In a paper appearing in this week's PNAS Early Edition, researchers at Cornell University "present a proof-of-principle demonstration for a new method using a nanofluidic device that combines real-time detection and automated sorting of individual molecules based on their epigenetic state." For this demonstration, the researchers report that their technology showed up to 98 percent accuracy in molecule sorting and that it "achieved postsorting sample recovery on femtogram quantities of genetic material." Overall, the Cornell team says that "the functionality enabled by this nanofluidic platform now provides a workflow for color-multiplexed detection, sorting, and recovery of single molecules toward subsequent DNA sequencing."
Researchers at the University of Wisconsin-Madison, the Morgridge Institute for Research, also in Madison, and at the University of California, Santa Barbara, present inSeq — "a sequence identification algorithm that processes tandem mass spectra in real-time using the mass spectrometer's onboard processors."
Elsewhere in the Early Edition, an international team led by investigators at the University of Edinburgh presents a Bayesian phylogenetic reconstruction to trace the emergence, adaptation, and transmission of hospital-associated methicillin-resistant Staphylococcus aureus. Using genome sequences for 87 clinical S. aureus isolates collected across three continents during a 53-year period, the team found "striking molecular correlates of hospital- or community-associated pandemics represented by mobile genetic elements and non-synonymous mutations affecting antibiotic resistance and virulence."
In another PNAS advance online publication, researchers at the China Agricultural University, BGI-Shenzhen, and France's CNRS-Paul Sabatier University report on their comparative analysis of 26 genomes of Sinorhizobium and Bradyrhizobium nodulating soybean, in which they aim to decipher strategies that have contributed to varied rhizobium-legume symbiosis. "Surprisingly, no genes are specifically shared by these soybean microsymbionts compared with other legume microsymbionts," the authors write. "On the other hand, phyletic patterns of 561 known symbiosis genes of rhizobia reflected the species phylogeny of these soybean microsymbionts and other rhizobia."