Folman Larissa B, Klein Gunnewiek Paulien J A, Boddy Lynne, de Boer Wietse
Department of Plant Microorganism Interactions, NIOO-Centre for Terrestrial Ecology, ZG Heteren, The Netherlands.
FEMS Microbiol Ecol. 2008 Feb;63(2):181-91. doi: 10.1111/j.1574-6941.2007.00425.x.
White-rot fungi are important wood-decomposing organisms in forest ecosystems. Their ability to colonize and decompose woody resources may be strongly influenced by wood-inhabiting bacteria that grow on easily utilizable compounds e.g. oligomers of wood-polymers released by fungal enzymes. However, so far, it is not known how white-rot fungi deal with the presence of potential competing bacteria. Here, the effects of two white-rot fungi, Hypholoma fasciculare and Resinicium bicolor, on the numbers and composition of bacteria colonizing sterile beech wood blocks from forest soil are reported. Both total numbers (microscopic counts) and the numbers of cultivable wood-inhabiting bacteria were considerably lower in wood blocks that became colonized by the white-rot fungi than in control blocks. This points to the fungi out-competing the opportunistic bacteria. The presence of white-rot fungi resulted in a change in the relative abundance of families of cultivable bacteria in wood and also in a change of denaturing gradient gel electrophoresis patterns of directly amplified 16S rRNA gene fragments. Analysis of the bacterial community structure in soil adhering to exploratory mycelium (cords) indicated that fungal species-specific effects on bacterial community composition were also apparent in this fungal growth phase.
白腐真菌是森林生态系统中重要的木材分解生物。它们在木质资源上定殖和分解的能力可能会受到生长在易利用化合物（如真菌酶释放的木材聚合物低聚物）上的木材栖居细菌的强烈影响。然而，到目前为止，尚不清楚白腐真菌如何应对潜在竞争细菌的存在。在此，报道了两种白腐真菌——簇生垂幕菇（Hypholoma fasciculare）和双色蜡伞（Resinicium bicolor）对来自森林土壤的无菌山毛榉木块上定殖细菌数量和组成的影响。与对照木块相比，被白腐真菌定殖的木块中细菌总数（显微镜计数）和可培养的木材栖居细菌数量均显著更低。这表明真菌在与机会主义细菌的竞争中胜出。白腐真菌的存在导致木材中可培养细菌家族的相对丰度发生变化，同时也导致直接扩增的16S rRNA基因片段的变性梯度凝胶电泳图谱发生变化。对附着在探索性菌丝体（菌索）上的土壤中细菌群落结构的分析表明，在这个真菌生长阶段，真菌物种对细菌群落组成的特异性影响也很明显。
