Ars Technica: How to reduce the amount of carbon dioxide pumped into the atmosphere has been one of the main scientific challenges facing humanity over the last 20 years. One potential solution is to recycle the CO2 into something more useful via a catalytic reaction. Using an enzyme that converts nitrogen gas (N2) to ammonia (NH3), Lance Seefeldt at Utah State University and his colleagues have developed the first biochemical process that mimics inorganic catalytic reactions. That catalytic process is similar to the conversion of CO2 into methane (CH4), so Seefeldt’s team engineered the enzyme to process CO2 instead of N2. Before slowing down, the engineered enzyme successfully converted CO2 for 20 minutes, a rate comparable to inorganic catalysis. Seefeldt’s team also discovered that the enzyme combined CO2 with acetylene (C2H2) to create propylene (C3H6), an ingredient in many plastics. This is the first known catalytic reaction, biological or inorganic, known to create propylene. The success of the enzymatic conversion provides a new method for recycling CO2 and opens new avenues of research in catalysis and bioengineering.
Daily Archives: November 21, 2012
Potential gamma-ray signal could be evidence of dark matter
Scientific American: In April, Christoph Weniger of the GRAPPA Institute in Amsterdam examined public data from the Fermi Gamma-ray Space Telescope’s primary instrument: the Large Area Telescope (LAT). He found evidence of a high-energy gamma-ray signal emanating from the galactic center. No known astronomical phenomenon could account for the signal and Weniger believed it could only have been caused by dark matter particle collisions. Now, the team members running the LAT have indicated that they, too, found a 135-GeV gamma-ray line coming from near the galactic core. However, Andrea Albert, one of the Fermi team members from the Ohio State University, says the signal only has a 3.35-sigma local significance. That means there is not yet definite evidence of a signal, and it could just be variation in the background or a data processing artifact. Albert also says that the team detected a similar, though even less significant, signal at the same energy level when the telescope looked at the outer rim of Earth’s atmosphere. If so, then both signals could be the result of some artifact of data collection or processing. Albert says that, within the next year, the team hopes to have enough evidence to determine whether the signal is real.
University in NY closes fracking institute
New York Times: Controversies over fracking—a method for extracting natural gas from rock—have led the University at Buffalo in New York to close its Shale Resources and Society Institute. University president Satish Tripathi cited several reasons for the decision to shut down the institute, including “that it lacked sufficient faculty presence, that it was not consistent enough in disclosing its financial interests and that the credibility of its research was compromised because of questions over its financing,” writes Mireya Navarro for the New York Times. The decision reflects the growing concern over possible academic bias in research due to corporate financing, particularly at a time when government money is disappearing.
For microbiologists, Antarctica may be the new frontier
Nature: Rather than being a benign block of ice, Antarctica may be teeming with microbial life. Next week Martin Siegert of the University of Bristol in the UK and colleagues will travel to the West Antarctic Ice Sheet to drill into Lake Ellsworth, one of some 380 subglacial lakes in Antarctica. It is thought that those lakes could host exotic bacteria that derive their energy from rocks and minerals. Although all the lakes have been explored remotely with radar, Lake Ellsworth will be only the second one to be physically breached via drilling. Earlier this year a Russian team explored Lake Vostok, the largest and deepest of the Antarctic lakes, but so far those researchers have not found any native microbes. Siegert believes Lake Ellsworth may be the better place to look because it is much smaller than Lake Vostok, its overlying ice is twice as “warm,” and the ice is thinner by almost a kilometer.