Comparative Analysis of Herbaceous and Woody Cell Wall Digestibility by Pathogenic Fungi

Molecules

Yan Yang¹  Jisheng Li²  Hao Fang²  Linfang Wei²  Johannes Liesche²  Yifan Wang²  Yanping Wei²  Yunheng Zhou²  Chen Zhao²  Yahong Wei²  Yisong Liu²  Shaolin Chen²  Yanhua Dou²  Panpan Du²  Nitesh Kumar Mund²  Lili Huang³ 

[1] College of Chemistry and Chemical Engineering, ShanxiDatong University, Datong 037009, China;College of Life Sciences, Northwest A&F University, Yangling, Xianyang 712100, China;College of Plant Protection, Northwest A&F University, Yangling, Xianyang 712100, China;

关键词: cellulose;    hemicelluloses;    lignin;    apple tree branch;    wheat straw;    rapeseed straw;   

DOI  :  10.3390/molecules26237220

来源: DOAJ

【 摘 要 】

Fungal pathogens have evolved combinations of plant cell-wall-degrading enzymes (PCWDEs) to deconstruct host plant cell walls (PCWs). An understanding of this process is hoped to create a basis for improving plant biomass conversion efficiency into sustainable biofuels and bioproducts. Here, an approach integrating enzyme activity assay, biomass pretreatment, field emission scanning electron microscopy (FESEM), and genomic analysis of PCWDEs were applied to examine digestibility or degradability of selected woody and herbaceous biomass by pathogenic fungi. Preferred hydrolysis of apple tree branch, rapeseed straw, or wheat straw were observed by the apple-tree-specific pathogen Valsa mali, the rapeseed pathogen Sclerotinia sclerotiorum, and the wheat pathogen Rhizoctonia cerealis, respectively. Delignification by peracetic acid (PAA) pretreatment increased PCW digestibility, and the increase was generally more profound with non-host than host PCW substrates. Hemicellulase pretreatment slightly reduced or had no effect on hemicellulose content in the PCW substrates tested; however, the pretreatment significantly changed hydrolytic preferences of the selected pathogens, indicating a role of hemicellulose branching in PCW digestibility. Cellulose organization appears to also impact digestibility of host PCWs, as reflected by differences in cellulose microfibril organization in woody and herbaceous PCWs and variation in cellulose-binding domain organization in cellulases of pathogenic fungi, which is known to influence enzyme access to cellulose. Taken together, this study highlighted the importance of chemical structure of both hemicelluloses and cellulose in host PCW digestibility by fungal pathogens.

【 授权许可】

Unknown