Within the framework of the CSP 'Metatranscriptomics of Forest Soil Ecosystems' project, we are aiming to explore the interaction of forest trees with communities of soil fungi, including ectomycorrhizal symbionts that dramatically affect bioenergy-relevant plant growth, and saprotrophic soil fungi impacting carbon sequestration in forests. We are sequencing the genome of the most abundant fungal species harvested on studied sites to serve as the foundation for a reference database for metagenomics of fungi and for a comprehensive survey of the potential soil fungal metabolome.
Laetiporus sulphureus
This species belongs to the Polyporales, where it represents an enigmatic lineage of brown-rot fungi (which degrade the cellulose and hemicellulose components of wood, while leaving the recalcitrant lignin fraction behind). In addition to brown-rot, it has been suggested that members of the genus Laetiporus can also live parasitically on many wood species. It grows on various hardwood species and forms spectacular yellow bracketed fruiting bodies, which can reach a weight of several kilograms. It is also called the chicken of the woods and is a popular edible mushroom all over Europe and North America. It can also be cultivated for commercial distribution. The impressive size of its fruiting bodies suggests that L. sulphureus has a successful enzymatic apparatus for brown-rot.
The evolution of brown-rot from white-rot ancestors has been investigated recently, revealing several common features, such as extensive loss of lignin-degrading enzyme families (Floudas et al 2012, Science. 336(6089):1715-1719.). However, several aspects of the evolution of nutritional modes remained obscure. By adding Laetiporus to the suite of Polyporales species for which complete genome sequences are available, we expect to obtain a fine-scale picture on the evolution of the wood-decay enzymatic apparatus in these fungi. Analysis of a broad sample of polypores will provide a comprehensive picture on the fate of decay-related gene families and will enable us to make inferences about the function of these gene families.
Genome Reference(s)
Nagy LG, Riley R, Tritt A, Adam C, Daum C, Floudas D, Sun H, Yadav JS, Pangilinan J, Larsson KH, Matsuura K, Barry K, Labutti K, Kuo R, Ohm RA, Bhattacharya SS, Shirouzu T, Yoshinaga Y, Martin FM, Grigoriev IV, Hibbett DS
Comparative Genomics of Early-Diverging Mushroom-Forming Fungi Provides Insights into the Origins of Lignocellulose Decay Capabilities.
Mol Biol Evol. 2016 Apr;33(4):959-70. doi: 10.1093/molbev/msv337