UW-Madison researchers found that Novo naturally produces the carotenoid nostoxanthin, which accumulates in its cells. Further, predicted nostoxanthin intermediates include a number of valuable carotenoids, so they began to look for mutations (gene deletions) that would cause Novo to accumulate one of β-carotene, lycopene, or zeaxanthin, instead of nostoxanthin. Once identified, a series of knock out Novo mutants were created and tested on a variety of substrates (e.g., pure aromatics purchase from Sigma and in liquor derived from alkaline pretreated sorghum biomass (sorghum APL)) with each successfully accumulating the desired carotenoid intracellularly. Further, the inventors constructed Novo strains that were capable of producing zeaxanthin, β-carotene, or astaxanthin concurrently with 2-pyrone-4,6-dicarboxylic acid (PDC), a potential building block for biodegradable polymers.