FLICKR, JOSIAH MACKENZIEThe team that first identified irisin—a fat-browning protein commonly called “the exercise hormone”—has again provided evidence that it circulates in human blood and is released following physical activity. In a Cell Metabolism paper published this week (August 13), Harvard Medical School’s Bruce Spiegelman and his colleagues used tandem mass spectrometry to show that irisin—the subject of much debate this year—exists.
“There is no next level of analysis,” Spiegelman told The Scientist. “This is down to, literally, the atomic level.”
“Using state-of-the-art mass spectrometry, the authors show irisin in circulation—the strongest evidence for irisin in humans,” said Sven Enerbäck of Gothenburg University in Sweden who was not involved in the work. “The field can now turn to evaluating the effects of irisin on human physiology.”
STEPHANIE GALANIEStanford University’s Christina Smolke and her colleagues have fully re-engineered the biosynthetic pathway that turns a sugar into an opioid precursor in the yeast Saccharomyces cerevisiae. Their results were published in Science this week (August 13).
“It’s the first time an entire pathway from sugar to morphinans has been stitched together,” said Ian Graham, a geneticist at the University of York, U.K., who was not involved in the study.
To create its ...
