Adaptive evolution of Bacillus subtilis for biosurfactant production

Abstract

Surfactins are surfactants available by microorganisms that associate effective activity with low toxicity and high biodegradability. Compounds like this type are of great industrial interest, especially in the field of green chemistry. The green chemical industry has grown in line with the increase in responsibilities related to the environmental impacts of human actions. However, the productivity of natural strains of Bacillus subtilis, surfactin-producing bacteria, is insufficient for the economic viability of industrial production. And even as the production optimization process has not been enough to reach the levels according to the requirements. As genetic approaches are required but do not hinder the microorganism's susceptibility to the biosurfactant that ends up being toxic to cells when a threshold is reached. In this context, this project proposes the use of the adaptative evolution technique of B. subtilis for biosurfactant production. A strain previously modified by rational design will be exposed to different surfactin concentrations, and mutants with potential for resistance will be sequenced, analyzed, and genetically characterized by bioinformatics tools. The mutations will be reproduced by rational design, through CRISPR-Cas9 genetic editing, specific to the construction of a bacterial chassis more resistant to surfactin. The modifications proposed in this project have an innovative character, intending to make the production of surfactin more industrially viable and connect with two other promising projects for production optimization.