In this week's Science, researchers from Lawrence Berkeley National Laboratory and collaborators describe the reconstruction of the nearly complete genomes of 21 bacteria that have been widely detected in anaerobic environments, but whose metabolisms remained unclear. The investigators delivered acetate to an aquifer to stimulate the bacteria, then filtered out microbial cells. Of the 49 distinct genomes detected, they were able to mostly complete 21 genomes. None of the organisms appear to require oxygen, and they may play "previously unrecognized roles in hydrogen production, sulfur cycling, and fermentation of refractory sedimentary carbon."
Elsewhere in Science, an international team led by INSERM researchers uncover new details on a system by which cancer cells with an abnormal number of chromosomes are detected and destroyed. According to the report, hyperploid cancer cells stress the endoplasmic reticulum, causing the aberrant cell surface exposure of the protein calreticulin. This, in turn, triggers an immune response that eliminates the cancer cell. The findings "unveil an immunosurveillance system that imposes immunoselection against hyperploidy in carcinogen- and oncogene-induced cancers."
Meanwhile, in Science Translational Medicine, Stanford University Medical School investigators publish a study showing that cystic fibrosis patients carry a distinct set of microbial communities in their lungs that are not present in healthy individuals. Using high-throughput sequencing, the team discovered "diverse microbial communities in the healthy samples, contravening conventional wisdom that healthy airways are not significantly colonized." Comparing these communities to those in cystic fibrosis patients "revealed significant differences in microbial ecology, including differential representation of uncultivated phylotypes." A comparison of the sequencing results with clinical data showed that diminished microbial activity is associated with the severity of lung inflammation in patients, as well.