Synthetic Sources of Natural Rubber
Rubber can be made chemically from fossil fuels, but natural rubber from tropical trees is still the best source, and in many cases the only usable one (car tires need a lot of natural rubber for the right combination of strength and elasticity). Besides being difficult to grow and relatively inefficient, rubber trees are also facing a fungal plague that could potentially wipe out natural rubber within the next few years. Many labs (including mine) are trying to find or engineer different sources of biological polymers. According to a neat article in The Economist, two groups are working with dandelions as potential a new source of natural rubber. One group is using RNA interference to knock down the expression of a gene that makes the rubber polymers that the plant already makes difficult to process, and the other is using more traditional breeding technologies to improve rubber production, selecting and crossing high producers. Not only do dandelions already produce significant amounts already, but their fast growth and ability to grow just about anywhere (which makes them such good weeds) may make them a valuable agricultural commodity.
It’s an interesting project in many ways. Biological polymers are a fascinating and very broad subject, and understanding and engineering how enzymes make and break down these polymers will undoubtably be important for industrial biological engineering. Moreover, a sustainable biological method for producing rubber locally (instead of the current synthetic methods) will be important for environmental conservation and decreasing oil dependence.
However, this also means that there will be serious competition for rubber tree farmers, with likely many negative effects for the economies of Malaysia, Thailand, and Indonesia, the world’s top rubber producers. This has already happened, when the first round of synthetic—but not as good—rubber entered the market, as well as when indigo dyes began to be chemically synthesized, irreparably damaging the Indian dye economy. These and other issues are discussed in an interesting article by Political Scientists working at MIT, “Aspects of the political economy of development and synthetic biology” from a special issue of Systems and Synthetic Biology. These are important but often neglected aspects of the discussion of the risks and benefits of the potential applications of synthetic biology.
