EGSB News

The last common ancestor of humans and rodents lived more than 80 million years ago, and billions of changes in their respective DNA sequences have occurred over this vast timespan. Yet, intriguingly, there are a few hundred stretches of DNA in our genome that are still identical to the corresponding sequences in mice and rats. Generally, sequence conservation between distantly related species is an indication that the function the DNA serves is vitally important and highly sensitive to mutations. For example, most DNA sequences that encode proteins show at least moderate conservation in evolution. However, more than two-thirds of the “ultraconserved” sequences shared by humans and rodents are outside of protein-coding genes, raising the question of what led to their extreme level of conservation.

Researchers in the Environmental Genomics and Systems Biology (EGSB) and Biological Systems and Engineering (BSE) Divisions at Berkeley Lab employed a large-scale functional genomics approach to systematically characterize Bacteroides thetaiotaomicron, a beneficial bacterium prevalent in the human gut. They performed hundreds of genome-wide fitness assays and identified new functions for 40 proteins, including antibiotic tolerance, polysaccharide degradation, and colonization of the GI tract in germ-free mice.

In PNAS, a research team led by Sabeeha Merchant at UC Berkeley has found numerous examples of polycistronic expression – in which two or more genes are encoded on a single molecule of mRNA – in two species of green algae. Go here to watch a video about the work.

Two Biosciences Area researchers—Natalia Ivanova and Susannah Tringe—are among 65 new Fellows elected into the American Academy of Microbiology’s 2021 class. An honorific leadership group within the American Society for Microbiology, the mission of the Academy is to provide microbiological expertise in the service of science and the public. Fellows are elected annually through a highly-selective peer-review process based on their records of scientific achievement and contributions in the field of microbiology.

Senior Scientist Susannah Tringe has been named Environmental Genomics and Systems Biology (EGSB) Division Director. Over her seventeen year career at Berkeley Lab, Tringe has become known as a leader in the field of metagenomics, and has influenced the careers of countless researchers around the world as the deputy of user programs at the DOE Joint Genome Institute (JGI). Tringe will continue to lead the Microbial Systems Group at the JGI and is the scientific lead for implementation of the EcoPOD prototype for EGSB, which is a new high-tech ecosystem chamber that can replicate interactions between organisms and environments in natural systems.