glycosphingolipidology. However, the mechanism regulating the strict substrate specificity of these GH5 glycosidases has not been identified. In this study, we report a novel EGCase I from Rhodococcus equi 103S (103S_EGCase I) with remarkably broad substrate specificity. Based on phylogenetic analyses, the enzyme may represent a new subfamily of GH5 glycosidases. The X-ray crystal structures of 103S_EGCase I alone and in complex with its substrates monosialodihexosylganglioside (GM3) and monosialotetrahexosylganglioside (GM1) enabled us to identify several structural features that may account for its broad specificity. Compared with EGCase II from Rhodococcus sp. M-777 (M777_EGCase II), which possesses strict substrate specificity, 103S_EGCase I possesses a longer α7-helix and a shorter loop 4, which forms a larger substrate-binding pocket that could accommodate more extended oligosaccharides. In addition, loop 2 and loop 8 of the enzyme adopt a more open conformation, which also enlarges the oligosaccharide-binding cavity. Based on this knowledge, a rationally designed experiment was performed to examine the substrate specificity of EGCase II. The truncation of loop 4 in M777_EGCase II increased its activity toward GM1 (163%). Remarkably, the S63G mutant of M777_EGCase II showed a broader substrate spectra and significantly increased activity toward bulky substrates (up to >1370-fold for fucosyl-GM1). Collectively, the results presented here reveal the exquisite substrate recognition mechanism of EGCases and provide an opportunity for further engineering of these enzymes.


    Organizational Affiliation

    From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.,the Shanghai Collaborative Innovation Center for Biomanufacturing (SCICB), East China University of Science and Technology, Shanghai 200237, China.,the Shanghai Institute for Advanced Immunological Studies, ShanghaiTech University, Shanghai 200031, China, and.,From the State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China, yanggy@sjtu.edu.cn.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Putative secreted endoglycosylceramidase
A, B
500Rhodococcus hoagii (strain 103S)Mutation(s): 0 
Find proteins for A0A3S5YBC7 (Rhodococcus hoagii (strain 103S))
Go to UniProtKB:  A0A3S5YBC7
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
NA
Query on NA

Download SDF File 
Download CCD File 
A
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
EDO
Query on EDO

Download SDF File 
Download CCD File 
A, B
1,2-ETHANEDIOL
ETHYLENE GLYCOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.11 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.184 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 192.841α = 90.00
b = 48.980β = 114.30
c = 120.304γ = 90.00
Software Package:
Software NamePurpose
MOLREPphasing
REFMACrefinement
HKL-2000data reduction
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2015-07-02 
  • Released Date: 2015-09-02 
  • Deposition Author(s): Chen, L.

Revision History 

  • Version 1.0: 2015-09-02
    Type: Initial release
  • Version 1.1: 2017-04-05
    Type: Database references