Great Lakes Bioenergy Research Center  researchers produce engineered strains of valuable carotenoids

In Wisconsin, scientists with the Great Lakes Bioenergy Research Center showed that a strain of Novosphingobium aromaticivorans naturally produces the carotenoid nostoxanthin. By deleting or adding selected genes, they engineered strains that produced the valuable carotenoids beta-carotene, lycopene, zeaxanthin, and astaxanthin. They showed that these engineered strains produced carotenoids at comparable levels when grown either in laboratory media or in alkaline-pretreated sorghum biomass, which contains a mixture of aromatics.

Finally, they engineered strains that when grown on sorghum liquor produced zeaxanthin, beta-carotene, or astaxanthin concurrently with 2-pyrone-4,6-dicarboxylic acid (PDC), a potential building block for biodegradable polymers. Combined, the results show that N. aromaticivorans can simultaneously produce valuable intracellular and extracellular commodities when grown in the presence of either pure aromatics or pretreated lignocellulosic biomass.