Photosensitized biohybrid for terminal oxygenation of n-alkane to α, ω-dicarboxylic acids

Abstract

To date, oxyfunctionalization of saturated hydrocarbons in a selective fashion is a prime challenge in industry. Currently, Inorganic-biohybrid catalysts have shown tremendous potential for sustainable conversion of fine chemicals by integrating light harvesting potential of inorganic materials with metabolic activity of microbes. Herein, we have developed a biohybrid system combining a highly efficient light-harvesting inorganic material MoS2-CNT-Eosin-Y and yeast Candida tropicalis (C.tropicalis) for efficient preparation of α, ω- dicarboxylic acid (α, ω-DCA) using saturated n-alkanes. The yeast C.tropicalis harvests photo generated electrons from the illuminated MoS2-CNT-Eosin-Y and uses them for the activation of the P450 catalytic cycle. This process enables the efficient regeneration of nicotinamide cofactors (NADH/NAD+) facilitating production of α, ω-DCA. Under irradiation condition the biohybrid catalyst shows 4.01 times higher dodecanedioic acid production compared to that of native yeast strain. Analysis of NADH/NAD+ ratio and alcohol dehydrogenases (ADH) activity clearly indicates that light illumination on MoS2-CNT-Eosin-Y/C.tropicalis promotes regeneration of cofactor during cellular metabolism of C. tropicalis thereby improving the activity of ADH enzyme resulting higher production of α, ω-DCA. The present work opens up a new avenue for the sustainable synthesis of fine chemicals through tailoring of complex biohybrid pathways.