Following up on my post of several weeks ago (iGEM 2011: First Thoughts
), here is a bit more on last year's Jamboree. I remain very, very impressed by what the teams did this year. And I think that watching iGEM from here on out will provide a sneak peak of the future of biological technologies.
I think the biggest change from last year is the choice of applications, which I will describe below. And related to the choice of applications is change of approach to follow a more complete design philosophy. I'll get to the shift in design sensibility further on in the post.The University of Washington
: Make it or Break it
I described previously the nuts and bolts of the University of Washington's
Grand Prize winning projects. But, to understand the change in approach (or perhaps change in scope?) this project represents, you also have to understand a few details about problems in the real world. And that is really the crux of the matter -- teams this year took on real world problems as never before, and may have produced real world solutions.
Recall that one of the UW projects was the design of an enzyme that digests gluten, with the goal of using that enzyme to treat gluten intolerance. Candidate enzymes were identified through examining the literature, with the aim of finding something that works at low pH. The team chose a particular starter molecule, and then used the "video game" Foldit
to re-design the active site in silico
so that it would chew up gluten (here is a very nice Youtube video on the Foldit story from Nature
). They then experimentally tested many of the potential improvements. The team wound up with an enzyme that in a test tube is ~800 times better than one already in clinical trials. While the new enzyme would of course itself face lengthy clinical trials, the team's achievement could have an enormous impact on people who suffer from celiac disease, among many other ailments.
From a story in last week's NYT Magazine ("Should We All Go Gluten-Free?
"), here are some eye-opening stats on celiac disease, which can cause symptoms ranging from diarrhea to dramatic weight loss:
- Prior to 2003, prevalence in the US was thought to be just 1 in 10,000: widespread testing revealed the actual rate was 1 in 133.
- Current estimates are that 18 million Americans have some sort of gluten intolerance, which is about 5.8% of the population.
- Young people were 5x more likely to have the disease by the 1990s than in the 1950s based on looking at old blood samples.
- Prevalence is increasing not just in US, but also worldwide.
In other words, celiac disease is a serious metabolic issue that for some reason is affecting ever larger parts of the global population. And as a summer project
a team of undergraduates may have produced a (partial) treatment for the disease. That eventual treatment would probably require tens of millions of dollars of further investment and testing before it reaches the market. However, the market for gluten-free foods, as estimated in the Times
, is north of $6 billion and growing rapidly. So there is plenty of market potential to drive investment based on the iGEM project.
The other UW project is a demonstration of using E. coli to directly produce diesel fuel from sugar. The undergraduates first reproduced work published last year from LS9 in which E. coli was modified to produce alkanes (components of diesel fuel -- here is the Science paper
by Schirmer et al). Briefly, the UW team produced biobricks -- the standard format used in iGEM -- of two genes that turn fatty acids into alkanes. Those genes were assembled into a functional "Petrobrick". The team then identified and added a novel gene to E. coli that builds fatty acids from 3 carbon seeds (rather than the native coli system that builds on 2 carbon seeds). The resulting fatty acids then served as substrates for the Petrobrick, resulting in what appears to be the first report anywhere of even-chain alkane synthesis. All three genes were packaged up into the "FabBrick", which contains all the components needed to let E. coli process sugar into a facsimile of diesel fuel.
The undergraduates managed to substantially increase the alkane yield by massaging the culture conditions, but the final yield is a long way from being useful to produce fuel at volume. But again, not bad for a summer project. This is a nice step toward turning first sugar, then eventually cellulose, directly into liquid fuels with little or no purification or post-processing required. It is, potentially, also a step toward "Microbrewing the Bioeconomy
". For the skeptics in the peanut gallery, I will be the first to acknowledge that we are probably a long way from seeing people economically brew up diesel in their garage from sugar. But, really, we are just getting started. Just a couple of years ago people thought I was all wet forecasting that iGEM teams would contribute to technology useful for distributed biological manufacturing of fuels. Now they are doing it. For their summer projects. Just wait a few more years.
Finally -- yes, there's more -- the UW team worked out ways to improve the cloning efficiency of so-called Gibson cloning. They also packaged up as biobricks all the components necessary to produce magnetosomes in E. coli. The last two projects didn't make it quite as far as the first two, but still made it further than many others I have seen in the last 5 years.
Before moving on, here is a thought about the mechanics of participating in iGEM. I think the UW wiki is the about best I have seen. I like very much the straightforward presentation of hypothesis, experiments, and results. It was very easy to understand what they wanted to do, and how far they got. Here is the "Advice to Future iGEM Teams
" I posted a few years ago. Aspiring iGEM teams should take note of the 2011 UW wiki -- clarity of communication is part of your job.Lyon-INSA-ENS
: Cobalt Buster
The team from Lyon took on a very small problem: cleaning up cooling water from nuclear reactors using genetically modified bacteria. This was a nicely conceived project that involved identifying a problem, talking to stakeholders, and trying to provide a solution. As I understand it, there are ongoing discussions with various sponsors about funding a start-up to build prototypes. It isn't obvious that the approach is truly workable as a real world solution -- many questions remain -- but the progress already demonstrated indicates that dismissing this project would be premature.
Before continuing, I pause to reflect on the scope of Cobalt Buster. One does
wonder about the eventual pitch to regulators and the public: "Dear Europe, we are going to combine genetically modified organisms and radiation to solve a nuclear waste disposal problem!" As the team writes on its Human Practices page: "In one project, we succeed to gather Nuclear Energy and GMOs
. (emphasis in original)" They then acknowledge the need to "focus on communication". Indeed.
Here is the problem they were trying to solve: radioactive Cobalt (Co) is a contaminant emitted during maintenance of nuclear reactors. The Co is typically cleaned up with ion exchange resins, which are both expensive and when used up must be appropriately disposed of as nuclear waste. By inserting a Co importer pump into E. coli, the Lyon team hopes to use bacteria to concentrate the Co and thereby clean up reactor cooling water. That sounds cool, but the bonus here is that modelling of the system suggests that using E. coli as a biofilter in this way would result in substantially less waste. The team reports that they expect 8000kg of ion exchange resins could be replaced with 4kg of modified bacteria. That factor of 2000 in volume reduction would have a serious impact on disposal costs. And the modified bug appears to work in the lab (with nonradioactive Cobalt), so this story is not just marketing.
The Lyons team also inserted a Co sensor into their E. coli strain. The sensor then drove expression of a protein that forms amyloid fibers, causing the coli in turn to form a biofilm. This biofilm would stabilize the biofilter in the presence of Co. The filter would only be used for a few hours before being replaced, which would not give the strain enough time to lose this circuit via selection.Imperial College London
Last, but certainly not least, is the very well thought through Imperial College
project to combat soil erosion by encouraging plant root growth. I saved this one for last because, for me, the project beautifully reflects the team's intent to carefully consider the real-world implications of their work. There are certainly skeptics out there who will frown on the extension of iGEM into plants, and who feel the project would never make it into the field due to the many regulatory barriers in Europe. I think the skeptics are completely missing the point.
To begin, a summary of the project: the Imperial team's idea was to use bacteria as a soil treatment, applied in any
number of ways, that would be a cost-effective means of boosting soil
stability through root growth. The team designed a system in which genetically modified bacteria would be attracted to plant roots, would then take up residence in those roots, and would subsequently produce a hormone that encourages root growth.
The Auxin system was conceived to combine existing components in very interesting ways. Naturally-occurring bacteria have already been shown to infiltrate plant roots, and other soil-dwelling bacteria produce the same growth hormone that encourages root proliferation.
Finally, the team designed and built a novel (and very clever) system for preventing leakage of transgenes through horizontal gene transfer. On the plasmid containing the root growth genes, the team also included genes that produce proteins toxic to bacteria. But in the chromosome, they included an anti-toxin gene. Thus if the plasmid were to leak out and be taken up by a bacterium without the anti-toxin gene, any gene expression from the plasmid would kill the recipient cell.
The team got many of these pieces working independently, but didn't quite get the whole system working together in time for the international finals. I encourage those interested to have a look at the wiki
, which is really very good.The Shift to Thinking About Design
As impressive as Imperial's technical results were, I was also struck by the integration of "human practices" into the design process. The team spoke to farmers, economists, Greenpeace -- the list goes on -- as part of both defining the problem and attempting to finesse a solution given the difficulty of fielding GMOs throughout the UK and Europe. And these conversations very clearly impacted the rest of the team's activities.
One of the frustrations felt by iGEM teams and judges alike is that "human practices" has often felt like something tacked on to the science for the sake of placating potential critics. There is something to that, as the Ethical, Legal, and Social Implications (ELSI) components of large federal projects such as The Human Genome Project and SynBERC appear to have been tacked on for just that reason. Turning "human practices" into an appendix on the body of science is certainly not the wisest way to go forward, for reasons I'll get to in a moment, nor is it politically savvy in the long term
. But if the community is honest about it, tacking on ELSI to get funding has been a successful short-term
The Auxin project, along with a few other events during the finals, helped crystallize for me the disconnect between thinking about "human practices" as a mere appendix while spouting off about how synthetic biology will be the core of a new industrial revolution, as some of us tend to do. Previous technological revolutions have taught us the importance of design
, of thinking the whole project through at the outset in order to get as much right as possible, and to minimize the stuff we get wrong. We should be bringing that focus on design to synthetic biology now.
I got started down this line of thought during a very thought-provoking conversation with Dr. Megan Palmer
, the Deputy Director for Practices at SynBERC
. (Apologies to you, Megan, if I step your toes in what follows -- I just wanted to get these thoughts on the page before heading out the door for the holidays.) The gist of my chat with Megan was that the focus on safety and security as something else
, as an activity separate from the engineering work of SB, is leading us astray. The next morning, I happened to pass Pete Carr and Mac Cowell having a chat just as one of them was saying, "The name human practices sucks. We should really change the name." And then my brain finally -- amidst the jet lag and 2.5 days of frenetic activity serving as a judge for iGEM -- put the pieces together. The name does suck. And the reason it sucks is that it doesn't really mean anything.
What the names "human practices" and "ELSI" are trying to get at is the notion that we shouldn't stumble into developing and using a powerful technology without considering the consequences. In other fields, whether you are thinking about building a chair, a shoe, a building, an airplane, or a car, in addition to the shape you usually spend a great deal of time thinking about where the materials come from, how much the object costs to make, how it will be used, who will use it, and increasingly how it will be recycled at end of use. That process is called design, and we should be practicing it as an integral part of manipulating biological systems.
When I first started as a judge for iGEM, I was confused by the kind of projects that wound up receiving the most recognition. The prizes were going to nice projects, sure, but those projects were missing something from my perspective. I seem to recall protesting at some point in that first year that "there is an E in iGEM, and it stands for Engineering." I think part of that frustration was the pool of judges was dominated for many years by professors funded by the NIH, NRC, or the Welcome Trust, for example -- scientists who were looking for scientific results they liked to grace the pages of Science or Nature -- rather than engineers, hackers, or designers who were looking for examples of, you know, engineering.
My point is not that the process of science is deficient, nor that all lessons from engineering are good -- especially as for years my own work has fallen somewhere in between science and engineering. Rather, I want to suggest that, given the potential impact of all the science and engineering effort going into manipulating biological systems, everyone involved should be engaging in design. It isn't just about the data, nor just about shiny objects. We are engaged in sorting out how to improve the human condition, which includes everything from uncovering nature's secrets to producing better fuels and drugs. And it is imperative that as we improve the human condition we do not diminish the condition of the rest of the life on this planet, as we require that life to thrive in order that we may thrive.
Which brings me back to design. It is clear that not every experiment in every lab that might move a gene from one organism to another must consider the fate of the planet as part of the experimental design. Many such experiments have no chance of impacting anything outside the test tube in which they are performed. But the practice
of manipulating biological systems should be done in the context of thinking carefully about what we are doing -- much more carefully than we have been, generally speaking. Many fields of human endeavor can contribute to this practice. There is a good reason that ELSI has "ethical", "legal", and "social" in it.
There have been a few other steps toward the inclusion of design in iGEM over the years. Perhaps the best example is the work designers James King and Daisy Ginsburg did with the 2009 Grand Prize Winning team from Cambridge (see iGEM 2009: Got Poo
?). That was lovely work, and was cleverly presented in the "Scatalog". You might argue that the winners over the years have had increasingly polished presentations, and you might worry that style is edging out substance. But I don't think that is happening. The steps taken this year by Imperial, Lyon, and Washington toward solving real-world problems were quite substantive, even if those steps are just the beginning of a long path to get solutions into people's hands. That is the way innovation works in the real world.