WIKIMEDIA, GRAHAM BEARDSIn the face of repeated exposure to ampicillin, populations of Escherichia coli quickly evolve tolerance for the drug, springing back to life once antibiotic treatment has stopped, according to a study published in Nature this week (June 25). Researchers from The Hebrew University of Jerusalem in Israel repeatedly exposed cultures of E. coli to high concentrations of ampicillin. Within as few as 10 cycles, the team found that some bacteria had survived the antibiotic treatments by lengthening the period of time they stay dormant.
“So far we’ve been familiar with tolerance conferred by dormant persister cells. This is a new phenomenon, extended lag, where mutants have a longer lag time, and that extended lag allows them to survive an attack by antibiotics,” said microbiologist Kim Lewis, director of the Antimicrobial Discovery Center at Northeastern University in Boston, who was not involved in the study.
PIXABAY, VIELEINERHUELLEWood-decaying fungi have long been classified by whether they degrade just cellulose or both lignin and cellulose, but a study of fungal genomes published in PNAS this week (June 23) suggests that classifying such species might not be so brown-and-white. In its paper, a team of investigators from the US Department of Energy’s Joint Genome Institute suggested there may exist “a continuum rather than a dichotomy between the white-rot and brown-rot modes of wood decay.”
“There was a lot of suspicion within the scientific community that the decay mechanisms wouldn’t be as straightforward as they’re currently classified, but the data wasn’t quite there,” said Dan Eastwood, a fungal biologist at Swansea University in Wales, who ...
