Title
Comparative analysis of secretome profiles of manganese(II)-oxidizing Ascomycete fungi
Department/School
Biology
Date
2016
Document Type
Article
Keywords
fungi, fungal genomics, proteases, Ascomycetes, plant fungal pathogens, genome analysis, glycoside hydrolases, Basidiomycetes
DOI
DOI: 10.1371/journal.pone.0157844
Abstract
Fungal secretomes contain a wide range of hydrolytic and oxidative enzymes, including cellulases, hemicellulases, pectinases, and lignin-degrading accessory enzymes, that synergistically drive litter decomposition in the environment. While secretome studies of model organisms such as Phanerochaete chrysosporium and Aspergillus species have greatly expanded our knowledge of these enzymes, few have extended secretome characterization to environmental isolates or conducted side-by-side comparisons of diverse species. Thus, the mechanisms of carbon degradation by many ubiquitous soil fungi remain poorly understood. Here we use a combination of LC-MS/MS, genomic, and bioinformatic analyses to characterize and compare the protein composition of the secretomes of four recently isolated, cosmopolitan, Mn(II)-oxidizing Ascomycetes (Alternaria alternata SRC1lrK2f, Stagonospora sp. SRC1lsM3a, Pyrenochaeta sp. DS3sAY3a, and Paraconiothyrium sporulosum AP3s5-JAC2a). We demonstrate that the organisms produce a rich yet functionally similar suite of extracellular enzymes, with species-specific differences in secretome composition arising from unique amino acid sequences rather than overall protein function. Furthermore, we identify not only a wide range of carbohydrate-active enzymes that can directly oxidize recalcitrant carbon, but also an impressive suite of redox-active accessory enzymes that suggests a role for Fenton-based hydroxyl radical formation in indirect, non-specific lignocellulose attack. Our findings highlight the diverse oxidative capacity of these environmental isolates and enhance our understanding of the role of filamentous Ascomycetes in carbon turnover in the environment.
Volume
11
Issue
7
Published in
PLOS ONE
Citation/Other Information
Zeiner CA, Purvine SO, Zink EM, Paša-Tolic L, Chaput DL, Haridas S, Wu S, LaButti K, Grigoriev IV, Henrissat B, Santelli CM, Hansel CM. 2016. Comparative analysis of secretome profiles of manganese(II)-oxidizing Ascomycete fungi. PLoS ONE 11.7: e0157844. DOI: 10.1371/ journal.pone.0157844.