真菌的进化和煤炭积累的停止

The Paleozoic Origin of Enzymatic Lignin Decomposition Reconstructed from 31 Fungal Genomes

The research suggested that fungi evolved to break down lignin, which keeps plant cell walls rigid. Because this could break lignin down completely, it no longer accumulated as peat, the source material for the formation of coal. The researchers sequenced the genomes of 31 species of Basidiomycetes, which includes brown rotfungi that breaks down the cellulose in construction timber and white rot fungi thatbreaks down both lignin and cellulose. They searched for gene families for class IIfungal peroxidases, enzymes that are present in the lineages of white rot fungi butnot in brown rot fungi, suggesting they play a role in breaking down lignin.

The researchers could track the evolution of the enzymes back through the fungallineage, based on the fact that genes accumulate mutations at a roughly constantrate. This suggested that a white rot fungal ancestor appeared at the end of theCarboniferous period, around 290 million years ago, that was able to break downlignin. This paper, published in Science, will be the first chapter in the Genomic Encyclopedia of Fungi,