Faculty of Science and Technology, Free University of Bolzano/Bozen, Bolzano/Bozen, Italy.
Institute of Research on Terrestrial Ecosystems (IRET), National Research Council (CNR), Monterotondo Scalo (RM), Italy.
Environ Microbiol. 2023 Nov;25(11):2351-2367. doi: 10.1111/1462-2920.16459. Epub 2023 Jul 5.
We investigated the changes in microbial community diversities and functions in natural downed wood at different decay stages in a natural oak forest in the Italian Alps, through metagenomics analysis and in vitro analysis. Alfa diversity of bacterial communities was affected by the decay stage and log characteristics, while beta diversity was mainly driven by log diameter. Fungal and archaeal beta diversities were affected by the size of the sampled wood (log diameter), although, fungi were prominently driven by wood decay stage. The analysis of genes targeting cell wall degradation revealed higher abundances of cellulose and pectin-degrading enzymes in bacteria, while in fungi the enzymes targeting cellulose and hemicellulose were more abundant. The decay class affected the abundance of single enzymes, revealing a shift in complex hydrocarbons degradation pathways along the decay process. Moreover, we found that the genes related to Coenzyme M biosynthesis to be the most abundant especially at early stages of wood decomposition while the overall methanogenesis did not seem to be influenced by the decay stage. Intra- and inter-kingdom interactions between bacteria and fungi revealed complex pattern of community structure in response to decay stage possibly reflecting both direct and indirect interactions.
我们通过宏基因组分析和体外分析，研究了意大利阿尔卑斯山天然橡树林中不同腐朽阶段天然倒下木材中微生物群落多样性和功能的变化。细菌群落的α多样性受到腐朽阶段和原木特征的影响，而β多样性主要由原木直径驱动。真菌和古菌的β多样性受到采样木材大小（原木直径）的影响，尽管真菌主要受木材腐朽阶段的驱动。针对细胞壁降解的基因分析表明，细菌中纤维素和果胶降解酶的丰度较高，而真菌中针对纤维素和半纤维素的酶的丰度较高。腐朽等级影响单个酶的丰度，揭示了在腐朽过程中复杂碳氢化合物降解途径的转变。此外，我们发现与辅酶 M 生物合成相关的基因特别在木材分解的早期阶段最为丰富，而整体产甲烷作用似乎不受腐朽阶段的影响。细菌和真菌之间的种内和种间相互作用揭示了群落结构的复杂模式，这可能反映了直接和间接的相互作用。
