Available online at www.sciencedirect.com Enzyme and Microbial Technology 43 (2008) 186–192 Activity and spatial distribution of lignocellulose-degrading enzymes during forest soil colonization by saprotrophic basidiomycetes Jaroslav ˇ Snajdr, Vendula Val´ aˇ skov´ a, Vˇ era Merhautov´ a, Tom´ aˇ s Cajthaml, Petr Baldrian ∗ Division of Ecology, Institute of Microbiology of the ASCR v.v.i., V´ ıdeˇ nsk´ a 1083, 14220 Prague 4, Czech Republic Received 8 July 2007; received in revised form 15 October 2007; accepted 14 November 2007 Abstract Activity and production of extracellular enzymes by saprotrophic litter-decomposing basidiomycetes Hypholoma fasciculare and Rhodocollybia butyracea was studied in microcosms with reconstructed L, O and Ah horizons of a soil profile of Quercus petraea forest soil. Both H. fasciculare and R. butyracea colonized the L layer of microcosms rapidly, while the colonization of O layer was slower. The Ah layer was substantially colonized only by R. butyracea. Enzyme activities in the soil microcosms decreased from the L layer > O layer > Ah layer and activities in microcosms inoculated with the fungi were quite similar to each other. Compared to control, the most apparent was the increase of ligninolytic enzyme activities. Laccase activities in H. fasciculare and R. butyracea-colonized L layers were 3-fold compared to control and the activity maxima of Mn- peroxidase in fungus-colonized O layers were 2–3-fold and in the L layers up to 40-fold compared to controls. Activities of cellulolytic enzymes, chitinase and acidic phosphatase in both fungal treatments were higher in the L layer on weeks 2–6 while the activity of alkaline phosphatase did not show differences between fungus-colonized and control treatments. Both fungi decreased fungal CFU in the L layer but significantly increased the counts in the O layer. Both fungi also increased bacterial CFU in the O layer, R. butyracea more than H. fasciculare. The analysis of fungal and bacterial biomass based on ergosterol content and PLFA analysis showed a sharp decrease from L to Ah layer, but did not show significant differences among treatments. © 2007 Elsevier Inc. All rights reserved. Keywords: Lignocellulose; Soil; Litter; Saprotrophic basidiomycetes; Laccase; Mn-peroxidase 1. Introduction In temperate broadleaved forests, litter constitutes the major source of organic matter entering the soil environment. There are three major macromolecular components of litter, namely the polysaccharides cellulose and hemicellulose and the aro- matic polymer lignin, the latter being considered as the most recalcitrant. Lignocellulose degrading enzymes found in forest litter and soil include both the cellulolytic [1] and ligninolytic ones [2–4] and their production sometimes reflects the presence of fungal mycelia or fruit bodies [5]. Activities of ligninolytic enzymes in the upper layers of the hardwood forest soil can exhibit a high spatial variability. The activities of laccase and ∗ Corresponding author at: Laboratory of Biochemistry of Wood-Rotting Fungi, Institute of Microbiology of the ASCR v.v.i., V´ ıdeˇ nsk´ a 1083, 14220 Praha 4, Czech Republic. Tel.: +420 241062315; fax: +420 241062384. E-mail address: baldrian@biomed.cas.cz (P. Baldrian). Mn-peroxidase in the Quercus petraea forest were found to span almost three orders of magnitude in the uppermost L and O horizons [4,6]. In general, it is assumed that by far the greatest part of lig- nocellulose degradation in soils is performed by fungi and litter decomposition in temperate forests is mainly driven by fungal activity [7,8]. Litter-decomposing basidiomycetes (LDF) are the only known efficient producers of ligninolytic enzymes laccase and Mn-peroxidase [9,10], but LDF also produce hydrolytic enzymes degrading cellulose, hemicelluloses and chitin [11]. The aim of this work was to find how the presence of litter- decomposing basidiomycetes affects enzyme activities in the forest soil environment. For this purpose, we used two litter- decomposing fungi, Hypholoma fasciculare and Rhodocollybia butyracea, that were previously demonstrated to efficiently degrade oak litter and to produce the lignocellulose-degrading enzymes laccase, Mn-peroxidase, endo-1,4--glucanase, 1,4- -glucosidase and cellobiohydrolase [12]. The fungi were 0141-0229/$ – see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.enzmictec.2007.11.008