Title
Multi-omic analyses of extensively decayed Pinus contorta reveal expression of diverse array of lignocellulose degrading enzymes
Department/School
Biology
Date
2018
Document Type
Article
Keywords
Pinus, brown rot, metaproteome, metatranscriptome, white rot
DOI
DOI: 10.1128/AEM.01133-18
Abstract
Fungi play a key role cycling nutrients in forest ecosystems, but the mechanisms remain uncertain. To clarify the enzymatic processes involved in wood decomposition, the metatranscriptomics and metaproteomics of extensively decayed lodgepole pine were examined by RNA sequencing (RNA-seq) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), respectively. Following de novo metatranscriptome assembly, 52,011 contigs were searched for functional domains and homology to database entries. Contigs similar to basidiomycete transcripts dominated, and many of these were most closely related to ligninolytic white rot fungi or cellulolytic brown rot fungi. A diverse array of carbohydrate-active enzymes (CAZymes) representing a total of 132 families or subfamilies were identified. Among these were 672 glycoside hydrolases, including highly expressed cellulases or hemicellulases. The CAZymes also included 162 predicted redox enzymes classified within auxiliary activity (AA) families. Eighteen of these were manganese peroxidases, which are key components of ligninolytic white rot fungi. The expression of other redox enzymes supported the working of hydroquinone reduction cycles capable of generating reactive hydroxyl radicals. These have been implicated as diffusible oxidants responsible for cellulose depolymerization by brown rot fungi. Thus, enzyme diversity and the coexistence of brown and white rot fungi suggest complex interactions of fungal species and degradative strategies during the decay of lodgepole pine.
Volume
84
Issue
20
Published in
Applied and Environmental Microbiology
Citation/Other Information
Hori C, Gaskell J, Cullen D, Sabat G, Stewart PE, Lail K, Peng Y, Barry K, Grigoriev IV, Kohler A, Fauchery L, Martin F, Zeiner CA, Bhatnagar JM. 2018. Multi-omic analyses of extensively decayed Pinus contorta reveal expression of diverse array of lignocellulose degrading enzymes. Applied and Environmental Microbiology, DOI: 10.1128/AEM.01133-18.