Structural and functional investigation of a fungal member of carbohydrate esterase family 15 with potential specificity for rare xylans.
Acta Crystallogr D Struct Biol
; 79(Pt 6): 545-555, 2023 Jun 01.
Article
en En
| MEDLINE
| ID: mdl-37227091
ABSTRACT
In plant cell walls, covalent bonds between polysaccharides and lignin increase recalcitrance to degradation. Ester bonds are known to exist between glucuronic acid moieties on glucuronoxylan and lignin, and these can be cleaved by glucuronoyl esterases (GEs) from carbohydrate esterase family 15 (CE15). GEs are found in both bacteria and fungi, and some microorganisms also encode multiple GEs, although the reason for this is still not fully clear. The fungus Lentithecium fluviatile encodes three CE15 enzymes, of which two have previously been heterologously produced, although neither was active on the tested model substrate. Here, one of these, LfCE15C, has been investigated in detail using a range of model and natural substrates and its structure has been solved using X-ray crystallography. No activity could be verified on any tested substrate, but biophysical assays indicate an ability to bind to complex carbohydrate ligands. The structure further suggests that this enzyme, which possesses an intact catalytic triad, might be able to bind and act on more extensively decorated xylan chains than has been reported for other CE15 members. It is speculated that rare glucuronoxylans decorated at the glucuronic acid moiety may be the true targets of LfCE15C and other CE15 family members with similar sequence characteristics.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Esterasas
/
Lignina
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Acta Crystallogr D Struct Biol
Año:
2023
Tipo del documento:
Article
País de afiliación:
Suecia