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14 | NewScientist | 11 August 2012 WATER, water everywhere – but at least one protein can function without the wet stuff. Martin Weik of the Institute for Structural Biology in Grenoble, France, and colleagues swapped the coating of water on myoglobin proteins – which normally carry oxygen to muscle – with a synthetic polymer that acts as a surfactant, effectively turning the proteins into a viscous liquid with a treacly consistency. Then they used a neutron scattering technique to observe how well the proteins could move, a measure of their proper functioning. They found that the protein- polymer hybrids moved as well as proteins in water. Importantly, they could still bind oxygen as well as myoglobin does in living tissue (Journal of the American Chemical Hot salmon delay having sex GLOBAL warming may be putting a freeze on Atlantic salmon sex. Fishing records from anglers on 59 Norwegian rivers show that more and more salmon are staying out at sea for two or more winters – instead of one – before migrating back upriver to mate. The trend, spotted by Leif Asbjørn Vøllestad of the University of Oslo and colleagues, coincides with warming in the North Atlantic between 1991 and 2005 (Ecology and Evolution, DOI: 10.1002/ece3.337). Salmon need to eat enough in the autumn for their gonads to mature the following spring. Temperature-driven changes in the food web mean fish may lack food at this critical time, forcing them to fatten up for longer before reproducing. Vøllestad says more time in predator-rich open waters may help explain their overall decline. On the upside, fish should be bigger when they swim upriver. Grizzlies are not bearing up well to food shortages SALMON shortages on Canada’s west coast may leave grizzlies there more stressed than the average bear. Heather Bryan at the University of Calgary in Alberta, Canada, working with the Raincoast Conservation Foundation in British Columbia, collected hair from grizzly and black bears across a 5000-square-kilometre area of British Columbia between 2009 and 2011. She looked for correlations between diet and hormone levels through DNA analysis, stable isotope analysis, and by quantifying hormone levels in the hair. Male grizzly bears that depend on having salmon in IAN MCALLISTER/ALL CANADA PHOTOS/GETTY IN BRIEF Water – it’s not all it’s cracked up to be Society, DOI: 10.1021/ja303894g). The find overturns the dogma that water is the most important biological molecule. “There are ways to replace water with something else and still keep proteins happy,” says Weik. An obvious question this raises is whether protein-based life might be able to exist in waterless environments – but this type of protein wouldn’t occur naturally since the polymer used is unlike any found in nature. their diet had higher levels of the stress hormone cortisol when they ate less fish. Studies in other mammals suggest that chronically high cortisol levels may suppress the immune system, leaving animals vulnerable to disease. Coastal grizzlies also had higher levels of testosterone than their non-salmon-eating relatives in the interior. “That might be related to social interaction,” says Bryan. “Since there are more bears on the coast, they have a higher population density and potentially more competition over limited resources like salmon.” Further monitoring should help predict how the coastal grizzlies will respond to environmental change, since many acquire 80 to 90 per cent of their dietary protein from salmon. Bryan presented her results at the Ecological Society of America meeting in Portland, Oregon, this week. A WOMAN with two missing fingers has grown them back – albeit as part of a phantom limb. The woman was born missing two fingers on her right hand. Aged 18, she had the hand amputated after a car accident. She later began to feel that her missing limb was still present, and that the phantom hand had short versions of the missing fingers. Paul McGeoch and colleagues at the University of California, San Diego, slowly trained her to feel that all five phantom digits were full size (Neurocase, DOI: 10.1080/13554794.2011.556128). “The deformed hand was suppressing the brain’s innate representation of her fingers,” he says. The innate representation kicked in again after the accident. Missing fingers grow as phantoms
