Brian Cox, in his excellent first Wonders of Life programme extracted DNA fibres from his own saliva. What he didn’t explain was how the few cells extracted from his cheek by swilling out his mouth with saliva could produce thick curdy strands of DNA. In the cell the DNA is tightly supercoiled. When released it bursts out and uncoils. Every single cell contains up to 2m length of DNA. Each cell is only 1/100th mm in diameter so that’s a pretty amazing piece of packaging. If you try the experiment, you can pull out fine strands of DNA for quite a distance before they break. With practice and a steady hand you could probably pull a foot or two. A pity most of us don’t have the microscopes to see any further into this iconic substance.
The Wonder of Proton Gradients
Sam Wollaston, in the Guardian, pretending not to understand Brian Cox’s Wonders of Life, actually hit on a good paraphrase: “Life, that's it – not a thing, but a series of chemical processes that harness the flow of energy to create islands of order, like a tree, or me.” Actually, Cox was excellent in explaining the emerging thermodynamic, chemical gradient theory of the origin of life, as expounded in detail in Nick Lane’s Life Ascending. Absolutely brilliant that Cox was able to present this on primetime BBC TV.
8 Great Technologies
Perhaps the greatest surprise of the year so far has been the UK government boldly announcing that it will fund “Eight Great Technologies” to the tune of £464 million. Having proclaimed for three decades that governments cannot pick winners, the Tory wing of the Coalition (this policy is specifically David Willett’s baby) is putting money where its new-found mouth is on a Rabelaisian scale. The famous 8 are:
£464 of the £600 additional funding for science.
1.The big data revolution and energy-efficient computing
2. satellite data analysis
3. robots and other autonomous systems.
4. Synthetic biology
5. Regenerative Medicine
7. Advanced materials and nanotechnology
8. Energy and its Storage
The policy paper, published by Policy Exchange, seems well-informed and the highlighted fields sound plausible. But, as in the past, the strengths that the government wishes to support lie largely in the universities. The number of world-class companies able to bring these technologies to market is limited.
We must wish the strategy well but a similar report in 1950 could have pointed with real confidence to four much greater technologies in which Britain had world leadership or at least top-ranking status: commercial jet airliners; computing; electronics and telecommunications; nuclear power. These are massive industries, far bigger in scale than the Famous 8, and all failed miserably.
Meanwhile, the government’s next big initiative is the £33 billion HS2 project, a large part of which will be sourced overseas because Britain’s pioneer railway manufacturing industry lost its way many decades ago.
It’s no great surprise that in the race to commercialize graphene two companies (Samsung – 407 patents and IBM – 134) far outstrip the entire UK patent haul: 54. Samsung and IBM are hi-tech fabricators on an enormous scale. They have the industrial know-how and when a new material like graphene comes along they work out how it might be developed industrially. Contrast that with the typical UK situation in which, following a big discovery in a university lab, a spin-off company is funded on a very small scale with no big-industry expertise at all. The likely outcome is a no-brainer. Of course spin-offs and start-ups sometimes succeed but what is really needed is for existing medium to large engineering firms to be encouraged to take on board development of major new technologies. When Frank Whittle invented the jet engine, he founded a start-up. But it required Rolls Royce to turn it into a commercial hit. Britain doesn’t have a Samsung or IBM but there must be companies that could bring the right industrial nous to the graphene question.
The Tunnelling Gene
Spider webs, beaver dams, the mating courtyards of bower birds and other examples of natural architecture are surely some of the weirdest products of the genes. These structures are not learned so must be genetically controlled. Richard Dawkins wrote about them in his second book, The Extended Phenotype.
Now, the results of what started as a home experiment by evolutionary biologist Hopi Hoekstra, now at Harvard, are starting to show how this process works. Working with Oldfield mice that construct elaborate burrows with escape tunnels and deer mice that construct only simple tunnels, Hoekstra has homed in on the genetic loci involved. It turns out that they are modular, with 3 genetic loci responsible for the long tunnels and a fourth for the escape hatch. The next stage will be to engineer deer mouse with the advanced tunnelling genes of the Oldfield mice and watch the digging.
This kind of pick and mix modularity controlled by very few genes has been observed in body traits (eg butterfly wing patterns) but this is the first time it has been seen in behaviour. The fact that complex organs and behaviour can be pick-and-mixed like this and switched relatively easily by genetic switches clearly makes evolutionary adaptation less of a mystery.
Nature, 2013, 493, pp. 402-5
Chemistry Assembles Life
Paul Davies has provocatively declared that the mystery of the origin of life won’t be solved by chemistry. I’m sure he’s wrong. He claims that there is a fundamental divide between information-rich, hierarchically organized biology and chemistry but much evidence shows that this barrier is illusory. Primitive cell-like membranes made of lipids are easy to make by chemical self-assembly. Once you have such a structure you have a contained environment which already has the biological, informational property: other chemicals can either be inside or outside the lipid membrane. Ribozymes, RNA molecules that can carry information and can replicate, are already primitive informational molecules. They are both enzyme and replicators and can catalyse their own replication. Finally, energy gradients are necessary for biological metabolism. Chemical energy gradients, similar to those found in the cell, have been found in open ocean environments at smokers, where hot gases emerge at high temperature from the ocean floor. Put these systems together and you can see how primitive self-replicating cells might have evolved. See Nick Lane’s Life Ascending. There are countless other areas where chemicals show self-organizing behaviour: there is a whole field of self-assembling chemistry within the ambit of nanoscience.
One of the biggest stories of the New Year was hidden in a small item tucked away on an inside page of the Guardian. Network Rail in the UK has signed a 10 year deal to get all its electricity from nuclear power supplied by EDF. Couple that with the current investment plan that aims to have 75% of UK trains electric over around the same period and we have a jump in the necessary decarbonisation of transport.
Of course, it’s somewhat arbitrary to say that in a grid electricity “comes from” a certain source. Only the bills can say that. And its only global decarbonisation that really matters. But in a war the world has been losing we need some symbolic breakthroughs and this is one. We don’t yet know what will power the cars and lorries of the future (electricity, hydrogen, solar-generated biofuels?) but carbon-free electric rail is the only way for rail and the sooner it happens worldwide the better. So, how come the reticence about trumpeting nuclear rail? Don't write – we all know the answer.
Chicken Wire Cheeps
Graphene may have stolen carbon nanotubes’ thunder but the nano-coiled “chicken wire” has an almost 20 year headstart. The IBM Research centre in New York is making impressive progress on harnessing self-assembled arrays of them. Now in Nature Nanotechnology they report a wet chemical self assembly technique that can produce 10,000 transistors in a way that is compatible with conventional top-down fabrication. The transistors are mostly well aligned, make good electrical connections and have a 90% success rate. Whether the technique is scalable to the point where it can rival silicon fabrication is an open question but the difficult interface between chemical self-assembly and precision top-down fabrication has been bridged.
Nature Nanotechnology, 2012, 7, pp.787-91.
Write its Name in Water
One of the revelations of the age is what DNA can do once released from its biological role in the cell. DNA as a nano material came to fame in 2006 when nano smileys made form it graced the cover of Nature magazine. Since then it has twisted into every shape under the sun. Now a Korean/American/Japanese team, based at Cornell has produced a DNA shape memory gel.
Hydrogels are jelly-like materials made mostly of water with large, filamentous molecules holding it together. On removing water from the DNA hydrogel it collapses and behaves like a liquid. It’s the floppiest gel ever made. But it can be shaped and when water is added it returns to the shape give it. In cycles of collapse and regrowth it always returns to the original shape. The researchers demonstrated this by writing its own name in the hydrogel and letting the letters reform form the “liquid” state.
Practical DNA technologies are under development, such as drug delivery systems, but for now the substance is wowing us all over again, as a purely technical material.
Nature Nanotechnology, 2012, 7, 816-820.
The best presents are always those items you've had your eye on for a while but haven’t bought because you thought they were a tad self indulgent. So I was given Paul Jackson's Folding Techniques for Designers (Laurence King Publishers).
There’s a chapter on origami in my book The Gecko's Foot. That is origami as used in technical devices from space arrays to architecture, and also in nature. Paul Jackson’s book is a manual of the principles that allow you to create structures from paper that fold up in remarkable ways. The best knowing examples are lampshades, but readily deployable buildings can be made by the same processes.
In the past, I’ve made leaf-oris and Miura-ori maps but never the more complex patterns. A new challenge for the New Year.
I'm a writer whose interests include the biological revolution happening now, the relationship between art and science, jazz, and the state of the planet