ERJ staff report (DS)
Michigan - US website EVWorld has posted a two-part interview with Dr. Thomas Sharkey of Michigan State University in which Dr Sharkey outlines progress on bio-isoprene research in his department.
The first clip is around 11 minutes long. The second is about 15. In the first clip Dr Sharkey responds to some fairly ill-informed questions from an EVWorld reporter, but eventually discusses progress at his department. He notes that isoprene is a common biological molecule. He explains that he has identified a series of genes which lead to a metabolic pathway to making isoprene gas. Those genes can be transplanted into micro-organisms.
He does not talk about improving the yield of the micro-organisms until the end of the clip. He then goes off on a sidetrack about the Henry Wickham adventure and disease resistance in Hevea Brasiliensis, the potential spread of fungus and other diseases through southeast Asia. Dr Sharkey also refers to the potential to make allergen-free polyisoprene for glove applications. Sharkey acknowledges he is in a race and claims to have more genes isolated than anyone else. He says he has not made any polyisoprene. He said (in the final minute of the first interview), he can improve the yield by using four different genes, one of which is his isoprenesynthase. He said the latest cuclture generates too much isoprene gas from the culture.
At the start of the second clip, Dr Sharkey discusses the scale-up from lab scale to industrial scale. He said his lab-scale results are being taken by the tech transfer unit of his university and converted to industrial scale - in 3000-litre reactors. The next step is a scale-up to 50,000 litre reactors. At that scale, he said, the isoprene would be cheaper than from trees.
Dr Sharkey then discusses the differences between cis-polyisoprene and trans-polyisoprene. The interviewer senses that this is too technical so moves the interview forward to the timescales of introduction of this technology. Around 5 minutes into the second part, Dr Sharkey mentions the Goodyear-Genencor partnership claiming, somewhat unfairly, that Goodyear gave Genencor $50 million and they made two tyres from it, suggesting that the price point there is $25 million per tyre. He said Genencor started from his own enzymes, but he only got a dinner out of it, whereas Genencor got $50 million.
He said he does not expect bio-isoprene to eliminate the NR industry, but to provide a second source of supply, in case of shortage of supply due to increased demand, or if disease catches hold in Southeast Asia.
The interviewer asks about alternatives and Dr Sharkey discusses guayule and Russian dandelions, suggesting that the chain length in those molecules is too short, which results in poor quality rubber.
At around 12 minutes in, Dr Sharkey says more work is needed to improve the yield to the point of commercial viability. Once that is achieved, he said the chemical engineers will take over. He said he thinks he will soon achieve commercial isoprene yields.
This is an external link and should open in a new window. If the window does not appear, please check your pop-up blocking software. ERJ is not responsible for the content of external sites.
Video and story from EVWorld
First part of video interview from YouTube
Second part of video interview from YouTube