Co-elicitation of lignocelluloytic enzymatic activities and metabolites production in an Aspergillus-Streptomyces co-culture during lignocellulose fractionation

• Published in: Current research in microbial sciences 2022-01, Vol.3 (100108), p.100108-100108, Article 100108
• Main Authors: Detain, Julian, Rémond, Caroline, Rodrigues, Carine Machado, Harakat, Dominique, Besaury, Ludovic
• Format: Article
• Language: English
• Subjects: CAZymes; Co-culture; Comparative genomics; Environmental Sciences; Lignocellulose; Research Paper; Sreptomyces
• ISSN: 2666-5174; 2666-5174
• DOI: 10.1016/j.crmicr.2022.100108

•An easy set-up of the co-cultures from 2 different microorganisms (filamentous fungi and bacteria) from different microbial domains resulting into a greater and more diverse metabolic and lignocellulolytic content.•An over expression of several key enzymatic lignocellulolytic activities is observed during the co-coculture due to elicitation.•An elicitation of some specific biosynthetic cluster genes is observed due to the activation of those the complexity of the carbon compounds present in the lignocellulose.•An elicitation of some specific biosynthetic cluster genes is observed only during the co-culture experiment.•A specific microbial crosstalk and interaction exists at the species level between the 3 Streptomyces and the fungi leading to a specific of lignocellulolytic enzyme and secondary metabolite production. Lignocellulose, the most abundant biomass on Earth, is a complex recalcitrant material mainly composed of three fractions: cellulose, hemicelluloses and lignins. In nature, lignocellulose is efficiently degraded for carbon recycling. Lignocellulose degradation involves numerous microorganisms and their secreted enzymes that act in synergy. Even they are efficient, the natural processes for lignocellulose degradation are slow (weeks to months). In this study, the objective was to study the synergism of some microorganisms to achieve efficient and rapid lignocellulose degradation. Wheat bran, an abundant co-product from milling industry, was selected as lignocellulosic biomass. Mono-cultures and co-cultures involving one A.niger strain fungi never sequenced before (DSM 1957) and either one of three different Streptomyces strains were tested in order to investigate the potentiality for efficient lignocellulose degradability. Comparative genomics of the strain Aspergillus niger DSM 1957 revealed that it harboured the maximum of AA, CBM, CE and GH among its closest relative strains. The different co-cultures set-up enriched the metabolic diversity and the lignocellulolytic CAZyme content. Depending on the co-cultures, an over-expression of some enzymatic activities (xylanase, glucosidase, arabinosidase) was observed in the co-cultures compared to the mono-cultures suggesting a specific microbial cross-talk depending on the microbial partner. Moreover, metabolomics for each mono and co-culture was performed and revealed an elicitation of the production of secondary metabolites and the activation of silent biosynthetic cluster genes depending on the