7B5V

The carbohydrate binding module family 48 (CBM48) and carboxy-terminal carbohydrate esterase family 1 (CE1) domains of the multidomain esterase DmCE1B from Dysgonomonas mossii

Summary for 7B5V

• Entry DOI: 10.2210/pdb7b5v/pdb
• Descriptor: Carbohydrate Esterase family 1 protein with an N-terminal carbohydrate binding module family 48, CHLORIDE ION, DI(HYDROXYETHYL)ETHER, ... (5 entities in total)
• Functional Keywords: carbohydrate esterase, ce1, cbm48, carbohydrate binding module, cbm, ce, pul, lignin, xylan, ferulate, ferouyl esterase, hydrolase
• Biological source: Dysgonomonas mossii DSM 22836
• Total number of polymer chains: 2
• Total formula weight: 86924.69

Authors

Mazurkewich, S.,Kmezik, C.,Branden, G.,Larsbrink, J. (deposition date: 2020-12-07, release date: 2021-03-10, Last modification date: 2024-01-31)

Primary citation

Kmezik, C.,Mazurkewich, S.,Meents, T.,McKee, L.S.,Idstrom, A.,Armeni, M.,Savolainen, O.,Branden, G.,Larsbrink, J.
A polysaccharide utilization locus from the gut bacterium Dysgonomonas mossii encodes functionally distinct carbohydrate esterases.
J.Biol.Chem., 296:100500-100500, 2021

PubMed Abstract: The gut microbiota plays a central role in human health by enzymatically degrading dietary fiber and concomitantly excreting short chain fatty acids that are associated with manifold health benefits. The polysaccharide xylan is abundant in dietary fiber but noncarbohydrate decorations hinder efficient cleavage by glycoside hydrolases (GHs) and need to be addressed by carbohydrate esterases (CEs). Enzymes from carbohydrate esterase families 1 and 6 (CE1 and 6) perform key roles in xylan degradation by removing feruloyl and acetate decorations, yet little is known about these enzyme families especially with regard to their diversity in activity. Bacteroidetes bacteria are dominant members of the microbiota and often encode their carbohydrate-active enzymes in multigene polysaccharide utilization loci (PULs). Here we present the characterization of three CEs found in a PUL encoded by the gut Bacteroidete Dysgonomonas mossii. We demonstrate that the CEs are functionally distinct, with one highly efficient CE6 acetyl esterase and two CE1 enzymes with feruloyl esterase activities. One multidomain CE1 enzyme contains two CE1 domains: an N-terminal domain feruloyl esterase, and a C-terminal domain with minimal activity on model substrates. We present the structure of the C-terminal CE1 domain with the carbohydrate-binding module that bridges the two CE1 domains, as well as a complex of the same protein fragment with methyl ferulate. The investment of D. mossii in producing multiple CEs suggests that improved accessibility of xylan for GHs and cleavage of covalent polysaccharide-polysaccharide and lignin-polysaccharide bonds are important enzyme activities in the gut environment.

PubMed: 33667545
DOI: 10.1016/j.jbc.2021.100500

Experimental method

X-RAY DIFFRACTION (1.7 Å)