World's First Artificial Enzymes Created From Synthetic Genetic Material

photo credit: University of Liverpool Faculty of Health and Life Sciences, via Flickr. CC BY 2.0

Scientists have made a breakthrough in the field of synthetic biology by creating, for the first time, enzymes from artificial genetic material that does not exist in nature. This exciting new work not only offers new insights into the origins of life on Earth, but also has implications for our search for extraterrestrial life on other planets.

The foundations for this study were laid a couple of years ago when UK scientists created synthetic versions of DNA, the molecule that carries the genetic information of all living things on Earth, and its close chemical cousin, RNA. This synthetic genetic material was created using the same building blocks that are found in DNA and RNA, but the scientists strung them together with different molecules. These resulting synthetic molecules, which were dubbed ‘XNAs,’ or xeno nucleic acid, were found to be capable of storing and passing on genetic information.

Although it was widely believed that DNA and RNA, together with proteins, were the only molecules that could form enzymes, the same researchers have now demonstrated that it is possible to create synthetic enzymes using only these XNAs. These molecules, which have been named ‘XNAzymes,’ were capable of chopping up and stitching together bits of RNA, just like natural enzymes. One of them was even capable of joining up fragments of XNA.

Enzymes, nature’s catalysts, are fundamental to life on Earth because almost all of the biochemical reactions taking place in cells are inefficient at ambient temperatures. Enzymes are therefore required to give reactions, such as synthesizing DNA or digesting food, a kick-start, allowing them to occur at rates sufficient for life to exist.

Although the majority of enzymes are proteins, some RNA molecules possess catalytic activity. It’s widely believed that the evolution of early pieces of genetic information, which may have been RNA, into self-replicating enzymes was likely a key event in the emergence of life on Earth. This work is therefore important because it recreates one of the earliest stages towards life. However, it also teases us with the possibility that life could evolve without DNA or RNA, which are widely regarded as the prerequisites for life.

“Our work suggests that, in principle, there are a number of possible alternatives to nature’s molecules that will support the catalytic processes required for life,” said lead scientist Philip Holliger. “Life’s ‘choice’ of RNA and DNA may just be an accident of prehistoric chemistry.”

Because it is possible to create genetic material and enzymes from building blocks that don’t occur naturally, this suggests that life could emerge from different molecular backbones on other planets. This could therefore “potentially widen the number of exoplanets that one could consider would be hospitable for some form of life,” according to Holliger.

This work, the researchers say, could also lead to a new wave of treatments for a variety of diseases. As explained by Dr. Holliger, it may be possible to synthesize XNAs that are capable of chopping up pieces of RNA produced from cancer genes or fragments of viral RNA. And because the XNAs don’t occur naturally, it is unlikely that they will be recognized and destroyed by other enzymes in the body.

[Via Nature, the Medical Research Council, BBC News, New Scientist and The Independent]

ORIGINAL: IFLScience

by Justine Alford

December 2, 2014

DIY Exoplanet Detector Using a DSLR

Your DSLR can do much more than just take a few nice portraits or the occasional vacation photos – with some DIY magic you can actually turn it into a device which can detect planets outside our solar system – something that 20 years ago was impossible even with the most sophisticated telescopes.

So how can you achieve this? David Schneider who you can see in the video above was able to use his Canon EOS Rebel XS (a.k.a Canon 1000D) camera. With old manual-focus 300mm Nikon telephoto lens he got from eBay for under a $100 with a $17 adapter

After he had his camera setup Schneider needed a way to track stars in a very precise way. There are of course very expensive options that you can buy, However as a DIY enthusiast he decided to create something on his own based on a device called a barn door tracker (a relatively simple device that will allow you to shoot longer exposures and track the stars to compensate for the Earth’s rotation).

Looking online you can find many different designs for creating a barn door tracker (see for example here and here) – some are very basic and manual and some are more advanced and use a computer – which is exactly what Schneider decided to do (using arduino) – costing him another few dollars (including an inexpensive power adapter that can run his camera for hours).

Buying and building the hardware you see in the video was actually the easy part. The hard part was finding a way to look for a target star, track it and be able to measure the brightness of the star changing as a planet passes by it. Now it is important to realize at this point that the star chosen for this task – called simply HD 189733 (about 63 light-years away from us in the constellation of Vulpecula) is known to have an exoplanet orbiting it since 2005 – so Schneider did not actually discover a planet outside our solar system but was “only” able to confirm its existence. However given the very basic and inexpensive equipment he used – this is still a pretty impressive achievement. Finding a new expoplanet this way will probably require a lot more patience but it might not be impossible if you have the right information from other observations of the same region of space.

All this makes us wonder if NASA can actually do something that will significantly improve our ability to detect expoplanets and cost a fraction of any existing observatory. By funding a competition between companies and entrepreneurs to create a low cost but functional hardware that will be sold at a relatively low price to the consumer (say below $300 or so) and use any DSLR with a telephoto lens and a simple distributed computing software along the lines of SETI@home or Orbit@home that will coordinate worldwide efforts to locate, track and confirm the existence and orbits of exoplanets – it can drastically improve the rate in which we discover and confirm planets outside our solar system (and help raise a new generation interested in Astronomy).

Astrophotography is nothing new of course and we have covered the topic in the past including How To Photograph The Milky Way (or Die Trying) and PBS: The Beauty of Space Photography.

VIA: IEEE spectrum (where you can read Schneider’s full report).

ORIGINAL: Lens Vid
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