Biology subjects

Cervone, F.

Publications and source records attributed to Cervone, F..

3 recordsLinked to original sources

bioRxiv2024

Berberine Bridge enzyme-like oxidases orchestrate homeostatic control and signaling of oligogalacturonides in defense and wounding

Plant immunity is triggered by endogenous elicitors known as damage-associated molecular patterns (DAMPs). Oligogalacturonides (OGs) are DAMPs released from the cell wall (CW) demethylated homogalacturonan during microbial colonization, mechanical or pest-provoked tissue damage, and physiological CW remodeling. Berberine Bridge Enzyme-like (BBE-l) proteins named OG oxidases (OGOXs) have been proposed to govern OGs homeostasis, which is necessary to avoid deleterious growth-affecting hyper-immunity and possible cell death. Using OGOX1 over-expressing lines and ogox1/2 double mutants, we show that these enzymes determine the levels of active OGs vs. inactive oxidized products (oxOGs). The ogox1/2-deficient plants have elevated levels of OGs, while plants overexpressing OGOX1 accumulate oxOGs. The balance between OGs and oxOGs affect disease resistance against Pseudomonas syringae pv tomato, Pectobacterium carotovorum, and Botrytis cinerea depending on the microbial capacity to respond to OGs and metabolize oxOGs. Gene expression upon plant infiltration with OGs reveals that OGOXs orchestrate OG signaling in defense as well as upon tissue damage, pointing to these enzymes as apoplastic players in immunity and tissue repair. TeaserOxidases control the homeostasis of oligogalacturonides in the cell wall and play a pivotal role in the plant immunity.

plant biology↗

bioRxiv2023

BERBERINE BRIDGE ENZYME-LIKE OXIDASES OF CELLODEXTRINS AND MIXED-LINKED β-GLUCANS CONTROL SEED COAT FORMATION

A member of the Arabidopsis Berberine Bridge Enzyme-like (BBE-l) protein family named CELLODEXTRIN OXIDASE 2 (CELLOX2) has been characterized in this paper and shown to display structural and enzymatic features similar to the previously characterized CELLOX1. These include the capability to oxidize the mixed-linked {beta}-1[->]3/{beta}-1[->]4-glucans (MLGs), recently described as cell wall-derived damage-associated molecular patterns (DAMPs) that activate plant immunity. The two paralogous genes show a different expression profile. Unlike CELLOX1, CELLOX2 is not expressed in seedlings or in adult plants and is not involved in immunity against Botrytis cinerea. Both genes are expressed in a concerted manner in the seed coat during development: whereas CELLOX2 transcripts are detected mainly during the heart stage, CELLOX1 transcripts are detected later, when the expression of CELLOX2 decreases. Analysis of seeds of cellox1 and cellox2 knock-out mutants show alterations in the structure of the coat and mucilage, but not in their monosaccharide composition. We propose that the cell wall structure of specific organs is not only the result of a coordinated synthesis/degradation of polysaccharides but also of their exposure to enzymatic oxidation. Our results also reinforce the view that the family of BBE-l proteins is at least in part devoted to the control of the activity of cell wall-derived oligosaccharides acting as DAMPs. SENTENCETwo Arabidopsis BBE-like oxidases of the cell wall DAMPs cellodextrins and mixed-linked {beta}-glucans inactivate their elicitor activity. Seed coat and mucilage are altered in null mutants of two enzymes.

plant biology↗

bioRxiv2022

Berberine Bridge Enzyme-Like Oligosaccharide Oxidases Act As Enzymatic Transducers Between Microbial Glycoside Hydrolases And Plant Peroxidases

OG-oxidases (OGOXs) and CD-oxidase (CELLOX) are plant berberine bridge enzyme-like oligosaccharide oxidases that oxidize oligogalacturonides (OGs) and cellodextrins (CDs), cell wall fragments with nature of damage-associated molecular patterns (DAMPs). The oxidation of OGs and CDs attenuates their elicitor activity by concomitantly releasing H2O2. Here, we demonstrate that the H2O2 generated downstream of the combined action between a fungal polygalacturonase and OGOX1 or an endoglucanase and CELLOX can be directed by plant peroxidases (PODs) either towards a reaction possibly involved in plant defence such as the oxidation of monolignol or a reaction possibly involved in a developmental event such as the oxidation of auxin (IAA), pointing to OGOX1 and CELLOX as enzymatic transducers between microbial glycoside hydrolases and plant PODs.

plant biology↗