A novel chicory fructanase can degrade common microbial fructan product profiles and displays positive cooperativity

Bibliographische Detailangaben
Veröffentlicht in:	Journal of experimental botany. - 1985. - 73(2022), 5 vom: 02. März, Seite 1602-1622
1. Verfasser:	Versluys, Maxime (VerfasserIn)
Weitere Verfasser:	Porras-Domínguez, Jaime Ricardo, De Coninck, Tibo, Van Damme, Els J M, Van den Ende, Wim
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2022
Zugriff auf das übergeordnete Werk:	Journal of experimental botany
Schlagworte:	Journal Article Research Support, Non-U.S. Gov't Chicory fructan signalling fructanase levan plant-microbe interaction Fructans Glycoside Hydrolases EC 3.2.1.- mehr... beta-Fructofuranosidase EC 3.2.1.26 levanase EC 3.2.1.65

Beschreibung
Zusammenfassung:	© The Author(s) 2021. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissionsoup.com. Fructan metabolism in bacteria and plants relies on fructosyltransferases and fructanases. Plant fructanases (fructan exohydrolase, FEH) only hydrolyse terminal fructose residues. Levan (β-2,6 linkages) is the most abundant fructan type in bacteria. Dicot fructan accumulators, such as chicory (Cichorium intybus), accumulate inulin (β-2,1 linkages), harbouring several 1-FEH isoforms for their degradation. Here, a novel chicory fructanase with high affinity for levan was characterized, providing evidence that such enzymes widely occur in higher plants. It is adapted to common microbial fructan profiles, but has low affinity towards chicory inulin, in line with a function in trimming of microbial fructans in the extracellular environment. Docking experiments indicate the importance of an N-glycosylation site close to the active site for substrate specificity. Optimal pH and temperature for levan hydrolysis are 5.0 and 43.7 °C, respectively. Docking experiments suggested multiple substrate binding sites and levan-mediated enzyme dimerization, explaining the observed positive cooperativity. Alignments show a single amino acid shift in the position of a conserved DXX(R/K) couple, typical for sucrose binding in cell wall invertases. A possible involvement of plant fructanases in levan trimming is discussed, in line with the emerging 'fructan detour' concepts, suggesting that levan oligosaccharides act as signalling entities during plant-microbial interactions
Beschreibung:	Date Completed 11.03.2022 Date Revised 09.01.2024 published: Print Citation Status MEDLINE
ISSN:	1460-2431
DOI:	10.1093/jxb/erab488