Abstract
AbstractBackgroundBacillus subtilishas been established as model microorganism for fundamental research in the laboratory on protein production/secretion and sporulation and as model bacterium for controlling spoilage in the food industry. It has also been used for production of (commercial) enzymes and several secondary metabolites such as vitamins. However, this doesn’t fully reflect the potential ofB. subtilisas a cell-factory. Here, various strains ofB. subtilis, including food-grade, spore-deficient strains and industrially used strains, were compared for their growth and metabolic potential. Industry-relevant parameters were analyzed for all strains under various aeration regimes, under anaerobic conditions, in various nutritious and nutrient-limited cultivation media, with and without organic nitrogen sources, and with and without sugar.ResultsPractical experiments were conducted to compare industrial relevant properties like growth rates, intracellular components and extracellular metabolite profile of differentB. subtilisstrains. Based on growth flexibility in different media, we found that some strains like NCIB3610 and DSM1092 are adapted to inorganic or organic nitrogen source utilization, which is highly relevant when considering a biorefinery approach using various cheap and abundant waste/sidestreams. Secondly, spore-deficient strains such as 3NA, 168S and PY79S, showed advantages in microbial protein and acetolactate pathway expression, which is associated with applications in food industry for protein supplement and diacetyl production. Lastly, WB800 and PY79S exhibited potential for fermentative production of Dipicolinic acid, 2,3-Butanediol and Lactic acid that could serve as precursors for biopolymers.ConclusionThis study demonstrates the broad potential for more extensive industrial use ofBacillus subtilisin the (bio-based) chemical industry for use of sidestreams, in the personal care industry, in the food industry for food additive production, and in the bio-sustainable industry for biofuel and bio-degradable plastic precursors production. In addition, selecting differentB. subtilisstrains for specific purposes makes full use of the diversity of this species and increases the potential ofB. subtilisin its contribution to the bio-based economy.
Publisher
Cold Spring Harbor Laboratory