PDBsum entry 6yhh

Hydrolase

PDB id: 6yhh

Contents

Protein chains

655 a.a.

Ligands

TRS ×2

GOL

Waters ×1544

PDB id:

6yhh

Name:

Hydrolase

Title:

X-ray structure of flavobacterium johnsoniae chitobiase (fjgh20)

Structure:

Beta-n-acetylglucosaminidase-like protein glycoside hydrolase family 20. Chain: a, b. Engineered: yes

Source:

Flavobacterium johnsoniae (strain atcc 17061 / dsm 2064 / uw101). Organism_taxid: 376686. Strain: atcc 17061 / dsm 2064 / uw101. Gene: fjoh_4556. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008

Resolution:

1.70Å R-factor: 0.144 R-free: 0.175

Authors:

S.Mazurkewich,R.Helland,A.Mackenzie,V.G.H.Eijsink,P.B.Pope,G.Branden, J.Larsbrink

Key ref:

S.Mazurkewich et al. (2020). Structural insights of the enzymes from the chitin utilization locus of Flavobacterium johnsoniae. Sci Rep, 10, 13775. PubMed id: 32792608 DOI: 10.1038/s41598-020-70749-w

Date:

30-Mar-20 Release date: 02-Sep-20

Protein chains

A5FB64  (A5FB64_FLAJ1) -  beta-N-acetylhexosaminidase from Flavobacterium johnsoniae (strain ATCC 17061 / DSM 2064 / JCM 8514 / NBRC 14942 / NCIMB 11054 / UW101)

Seq: 688 a.a.

Struc: 655 a.a.

Enzyme reactions

• Enzyme class: E.C.3.2.1.52 - beta-N-acetylhexosaminidase.
• Reaction: Hydrolysis of terminal non-reducing N-acetyl-D-hexosamine residues in N-acetyl-beta-D-hexosaminides.

DOI no: 10.1038/s41598-020-70749-w

Sci Rep 10:13775 (2020)

PubMed id: 32792608

Structural insights of the enzymes from the chitin utilization locus of Flavobacterium johnsoniae.

S.Mazurkewich, R.Helland, A.Mackenzie, V.G.H.Eijsink, P.B.Pope, G.Brändén, J.Larsbrink.

ABSTRACT

Chitin is one of the most abundant renewable organic materials found on earth. The chitin utilization locus in Flavobacterium johnsoniae, which encodes necessary proteins for complete enzymatic depolymerization of crystalline chitin, has recently been characterized but no detailed structural information on the enzymes was provided. Here we present protein structures of the F. johnsoniae chitobiase (FjGH20) and chitinase B (FjChiB). FjGH20 is a multi-domain enzyme with a helical domain not before observed in other chitobiases and a domain organization reminiscent of GH84 (β-N-acetylglucosaminidase) family members. The structure of FjChiB reveals that the protein lacks loops and regions associated with exo-acting activity in other chitinases and instead has a more solvent accessible substrate binding cleft, which is consistent with its endo-chitinase activity. Additionally, small angle X-ray scattering data were collected for the internal 70 kDa region that connects the N- and C-terminal chitinase domains of the unique 158 kDa multi-domain chitinase A (FjChiA). The resulting model of the molecular envelope supports bioinformatic predictions of the region comprising six domains, each with similarities to either Fn3-like or Ig-like domains. Taken together, the results provide insights into chitin utilization by F. johnsoniae and reveal structural diversity in bacterial chitin metabolism.