Anaerobic fungi, which die in the presence of oxygen, thrive in herbivore guts and help them digest their host’s last leafy meal. In their evolutionary history, these fungi branched off early from aerobic fungi, which can breathe oxygen — just like we do. Oxygen is a rich source of energy, and because anaerobic fungi can’t harness it, scientists long held that these fungi don’t have the energy to make complex compounds called natural products. Yet, analyzing the genomes and genome products of four anaerobic fungal species has revealed that this group is unexpectedly powerful: they can whip up dozens of complex natural products, including new ones. The work was partly enabled by the “Facilities Integrating Collaborations for User Science” (FICUS) collaborative science initiative between the JGI and the Environmental Molecular Sciences Laboratory. Read the full science highlight on the JGI website.
Fungi, particularly those found in the digestive tracts of ruminant herbivores such as cattle, sheep, and goats, are very good at overcoming the resistance of plant cell walls to degradation—a major hurdle in the quest to produce sustainable fuels and chemicals from bioenergy feedstocks. Now, an international group of researchers has identified protein scaffolds in anaerobic gut fungi that provide docking sites for various enzymes, keeping them in place so that they can work together more effectively. As reported in the May 26 issue of Nature Microbiology, the structures are analogous to cellulosome complexes in anerobic bacteria, but this is the first time they have been found in fungi.
Just four letters – A, C, T, and G – make up an organism’s genetic code. Changing a single letter, or base, can lead to changes in protein structures and functions, impacting an organism’s traits. In addition, though, subtler changes can and do happen, involving modifications of the DNA bases themselves. In the May 8, 2017 issue of Nature Genetics, a team led by scientists at the U.S. Department of Energy Joint Genome Institute (JGI), a DOE Office of Science User Facility, report the prevalence of modifications in the earliest branches of the fungal kingdom. Read more in the JGI press release.