Available Technology
Sugar production from photosynthetic bacteria
Technology:
Secreted bioproducts from photosynthetic microbes
Markets Addressed
The need for biofuels is becoming more urgent with the increase in global warming, decreasing availability of easily accessed petroleum, and the rise of former third-world countries with an immense demand for oil. Many systems for production of biofuels involve the metabolic conversion of carbohydrates into fuel, resulting in increased demand for carbohydrates such as sugars. Researchers at the Wyss Institute have developed a photosynthetic bacterium that directs much of its metabolic output into the synthesis and secretion of sucrose, or table sugar. This bacterium should enable the production of sugar in colder climates where sugarcane cannot be grown, such as most of the US.
The world-wide market for sugar is approximately $60 billion. Significant growth in US demand is expected over the next decade due to government mandates for biofuel use (the National Renewable Fuel Standard). Currently, the primary biofuel in the US is ethanol generated by fermentation of sugars derived from corn. Attempts to convert cellulosic biomass into biofuels have met with serious technical problems. Outside the US, sugar is primarily produced from sugarcane, which can only be grown in tropical climates, so that a limited number of countries such as Brazil dominate sugar production. While the food market for sugar is relatively flat, the increased demand for biofuels will accelerate the demand for carbohydrates.
The US market for sugar. New governmental mandates (the National Renewable Fuel Standard) are expected to increase the demand for sugar that can be processed into biofuels (Sources: EPA web site, document EPA-420-F-09-023; “Sugar Backgrounder”, USDA document SSS-249-01; and MIT Energy Club Units & Coversions Fact Sheet.)
Innovations and Advantages
Cyanobacteria are photosynthetic bacteria that use the same biochemical systems as green plants for capturing light energy and fixing CO2. These bacteria grow quite rapidly in comparison to plants, doubling in mass every ~12-24 hours. Their only nutrients are sunlight, CO2, water, and minerals. These bacteria respond by producing internal sucrose in response to certain environmental conditions.
To harness this phenomenon for large-scale carbohydrate production, we engineered a novel photosynthetic bacterium to produce and secrete high levels of sucrose – in initial experiments, about 50% of the energy that is normally devoted to producing more bacterial biomass is now directed into sugar production. Moreover, because the sucrose is secreted, continuous harvesting of the product is possible.
Production of sucrose from engineered photosynthetic bacteria. When production is induced in the engineered strain, about 50% of the energy captured from photons is directed into sucrose synthesis. Overall productivity of the system is also increased.
Additional Information
Intellectual Property Status: Patent(s) pending
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Inventor(s):
Niederholtmeyer, Henrike Marie
Savage, David F.
Way, Jeffrey Charles
Wolfstaedter, Bernd
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For further information, please contact:
Laura Brass, Director of Business Development
(617) 495-3067
Reference Harvard Case #3763