ExxonMobil and Synthetic Genomics Report Breakthrough in Algae Biofuel Research

June 19, 2017

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(ExxonMobil) Algae strain developed and modified by Synthetic Genomics more than doubled oil production; Additional research and testing required before commercial application; Results published in peer-reviewed journal Nature Biotechnology -- ExxonMobil and Synthetic Genomics Inc. today announced a breakthrough in joint research into advanced biofuels involving the modification of an algae strain that more than doubled its oil content without significantly inhibiting the strain’s growth.

Using advanced cell engineering technologies at Synthetic Genomics, the ExxonMobil-Synthetic Genomics research team modified an algae strain to enhance the algae’s oil content from 20 percent to more than 40 percent. Results of the research were published today in the peer-reviewed journal Nature Biotechnology by lead authors Imad Ajjawi and Eric Moellering of Synthetic Genomics.

Researchers at Synthetic Genomics’ laboratory in La Jolla discovered a new process for increasing oil production by identifying a genetic switch that could be fine-tuned to regulate the conversion of carbon to oil in the algae species, Nannochloropsis gaditana. The team established a proof-of-concept approach that resulted in the algae doubling its lipid fraction of cellular carbon compared to the parent – while sustaining growth.

“This key milestone in our advanced biofuels program confirms our belief that algae can be incredibly productive as a renewable energy source with a corresponding positive contribution to our environment,” said Vijay Swarup, vice president for research and development at ExxonMobil Research and Engineering Company. “Our work with Synthetic Genomics continues to be an important part of our broader research into lower-emission technologies to reduce the risk of climate change.”

“The major inputs for phototropic algae production are sunlight and carbon dioxide, two resources that are abundant, sustainable and free,” said Oliver Fetzer, Ph.D., chief executive officer at Synthetic Genomics. “Discoveries made through our partnership with ExxonMobil demonstrate how advanced cell engineering capabilities at Synthetic Genomics can unlock biology to optimize how we use these resources and create solutions for many of today’s sustainability challenges – from renewable energy to nutrition and human health.”

Algae has been regarded as a potential sustainable fuel option, but researchers have been hindered for the past decade in developing a strain that is high in oil content and grows quickly – two critical characteristics for scalable and cost-efficient oil production. Slower growth has been an adverse effect of previous attempts to increase algae oil production volume.

A key objective of the ExxonMobil-Synthetic Genomics collaboration has been to increase the lipid content of algae while decreasing the starch and protein components without inhibiting the algae’s growth. Limiting availability of nutrients such as nitrogen is one way to increase oil production in algae, but it can also dramatically inhibit or even stop photosynthesis, stunting algae growth and ultimately the volume of oil produced.

The ability to sustain growth while increasing oil content is an important advance. Algae has other advantages over traditional biofuels because it can grow in salt water and thrive in harsh environmental conditions, therefore limiting stress on food and fresh water supplies.

Oil from algae can also potentially be processed in conventional refineries, producing fuels no different from convenient, energy-dense diesel. Oil produced from algae also holds promise as a potential feedstock for chemical manufacturing.

“The SGI-ExxonMobil science teams have made significant advances over the last several years in efforts to optimize lipid production in algae. This important publication today is evidence of this work, and we remain convinced that synthetic biology holds crucial answers to unlocking the potential of algae as a renewable energy source,” said J. Craig Venter, Ph.D., Synthetic Genomics co-founder and chairman. “We look forward to continued work with ExxonMobil so that eventually we will indeed have a viable alternative energy source.”

Since 2009, ExxonMobil and Synthetic Genomics have been partners in researching and developing oil from algae to be used as a renewable, lower-emission alternative to traditional transportation fuels. Swarup said that while the breakthrough is an important step, the technology is still many years from potentially reaching the commercial market.

“Advancements as potentially important as this require significant time and effort, as is the case with any research and development project,” Swarup said. “Each phase of our algae research, or any other similar project in the area of advanced biofuels, requires testing and analysis to confirm that we’re proceeding down a path toward scale and commercial viability.”

ExxonMobil is engaged in a wide range of research on advanced biofuels, partnering with universities, government laboratories, and other companies. Global demand for transportation-related energy is projected to increase by about 25 percent through 2040, and accelerating the reduction in emissions from the transportation sector will play a critical role in reducing global greenhouse gas emissions.

ExxonMobil is also actively researching other emission-reducing technologies, including carbon capture and sequestration. In 2016, ExxonMobil announced its partnership with Connecticut-based FuelCell Energy, Inc. to advance the use of carbonate fuel cells to economically capture carbon emissions from power plants while generating hydrogen and additional electricity. Since 2000, ExxonMobil has spent about $8 billion to develop and deploy lower-emission energy solutions across its operations. READ MORE and MORE (Biofuels Digest)

Excerpt from Biofuels Digest: But let’s move beyond the cool and towards the fuel. Do we have a path to algae biofuels here — or do we have another technology that’s going to get diverted eventually, via investor exhaustion, to something lovely but much higher up the price curve, such as nutraceuticals?

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But, what if the mechanism that shunts carbon either to protein or lipid production turns out to be genetically subtle and tunable? What if we could find a way to divert the carbon down the lipid-producing pathway, without impacting the delivery of nitrogen for those other critical growth-supporting activities? Steering carbon rather than starving nitrogen?

Turns out, that’s a big part of the SGI / Exxon story.

The technique the researchers used was RNA interference, or RNAi.

In biologyese: In this technique, we target what are known as mRNA molecules, using RBA molecules, and we inhibit gene expression or translation.

In English: If you’ve ever been at a dance with a very good-looking prospective partner and suddenly found yourself completely lost for words — that’s not the same biological process but it’s the same result, the algae lose the ability to do something they really want to do.

What’s great about RNAi is that it works a little bit more like a tunable dial than the knock-in/knock-out techniques used in most applications of CRISPR-Cas9 gene editing.

What do you get?

In the results reported in Nature Biotechnology — you get double the lipid production without a loss of overall productivity, compared to the wild type. It’s not quite the level of lipid production that we’ve seen with Nanno under extreme nitrogen-starvation conditions (55% lipid content has been reported), but the key here is preserving the overall algae growth rate.

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In a techno-economic analysis you can read in glorious detail here, an NREL team found that an algae farm would need to support a minimum selling price of $491 per dry ton of biomass to provide a 10 percent ROI, based on algae productivity of 37 tons per acre. Putting that together, that’s an income goal of $18.167 per acre.

The addressable value

Can we get to algae biofuels, or even close? Right now, algae as a cellulosic fuels commands a values of up to $4.43 per gallon* in the California market, and keep in mind that carbohydrates and protein are also still produced by the organism and are available at harvest.

(*The value is $1.41 for a gallon of any diesel fuel, $2.51 for the cellulosic waiver credit and $0.51 for the California Low Carbon Fuel Standard based on a $52/ton carbon price and a CI index of 29).

At 5 grams per day of lipids (worth $1227 per ton, if you do the cellulosic fuel math), if you could keep the strain producing at this level (which in the field it usually does not) throughout the year (which you won’t be able to), the potential value creation of the improved strain could be as high as $13,323 per acre for the lipid fraction.

So, let’s think more in terms of real-world operation. If we assume that a system could get to 85 percent of this theoretical production rate, and stay open for 80 percent of the year, the value would be on the order of $9060 per acre, for the lipid fraction. (And yes, there’s further bioconversion to turn an algae lipid into a fuel — it’s not entirely “all about the feedstock”.)

And, the venture will need to generate $9,107 per acre off the carbohydrate and protein fractions. We have 7.5 grams per day of those, or 11 tons per acre per year. So, we’d need to see $818 per ton for that biomass. It’s not out of this world to see these kind of numbers — fish meal sells above this price, and fish eat algae.

The Bottom Line

So, let’s be cautiously optimistic. R&D will continue, algae farm CAPEX prices will come down with innovation, yields may well improve from the levels we see here with SGI and Exxon’s work.

Bottom line, we don’t have a production organism here but we are beginning to see the kind of productivities with a defensible strain that support price-competitive algae biofuels at scale, even with the crushingly low oil prices we’re seeing. Rock your world tomorrow? No. In the ballpark of technology that is deployable? Sure. READ MORE and MORE (Science Alert)