Skip to main content
eScholarship
Open Access Publications from the University of California

UC Berkeley

UC Berkeley Previously Published Works bannerUC Berkeley

Broad‐specificity GH131 β‐glucanases are a hallmark of fungi and oomycetes that colonize plants

Abstract

Plant-tissue-colonizing fungi fine-tune the deconstruction of plant-cell walls (PCW) using different sets of enzymes according to their lifestyle. However, some of these enzymes are conserved among fungi with dissimilar lifestyles. We identified genes from Glycoside Hydrolase family GH131 as commonly expressed during plant-tissue colonization by saprobic, pathogenic and symbiotic fungi. By searching all the publicly available genomes, we found that GH131-coding genes were widely distributed in the Dikarya subkingdom, except in Taphrinomycotina and Saccharomycotina, and in phytopathogenic Oomycetes, but neither other eukaryotes nor prokaryotes. The presence of GH131 in a species was correlated with its association with plants as symbiont, pathogen or saprobe. We propose that GH131-family expansions and horizontal-gene transfers contributed to this adaptation. We analysed the biochemical activities of GH131 enzymes whose genes were upregulated during plant-tissue colonization in a saprobe (Pycnoporus sanguineus), a plant symbiont (Laccaria bicolor) and three hemibiotrophic-plant pathogens (Colletotrichum higginsianum, C. graminicola, Zymoseptoria tritici). These enzymes were all active on substrates with β-1,4, β-1,3 and mixed β-1,4/1,3 glucosidic linkages. Combined with a cellobiohydrolase, GH131 enzymes enhanced cellulose degradation. We propose that secreted GH131 enzymes unlock the PCW barrier and allow further deconstruction by other enzymes during plant tissue colonization by symbionts, pathogens and saprobes.

Many UC-authored scholarly publications are freely available on this site because of the UC's open access policies. Let us know how this access is important for you.

Main Content
For improved accessibility of PDF content, download the file to your device.
Current View