Crystal structure of lacto-N-biosidase BsaX from Bifidobacterium saguini, lacto-N-biose complex

Experimental Data Snapshot

  • Resolution: 2.51 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.157 
  • R-Value Observed: 0.160 

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Crystal structures of glycoside hydrolase family 136 lacto-N-biosidases from monkey gut- and human adult gut bacteria.

Yamada, C.Katayama, T.Fushinobu, S.

(2022) Biosci Biotechnol Biochem 86: 464-475

  • DOI: https://doi.org/10.1093/bbb/zbac015
  • Primary Citation of Related Structures:  
    7V6I, 7V6M

  • PubMed Abstract: 

    Glycoside hydrolase family 136 (GH136) was established after the discovery and structural analysis of lacto-N-biosidase (LNBase) from the infant gut bacterium Bifidobacterium longum subsp. longum JCM1217 (BlLnbX). Homologous genes of BlLnbX are widely distributed in the genomes of human gut bacteria and monkey Bifidobacterium spp., although only 2 crystal structures were reported in the GH136 family. Cell suspensions of Bifidobacterium saguini, Tyzzerella nexilis, and Ruminococcus lactaris exhibited the LNBase activity. Recombinant LNBases of these 3 species were functionally expressed with their specific chaperones in Escherichia coli, and their kinetic parameters against p-nitrophenol substrates were determined. The crystal structures of the LNBases from B. saguini and T. nexilis in complex with lacto-N-biose I were determined at 2.51 and 1.92 Å resolutions, respectively. These structures conserve a β-helix fold characteristic of GH136 and the catalytic residues, but they lack the metal ions that were present in BlLnbX.

  • Organizational Affiliation

    Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Lacto-N-biosidase620Bifidobacterium saguini DSM 23967Mutation(s): 0 
Gene Names: BISA_2023
Find proteins for A0A087D8U9 (Bifidobacterium saguini DSM 23967)
Explore A0A087D8U9 
Go to UniProtKB:  A0A087D8U9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupA0A087D8U9
Sequence Annotations
  • Reference Sequence


Entity ID: 2
MoleculeChains Length2D Diagram Glycosylation3D Interactions
Glycosylation Resources
GlyTouCan:  G00056MO
GlyCosmos:  G00056MO
GlyGen:  G00056MO
Experimental Data & Validation

Experimental Data

  • Resolution: 2.51 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.157 
  • R-Value Observed: 0.160 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 113.24α = 90
b = 113.24β = 90
c = 79.097γ = 120
Software Package:
Software NamePurpose
XDSdata reduction
Aimlessdata scaling

Structure Validation

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Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
Japan Society for the Promotion of Science (JSPS)Japan16J09251
Japan Society for the Promotion of Science (JSPS)Japan18K14388

Revision History  (Full details and data files)

  • Version 1.0: 2022-02-09
    Type: Initial release
  • Version 1.1: 2022-04-06
    Changes: Database references
  • Version 1.2: 2023-11-29
    Changes: Data collection, Refinement description