Skip to main content
Premium Trial:

Request an Annual Quote

This Week in PNAS: Mar 24, 2015

Editor's Note: Some of the articles described below are not yet available at the PNAS site, but they are scheduled to be posted some time this week.

In the early, online edition of the Proceedings of the National Academy of Sciences, researchers from the US and Germany used a combination of metagenomic sequencing and genome sequencing on individual isolates to characterize a free-living Trichodesmium erythraeum cyanobacteria strain known as IMS101. The bug, known for its ability to fix carbon and produce nitrogen, has a genome with robust non-protein coding content and relatively sparse protein-coding sequences. From the new analysis, the team showed that much of the non-coding sequence space is made up large swathes of intergenic sequence that are highly conserved, with roughly 86 percent of the non-coding sequencing being transcribed.

Investigators from Rockefeller University demonstrate the feasibility of identifying natural product pathways using a bioinformatics and multiplexed, metagenomic sequencing method that focuses on gene clusters corresponding to conserved motifs in a given natural product group. For their proof-of-principle study, the researchers used this method — dubbed "environmental surveyor of natural product diversity," or eSNaPD — to track down nearly 100 epoxyketone proteasome enzyme inhibitors in soil metagenome samples from 185 sites around the world.

Finally, a team from Switzerland, Germany, and Mexico used genome sequencing to characterize a recently discovered Mycobacterium species that is behind a form of leprosy known as diffuse lepromatous leprosy, or Lucio's leprosy. The researchers put together a de novo genome assembly for a Mycobacterium lepromatosis isolate obtained from a Mexican man's liver autopsy. Using this sequence and a draft genome generated for another patient isolate, they then did comparisons between M. lepromatosis and the better known M. leprae bug, which was long thought to be the only leprosy-causing agent. GenomeWeb has more on the study, here.