Laboratory of Environmental Microbiology, Institute of Microbiology of the ASCR, v.v.i., Vídeňská 1083, 14220, Praha 4, Czech Republic.
Biodegradation. 2011 Jul;22(4):709-18. doi: 10.1007/s10532-010-9390-8. Epub 2010 Jul 29.
Saprotrophic wood-inhabiting basidiomycetes are the most important decomposers of lignin and cellulose in dead wood and as such they attracted considerable attention. The aims of this work were to quantify the activity and spatial distribution of extracellular enzymes in coarse wood colonised by the white-rot basidiomycete Fomes fomentarius and in adjacent fruitbodies of the fungus and to analyse the diversity of the fungal and bacterial community in a fungus-colonised wood and its potential effect on enzyme production by F. fomentarius. Fungus-colonised wood and fruitbodies were collected in low management intensity forests in the Czech Republic. There were significant differences in enzyme production by F. fomentarius between Betula pendula and Fagus sylvatica wood, the activity of cellulose and xylan-degrading enzymes was significantly higher in beech wood than in birch wood. Spatial analysis of a sample B. pendula log segment proved that F. fomentarius was the single fungal representative found in the log. There was a high level of spatial variability in the amount of fungal biomass detected, but no effects on enzyme activities were observed. Samples from the fruiting body showed high β-glucosidase and chitinase activities compared to wood samples. Significantly higher levels of xylanase and cellobiohydrolase were found in samples located near the fruitbody (proximal), and higher laccase and Mn-peroxidase activities were found in the distal ones. The microbial community in wood was dominated by the fungus (fungal to bacterial DNA ratio of 62-111). Bacterial abundance composition was lower in proximal than distal parts of wood by a factor of 24. These results show a significant level of spatial heterogeneity in coarse wood. One of the explanations may be the successive colonization of wood by the fungus: due to differential enzyme production, the rates of biodegradation of coarse wood are also spatially inhomogeneous.
腐生木质层孔菌是分解木质素和纤维素的最重要的分解者，因此它们引起了相当多的关注。本研究的目的是量化白腐菌 Fomes fomentarius 定殖粗木质部以及相邻真菌子实体的胞外酶活性和空间分布，并分析定殖木质部的真菌和细菌群落的多样性及其对 F. fomentarius 酶产生的潜在影响。真菌定殖的木材和子实体是在捷克共和国低管理强度森林中收集的。在山毛榉木和欧洲山毛榉木中，F. fomentarius 的酶产生存在显著差异，纤维素和木聚糖降解酶的活性在山毛榉木中显著高于山毛榉木。对一段山毛榉原木样本的空间分析证明，F. fomentarius 是原木中唯一发现的真菌代表。真菌生物量的检测量存在很高的空间变异性，但没有观察到对酶活性的影响。与木材样本相比，子实体样本显示出较高的β-葡萄糖苷酶和几丁质酶活性。在靠近子实体（近端）的样本中发现了更高水平的木聚糖酶和纤维二糖水解酶，而在远离子实体（远端）的样本中发现了更高水平的漆酶和锰过氧化物酶。木材中的微生物群落主要由真菌（真菌与细菌 DNA 比为 62-111）组成。近端的细菌丰度组成比远端低 24 倍。这些结果表明粗木质部具有显著的空间异质性。原因之一可能是真菌对木材的连续定殖：由于酶产量的差异，粗木质部的生物降解速率在空间上也是不均匀的。
