Sylvan Biosciences, 198 Nolte Drive, Kittanning, PA 16201, USA.
Fungal Genet Biol. 2013 Jun;55:2-5. doi: 10.1016/j.fgb.2013.03.002. Epub 2013 Apr 2.
The genomes of two isolates of Agaricus bisporus have been sequenced recently. This soil-inhabiting fungus has a wide geographical distribution in nature and it is also cultivated in an industrialized indoor process ($4.7bn annual worldwide value) to produce edible mushrooms. Previously this lignocellulosic fungus has resisted precise econutritional classification, i.e. into white- or brown-rot decomposers. The generation of the genome sequence and transcriptomic analyses has revealed a new classification, 'humicolous', for species adapted to grow in humic-rich, partially decomposed leaf material. The Agaricus biporus genomes contain a collection of polysaccharide and lignin-degrading genes and more interestingly an expanded number of genes (relative to other lignocellulosic fungi) that enhance degradation of lignin derivatives, i.e. heme-thiolate peroxidases and β-etherases. A motif that is hypothesized to be a promoter element in the humicolous adaptation suite is present in a large number of genes specifically up-regulated when the mycelium is grown on humic-rich substrate. The genome sequence of A. bisporus offers a platform to explore fungal biology in carbon-rich soil environments and terrestrial cycling of carbon, nitrogen, phosphorus and potassium.
最近，两株双孢蘑菇（Agaricus bisporus）的基因组已被测序。这种土壤栖息真菌在自然界中分布广泛，也在工业化的室内过程中进行栽培（全球每年价值 47 亿美元）以生产可食用蘑菇。此前，这种木质纤维素真菌一直难以进行精确的生态营养分类，即归入白腐菌或褐腐菌。基因组序列和转录组分析的结果揭示了一种新的分类，即“腐生菌”，适用于在富含腐殖质、部分分解的叶材料中生长的物种。双孢蘑菇的基因组包含了一系列多糖和木质素降解基因，更有趣的是，与其他木质纤维素真菌相比，它扩展了许多能够增强木质素衍生物降解的基因，如血红素硫醇过氧化物酶和β-醚酶。在腐生菌适应套件中，一个假定的启动子元件存在于大量基因中，当菌丝在富含腐殖质的基质上生长时，这些基因被特异性地上调。双孢蘑菇的基因组序列为探索富碳土壤环境中的真菌生物学以及碳、氮、磷和钾的陆地循环提供了一个平台。
