Understanding the role of SilE in the production of metal nanoparticles by Morganella psychrotolerans using MicroScale Thermophoresis.

Metal nanoparticle synthesis has been observed in several species of bacteria but the underlying mechanisms of synthesis are not well understood. Morganella psychrotolerans is a Gram-negative psychrophilic bacterium that is able to tolerate relatively high concentrations of Cu and Ag ions, and it is through the associated resistance pathways that this species is able to convert metal ions to nanoparticles. The purpose of this study was to investigate the mechanism of nanoparticle synthesis, looking at the interaction of the metal binding protein SilE with metal ions using MicroScale Thermophoresis (MST). MST assays give a rapid and accurate determination of binding affinities, allowing for the testing of SilE with a range of environmentally significant metal ions. The binding affinities (Kd) of Ag+ and Cu2+ were measured as 0.17 mM and 0.13 mM respectively, consistent with the observations of strong binding reported in the literature, whereas the binding to Al3+ and Co2+ was measured as Kd values of 4.19 mM and 1.35 mM respectively.

Room temperature bioproduction, isolation and anti-microbial properties of stable elemental copper nanoparticles.

In nanoparticle production there are a number of important considerations that must be made. Producing nanoparticles of uniform size and shape is vital, but no less important is ensuring the production process is as efficient as possible in time, cost and energy. Traditional chemical and physical methods of nanoparticle production often involve high temperatures and pressures, as well as the use of toxic substrates; in contrast the bioproduction of nanoparticles is greener and requires a smaller input of energy resources. Here we outline a method for the straightforward bioproduction of stable, uniform elemental (zero-valent) copper nanoparticles at room temperature, and demonstrate how their size and shape can be modified by subsequent pH manipulation. We also highlight a potential application for these biogenic copper nanoparticles by demonstrating their potential to inhibit bacterial growth.

2nd Congress on applied synthetic biology in Europe (Málaga, Spain, November 2013).

The second meeting organised by the EFB on the advances of applied synthetic biology in Europe was held in Málaga, Spain in November 2013. The potential for the broad application of synthetic biology was reflected in the five sessions of this meeting: synthetic biology for healthcare applications, tools and technologies for synthetic biology, production of recombinant proteins, synthetic plant biology, and biofuels and other small molecules. Outcomes from the meeting were that synthetic biology offers methods for rapid development of new strains that will result in decreased production costs, sustainable chemical production and new medical applications. Additionally, it also introduced novel ways to produce sustainable energy and biofuels, to find new alternatives for bioremediation and resource recovery, and environmentally friendly foodstuff production. All the above-mentioned advances could enable biotechnology to solve some of the major problems of Society. However, while there are still limitations in terms of lacking tools, standardisation and suitable host organisms, this meeting has laid a foundation providing cutting-edge concepts and techniques to ultimately convert the potential of synthetic biology into practice.