Procurement News Notice |
|
| PNN | 3813 |
| Work Detail | A new and improved nanoreactor made from the alpha-haemosylin protein pore has been developed by researchers at the University of Oxford in the UK. The nanoreactor can be used to follow a range of aqueous chemical reactions in real time, observe “molecular walkers” and complex biological reaction networks. It might even help in the development of novel biotherapeutic agents. Nanopores can be used to study the individual steps of a covalent chemical reaction thanks to the fact that the ionic current flowing through a pore changes when a molecule undergoes a reaction on its inside wall. The nanostructures can allow researchers to do single-molecule chemistry in aqueous environments, and on microsecond time scales, without having to rely on fluorescent probes. Last year, a team led by Hagan Bayley succeeded in fabricating a nanoreactor based on the alpha-haemolysin pore. Alpha-haemolysin (aHL) is a toxin secreted by the bacterium S. aureus. It contains seven subunits made up of 293 amino acids and the researchers replaced just one of these with a subunit containing an artificial amino acid. They then refolded the chain to make an engineered pore (the nanoreactor). The researchers used their nanoreactor to perform “click chemistry” in which an azide reacts with an alkyne in a copper(I)-catalyzed reaction to form a triazole. Observing reversible chemical reactions Bayley and colleagues have now gone a step further in their new work by introducing a ketone side chain into the nanostructure in which they can now observe reversible chemical reactions. They made their nanopore using a combination of biochemistry and synthetic chemistry in a process known as native chemical ligation, which allows them to introduce artificial amino acids into proteins. “Being able to introduce unnatural amino acids into the aHL pore in this way creates a large variety of reactive side chains that can then be used to study single-molecule aqueous covalent chemistry,” explains Bayley. “In fact, virtually any reaction that occurs in aqueous solution can be examined by the nanoreactor approach.” Revealing "hidden" reactions Aqueous chemistry is important for understanding biological systems and for developing new biotherapeutic agents, for example, he tells nanotechweb.org, and single-molecule chemistry reveals information about reactions that remain "hidden" under normal conditions (in which billions of reactions are performed simultaneously). “Our nanoreactor greatly expands the type of chemistry we can now investigate inside such structures,” he adds. “Indeed, we are now looking forward to using our new structures to examine complex reaction networks and observe molecular walkers (molecules that move step-by-step along an engineered track within the pore) in real time.” |
| Country | United Kingdom , Northern Europe |
| Industry | Chemicals & Fertilizer |
| Entry Date | 03 Sep 2016 |
| Source | http://nanotechweb.org/cws/article/tech/66024 |
