In collaboration with scientists from the Wadsworth Center of the New York State Department of Health, the team is working to harness the reaction to develop a "nanoswitch" for a variety of applications, from targeted drug delivery to genomics and proteomics to sensors.
The research is part of a burgeoning discipline called "quantum biology," which taps the skyrocketing power of today's high-performance computers to precisely model complex biological processes. The secret is quantum mechanics -- the much-touted theory from physics that explains the inherent "weirdness" of the atomic realm.
Reporting in the February 2007 issue of Biophysical Journal, the researchers describe a mechanism to explain how an intein -- a type of protein found in single-celled organisms and bacteria -- cuts itself out of the host protein and reconnects the two remaining strands. The intein breaks a protein sequence at two points: first the N-terminal, and then the C-terminal. This aspect of the project, which is led by Saroj Nayak, associate professor of physics, applied physics, and astronomy at Rensselaer, focuses on the C-terminal reaction.
Another Rensselaer team previously found that the reaction at the C-terminal speeds up in acidic environments. But to control the reaction and use it as a nanoswitch, a better understanding of the mechanism behind this reaction is needed, according to Philip Shemella, a doctoral student in physics at Rensselaer and corresponding author of the current paper.
"You can use this protein that cuts itself and joins the pieces together in a predictable way," he said. "It already has a function that would be nice to harness for nanotechnology purposes." And because the reaction may be sensitive to light and other environmental stimuli, the process could become more than just a two-way switch between "on" and "off."
The researchers revealed the details of the reaction mechanism by applying the principles of quantum mechanics -- a mathematical framework that describes the seemingly strange behavior of the smallest known particles. For example, quantum mechanics predicts that an electron can be in two different places at the same time; or that an imaginary cat can be simultaneously dead and alive, as suggested by one famous thought experiment.
Until recently, scientists could not apply quantum mechanics to biological systems because of the large numbers of atoms involved. But the latest generation of supercomputers, along with the development of efficient mathematical tools to solve quantum mechanical equations, is making these calculations possible, according to Shemella.
"Typically, quantum mechanics has been applied to solid-state problems because the symmetry makes the calculation smaller and easier, but there's really nothing different physically between a carbon atom in a protein and a carbon atom in a nanotube," he said. "Even though a protein is such an asymmetric, complex system, when you really zoom into the quantum mechanical level, they are just atoms. It doesn't matter if strange things are happening; it's still just carbon, nitrogen, hydrogen, and oxygen."
Quantum mechanics allows researchers to do things that can't be done with classical physics, such as modeling the way chemical bonds break and form, or including the effect of proton "tunneling" -- allowing protons to move through energy barriers that normal logic would deem impossible.
For this project, the researchers used computing facilities at Rensselaer's Scientific Computation Research Center (SCOREC) and the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign. In the future, they hope to take advantage of Rensselaer's new Computational Center for Nanotechnology Innovations -- a $100 million partnership between Rensselaer, IBM, and New York state to create one of the world's most powerful university-based supercomputing centers.
The additional computing power will allow them to model complex biological systems with even greater accuracy: "The more atoms you include, the more accurate your system," Shemella said.
Jason Gorss | EurekAlert!
NASA's James Webb Space Telescope completes final cryogenic testing
21.11.2017 | NASA/Goddard Space Flight Center
Previous evidence of water on mars now identified as grainflows
21.11.2017 | US Geological Survey
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
21.11.2017 | Physics and Astronomy
21.11.2017 | Physics and Astronomy
21.11.2017 | Life Sciences