Selective xyloglucan oligosaccharide hydrolysis by a GH31 α-xylosidase from Escherichia coli.
Carbohydr Polym
; 284: 119150, 2022 May 15.
Article
en En
| MEDLINE
| ID: mdl-35287891
ABSTRACT
Xyloglucan is ubiquitous in the cell walls of land plants and is also an essential storage polymer in seeds of many species. We studied the hydrolysis of the non-reducing end xylosyl residue of xyloglucan oligosaccharides (XGOs) by the Escherichia coli α-xylosidase (YicI). Electrospray Ionization Tandem Mass Spectrometry (ESI-MS/MS) and ion fragmentation analysis together with high performance anion exchange chromatography with pulsed amperometric detection revealed that YicI preferentially removes the xylosyl residue from the glycosyl residue of non-galactosylated oligosaccharides. The YicI shows decreasing activity against the galactosylated oligosaccharides XXXG>XXLG≥XLXG. Studies of the XGOs interaction with active site residues by molecular dynamics simulations suggested that hydrogen bond interactions between the D49 and galactosylated oligosaccharides play an important role in enzyme-XGO interactions. This was confirmed by site-directed mutagenesis, where the D49A mutant affected catalytic efficiency against galactosylated XGOs. Our findings advance xyloglucan disassembly models and highlight the importance of YicI for biotechnology applications.
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Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Escherichia coli
/
Espectrometría de Masas en Tándem
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Carbohydr Polym
Año:
2022
Tipo del documento:
Article