Widespread occurrence of expressed fungal secretory peroxidases in forest soils.
Fungal secretory peroxidases mediate fundamental ecological functions in the conversion and degradation of plant biomass. Many of these enzymes have strong oxidizing activities towards aromatic compounds and are involved in the degradation of plant cell wall (lignin) and humus. They comprise three major groups: class II peroxidases (including lignin peroxidase, manganese peroxidase, versatile peroxidase and generic peroxidase), dye-decolorizing peroxidases, and heme-thiolate peroxidases (e.g. unspecific/aromatic peroxygenase, chloroperoxidase). Here, we have repeatedly observed a widespread expression of all major peroxidase groups in leaf and needle litter across a range of forest ecosystems (e.g. Fagus, Picea, Acer, Quercus, and Populus spp.), which are widespread in Europe and North America. Manganese peroxidases and unspecific peroxygenases were found expressed in all nine investigated forest sites, and dye-decolorizing peroxidases were observed in five of the nine sites, thereby indicating biological significance of these enzymes for fungal physiology and ecosystem processes. Transcripts of selected secretory peroxidase genes were also analyzed in pure cultures of several litter-decomposing species and other fungi. Using this information, we were able to match, in environmental litter samples, two manganese peroxidase sequences to Mycena galopus and Mycena epipterygia and one unspecific peroxygenase transcript to Mycena galopus, suggesting an important role of this litter- and coarse woody debris-dwelling genus in the disintegration and transformation of litter aromatics and organic matter formation.
Department of Bio- and Environmental Sciences, International Institute Zittau, Technische Universität Dresden, Zittau, Germany.
Harald
H
Kellner
Ecologie Microbienne, UMR CNRS 5557, USC INRA 1364, Université de Lyon, Université Lyon 1, Villeurbanne, France.
Patricia
P
Luis
Department of Bio- and Environmental Sciences, International Institute Zittau, Technische Universität Dresden, Zittau, Germany.
Marek J
MJ
Pecyna
Ecologie Microbienne, UMR CNRS 5557, USC INRA 1364, Université de Lyon, Université Lyon 1, Villeurbanne, France.
Florian
F
Barbi
Department of Bio- and Environmental Sciences, International Institute Zittau, Technische Universität Dresden, Zittau, Germany; Department of Soil Ecology, UFZ - Helmholtz Center for Environmental Research, Halle/Saale, Germany.
Danuta
D
Kapturska
Department of Soil Ecology, UFZ - Helmholtz Center for Environmental Research, Halle/Saale, Germany.
Dirk
D
Krüger
School of Natural Resources and Environment, University of Michigan, Ann Arbor, Michigan, United States of America.
Donald R
DR
Zak
Ecologie Microbienne, UMR CNRS 5557, USC INRA 1364, Université de Lyon, Université Lyon 1, Villeurbanne, France.
Roland
R
Marmeisse
Unité de Microbiologie et Génomique, Gembloux Agro-Bio Tech, Université de Liège, Gembloux, Belgium.
Micheline
M
Vandenbol
Department of Bio- and Environmental Sciences, International Institute Zittau, Technische Universität Dresden, Zittau, Germany.
Martin
M
Hofrichter
D000595:Amino Acid Sequence; D001487:Basidiomycota / Q000201:enzymology*; D065928:Forests; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
D005656:Fungal Proteins; D010544:Peroxidases; C042858:lignin peroxidase; C051129:manganese peroxidase