Big Week for “Synthetic” Biology
A jellyfish made of silicone, and a bacterium made in silico
Synthetic biology is traditionally thought of as repurposing existing or designing new biological parts to do novel things. But in a larger sense, it can be thought of as the ability to create biological systems outside the limitations of pesky things like global and evolutionary time scales. This week marks two really stunning bio accomplishments, each fitting into their own definition of “synthetic”.
Whoa, Jellyman: Cal Tech and Harvard biophysicists announced that they had created a sort of “synthetic jellyfish” this week (pictured above left). By taking thin, carefully designed sheets of silicone and layering rat heart muscle cells over them, they were able to make a bell-shaped living device that pulsed and swam just like the bell of a jellyfish.
Heart muscle cells, or cardiomyocytes, naturally grow together in sheets and will automatically “beat” in a petri dish (with the help of a little calcium). If you provide an outside voltage (like a pacemaker) they will beat in unison! The rat-heart-silicone “medusoid” shape contracted, with the beating cells pulling on the silicone substrate just as a jellyfish’s own muscle cells act on its bell to swim.
Of course, this isn’t a real jellyfish, but for extra credit you can read Ferris Jabr’s take on what it would actually take to build one.
Byte-size Bio: The other big news this week comes from Stanford and the J. Craig Venter Institute (gracing the cover of Cell this week, above right). Not content with making the world’s first synthetic organism and synthetic genome (Venter’s ambition knows no bounds), they decided to build a computer model of an entire bacterium. Well, mostly.
They modeled, on a very general scale, the tiny bacterium Mycoplasma genitalium, which only has 525 genes compared to our ~20,000, and all of its internal processes on 128 computers operating for 10 hours. To complete a single cell division, it required half a gigabyte of data. But you have to be careful before you call this a completely “simulated organism”. Normal cells have many, perhaps hundreds, of just different types of genes, and they interact in myriad ways … we have just begun to scratch the surface of those networks. Just look at how complicated even the tiny changes in a cancer cell can be!
By simplifying their model down to 28 minimal systems, their computer program matched the bacterium’s biology as we know it. But a more “realistic” model is going to be exponentially more complicated. Here’s some collected reactions at Tree of Life. But, still … wow!
Modern biology has done a very good job at describing the function of individual genes and proteins, but our next chapter lies in how these interactions build into systems. The “-omics” era will be one where we map how the thousands of parts that we are made of combine to make us whole.Simulations like this will be at the leading edge of that era. But we have a long way to go … how many computers would it take to model the trillions of cells in the human body?
Posts from the ‘synthetic biology’ Category
Playing God – A BBC Documentary About Genetic Engineering (Watch full online)
With great power comes great responsibility. Join Adam Rutherford in this full-hour exploration (The whole thing! Online!) of the progress and perils of our ability to cut and splice the very fabric of life on command.
“Life itself has become a programmable machine.”
That statement is a bit of an exaggeration, maybe, but certainly genes, DNA, etc. (the stuff that life is made of) can be synthesized, cut and glued back together with such ease these days that a first-week undergrad can do it (even without help from a seasoned veteran biologist such as myself). You could do it in your garage if you wanted. And where the genetic engineering of yesterday was all about putting a gene or two from one organism into another (like this paper, the precursor to Monsanto’s methods), the ease and cheapness of manipulating the tools of synthetic biology create an infinite pool of possibilities for completely human-designed life forms.
Rest easy, though. When it comes to completely synthetic life, we are still looking at a field in its infancy. Although smart dudes like Craig Venter have succeeded in creating a completely synthetic bacterium, it is an enormously difficult, sensitive and expensive thing to do. I really can’t emphasize how difficult it is, actually. But now is the time, in the early days of meaningful synthetic biology, as prices drop and methods improve, to ask ourselves what is appropriate and what is not.
This will be a global question, and a difficult one. For every drought-resistant strain of wheat that allows us to feed millions of starving children, we can not create another seed monopoly that promotes irresponsible use of herbicides. How do we ensure that the methods used to make plastic-producing bacteria are not the same methods that can produce dangerous bioterrorism strains? How do you feel about having “biohackers” able to order genes and bacteria at will, maybe around the corner from where you live?
Scientists will need to have open discussions. Nonscientists will have to be part of that discussion. This documentary is a must-watch for anyone who wants to know where the future of synthetic biology is headed.