It’s a tough job, but someone’s got to do it. In this case, the “job” is the breakdown of lignin, the structural molecule that gives plants strength and rigidity. One of the most abundant terrestrial polymers (large molecules made of repeating subunits called monomers) on Earth, lignin surrounds valuable plant fibers and other molecules that could be converted into biofuels and other commodity chemicals – if we could only get past that rigid plant cell wall.
These fungi are part of the genus Lentinula, which have evolved to decompose hardwoods on every continent besides Europe and Antarctica. Lentinula mushrooms are white rot fungi, belonging to an elite group of decomposers that can break down all of wood’s components — cellulose, hemicellulose, and the toughest molecule, lignin. Understanding Lentinula genomes and their evolution could provide strategies for converting plant waste into sugars for biofuel production.
As part of an international team, researchers at the Joint Genome Institute (JGI) helped sequence and analyze the genomes of four fungi of the genus Armillaria. Often called the humongous fungus, Armillaria form some of the planet’s largest living organisms. They are also among the most devastating fungal pathogens, capable of breaking down all of the components of a host plant’s cell walls.