Ashbya gossypii as an alternative cell factory for the valorization of industrial waste and by-product streams

Abstract

Ashbya gossypii is a filamentous hemiascomycete that stands in the intersection between industrial models and nonconventional microorganisms. It has been used for more than 30 years in the industry for the biotechnological production of riboflavin (vitamin B2) and in the last decade the exploration and improvement of this fungus natural metabolism established it as an alternative cell factory for the biotechnological production of other high-added value compounds such recombinant proteins, -lactones, microbial lipids, orotic acid, among others [1-4]. By means of metabolic engineering, improvements have been also accomplished in what concerns the range of substrates used by this fungus [3] and its performance in more challenging cultivation conditions [3-4]. This presentation will address the metabolic and process engineering strategies we used to develop A. gossypii as an alternative cell factory for the de-novo production of: (i) -lactones from glucose-based substrates, (ii) microbial lipids from mixed formulations of corn-cob hydrolysates, sugarcane molasses or crude glycerol, and (iii) orotic acid from crude glycerol. The examples given will demonstrate the biotechnological potential of this fungus towards the recycling and valorization of industrial waste and by-product streams, and aim to contribute to a sustainable and circular bioeconomy.