(174bc) Metabolic Engineering of K. Marxianus for Improved Polyketide Production

The non-conventional yeast Kluyveromyces marxianus is thermotolerant, acid tolerant, and grows on a wide variety of substrates including glycerol, xylose, and lactose. K. marxianus is also the fastest growing eukaryote known with a growth rate twice that of Baker’s yeast. These attributes make this yeast species an excellent industrial organism. We have previously shown that K. marxianus is a promising heterologous host for the production of polyketides, a class of diverse molecules that are of interest due to their clinical and chemically relevant properties. In our current work, we have used both computational methods and rational pathway analysis to identify several gene modifications to increase flux towards polyketide precursor molecules and to reduce byproduct accumulation in K. marxianus during cultivation on various carbon sources. Using a robust RNA polymerase II driven CRISPR-Cas9 system we developed, multiple gene knockouts, gene additions, and gene upregulation were shown to substantially increase synthesis of two polyketides in this non-conventional yeast species.