In Nature this week, a Cold Spring Harbor Laboratory-led team publishes an improved maize reference genome, which was assembled and annotated using single-molecule real-time sequencing and high-resolution optical mapping. Relative to the previous reference genome, the new assembly features a 52-fold increase in contig length, as well as significant improvements in the assembly of intergenic spaces and centromeres. The work demonstrates that high-quality assemblies of other repeat-rich and large-genome plants is feasible and can "extend our understanding of the genetic diversity that forms the basis of the phenotypic diversity in … economically important plants," the authors write.
And in Nature Biotechnology, a multi-institute group of researchers reports on 1,003 reference genomes sequenced as part of the Genome Encyclopedia of Bacteria and Archaea initiative. The genomes double the number of existing type strains and expand their overall phylogenetic diversity by 25 percent, while comparative analyses with previously available finished and draft genomes reveal a 10.5 percent increase in novel protein families as a function of phylogenetic diversity. The new resource, the authors note, marks the largest single release of reference genomes to date, although they note that the "bacterial and archaeal isolate sequence space is still far from saturated." GenomeWeb has more on this study, here.