In a paper published online in advance this week, researchers at the University of Washington and Harvard University introduce a metagenomic systems biology computational framework, through which they've identified topological shifts in the human gut microbiome associated with obesity and inflammatory bowel disease. "The system-level approach presented here lays the foundation for a unique framework for studying the human microbiome, its organization, and its impact on human health," the authors write.
An international team led by investigators at Germany's Jacobs University Bremen shows that, in E. coli, "gene order and chromosome dynamics coordinate spatiotemporal gene expression during the bacterial growth cycle." The team says its analysis provides "mechanistic insight into how the organization of a complete bacterial chromosome encodes a spatiotemporal program integrating DNA replication and global gene expression."
Elsewhere in this week's PNAS Early Edition, investigators at the University of Montana show in a multigenerational pedigree analysis involving wild-born and first-generation hatchery fish that "genetic adaptation to captivity can occur in a single generation." The researchers found that the hatchery fish "had nearly double the lifetime reproductive success ... when spawned in captivity compared with wild fish spawned under identical conditions," they report.