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Recap SD-CAB Symposium 2012 "Food and Fuels in the 21st Century" - Part II

It has been quite a while since my last post. I owe the readers of my blog the second part of the summary of the "Food and Fuels in the 21st Century" Symposium I attended earlier this year. Rather than detailed, by the minute notes, I thought I would just highlight some of the talks I thought were interesting in order to at least share some of my experiences with the everyone before this gets lost in the midst of time. These are highlights from talks that were held Friday and Saturday.



Steve Kay talked about the difficulties of studying complex networks in plants and used the circadian transcriptional network as an example. He showed that straight-forward genetics has limitations when trying to study networks that have high redundancies. To tackle this problem, his lab did the following:

  1. They built a library of DNA motifs are associated with different time of days conserved between Arabidopsis and the rice plant.
  2. The lab also cloned all 2600 or so transcription factors and then used reverse genetics to identify the functions of these transcription factors.
  3. Lastly, using computational approaches, the group looked for two genes that were perfectly correlated and asked under which circumstances (e.g. gene knock-outs) the correlation is broken.
In hindsight, this was one of the most memorable talks because the science so well done. The matter was complex, but the material was presented in a straightforward way without dumbing things down. Steve Kay just is a fantastic speaker! The most memorable quote:"Oh, and this figure is just to show that we are scientists, and we do things very precisely!"

Xun Wang represented Sapphire Energy. The talk mainly revolved around the way Sapphire Energy works. Generally, strains are developed, cultivated, harvested, and extracted. The company aims to produce green crude (algal oil that need no further modifications before they can be processed into biofuels). Interestingly, to reduce cost many nutrients are recycled back into the ponds after extraction. Their research is focused around yield improvement, cultivation (how to protect algae in large open ponds), process development and biomass conversion. This process had a lot of similarities to other energy crop companies like Ceres, SG Biofuels or Monsanto. The similarity is not coincidental as Sapphire Energy seeks to emulate the industrial agricultural model (large scale cultivation, and heavy use of chemicals to control contamination) to produce algal biofuels. Other than that, the talk was very general, highlighting the progress the company has made in building the demonstration plant in New Mexico.

Gerardo Toledo spoke on Synthetic Genomics' behalf. Synthetic Genomics' approach lies in recognizing that the bio diversity represents a reservoir of potential solutions. The company in collaboration with the Craig Venter Institute is tapping this reservoir of solutions by collecting vast metagenomic DNA sequences from bacteria and other microorganisms all across the world. The company has also developed a lot of technology that enables them to design pathways, and use yeast to assemble bacterial genomes.

Stephen Mayfield talked about the benefits of using algae for biofuels production. In general, Stephen Mayfield is recognized as one of the leading researchers in the field of algal biotechnologies. This talk particularly focused on the development of a synthetic 5'UTR library. The 5'UTR region is particularly important in algae because it is the main way how mRNA stability is controlled. Combined with other molecular and genetics tools, the Mayfield lab showed that it was possible to delete  and reinsert genes in a different location. Stephen Mayfield made the point that sometimes functional units ought to be switched rather than individual genes. He used the PSII system as an example to illustrate that  trying to optimize 7 complexes in PSII would be far too complex (necessary diversity of the library is 20^1085 which is much higher than the number of molecules in the universe). As Gerardo Toledo, Stephen Mayfield suggested that whole functional units from existing diversity could be swapped in - sort of like trying to put a Yaris engine into a New Beetle. To demonstrate the point that algal biotechnologies are not as bad as commonly believed, he demonstrated that algae can be engineered to correctly express and fold surface antigens which they could not do so before. He ended the talk by suggesting that this kind of algae could be used for vaccinations - an intriguing thought.

Tasios Melis held another talk I particularly enjoyed. In his talk, Tasios Melis demonstrated that algae can be induced to produce hyrdogen gas when engineered and cultured in such a way that oxygen is not the final electron acceptor. Professor Melis postulated that this is a good first step but that because hydrogen storage is not a trivial challenge, other ways needed to be found to store energy. His lab engineered algal strains to produce isoprenes (C5H8). The production of isoprenes is particularly elegant in the Melis lab because production, collection and separation are very simple. Because isoprenes are volatile gases, cell assocation seems to be negligible. Instead, the gas separates out into the gas phase. Because isoprenes have a relatively high boiling temperature compared to other gases, collecting the produced isoprene is also easy: just cool the collection chamber to 4C and the isoprene will condensate from the air.

Other organizations present worth mentioning were Ceres, Monsanto and SG Biofuels - all energy crop companies with similar models but different energy crop targets and strengths. Life Technologies was also there showcasing their extensive array of standardized cloning and strain kits and highlighting the development of a synthetic biology platform for algae.

I apologize if this post is not as detailed and more technical than usual. This is the only way I knew to share what I have learned in a timely manner before things get completely lost in time. But if people have questions, feel free to ask, and I will consult my notes and answer as best as I can.

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