Louise Glass (right) with graduate student Anna Simonin

N. Louise Glass:

Studying the ‘Little Aliens’

An unassuming fungus, originally isolated as an orange bread mold in French bakeries, might be an unlikely superhero in the quest to find the pathway to sustainable cellulosic biofuels. UC Berkeley Professor Louise Glass, who through decades of work on the fungus Neurospora crassa has become a world authority on how fungi interact with other organisms in nature, thinks that studying Neurospora could hold the key to understanding how cellulose and lignin degrade in plant cell walls.

 Glass says her introduction to these fascinating creatures – she says they are like “little aliens” – led her to a distinguished career in mycology. Neurospora, the focus of her EBI program, is the classic model organism, simple to grow and widely studied, with a sequenced genome and many community tools and resources.  Neurospora was the feature organism for the Nobel Prize-winning “one gene-one enzyme” hypothesis. Work on the fungus continues today on many different topics, including cell fusion, circadian rhythms, development, evolution, and gene silencing mechanisms.

Glass and her colleagues, principal investigators John Taylor and Tom Bruns, might be called the model organism for the EBI, which prides itself on cross-discipline collaborations. The three form a well-rounded team - – Glass the molecular biologist, Bruns the ecologist, and Taylor the population geneticist. They talked one day at a weekly floor tea about how the ability of fungi to decay grasses might be used for biofuel production. So they integrated their expertise in an effort to optimize fungi, like Neurospora, to decay Miscanthus grass, a necessary step in converting this plant into biofuel.

Many mutant strains of Neurospora have been developed in its long history, including some important for cell wall degradation. Figuring out how Neurospora regulates Miscanthus cell wall degradation is a painstaking process. The scientists get industrial-grade milled Miscanthus from the University of Illinois, then assess its utilization as a sole carbon source with wild and mutant Neurospora strains. The expression of every gene in the fungus is monitored, so that gene expression patterns can be correlated with Miscanthus degradation.  In a few years, it is hoped, bioengineers will be able to synthesize new fungal enzymes that are capable of more efficiently degrading plant cell walls.

“We will learn much about aspects of plant decay that are not understood,” Glass says. “It will give us a holistic view that we haven’t known before, of the regulatory network of genes and proteins and enzymes that are required for the fungal degradation of cellulose and lignin.”