Genetic Evidences of Biosurfactant Production in Two Bacillus subtilis Strains MB415 and MB418 Isolated From Oil Contaminated Soil

Abstract

Biosurfactants are a diverse group of amphiphilic compounds obtained from microbes. In the present study, the genomic analysis of biosurfactant-producing Bacillus subtilis MB415 and MB418 obtained from oil-contaminated soil was performed. Initially, the strains were screened for biosurfactant production by hemolytic assay, emulsification index, and oil displacement. Further FTIR analysis of extracted biosurfactants revealed the presence of lipopeptides. The sequenced genomes of MB415 and MB418 were of 4.2 Mbps with 43% GC content. Among more than 4,500 protein-coding genes, many were involved in virulence, metal/multidrug resistances, flagella assembly, chemotactic response, and aromatic ring hydroxylating dioxygenases. An annotation analysis revealed that both genomes possessed non-ribosomal synthetase gene clusters for the lipopeptide synthetases srf and fen responsible for surfactin and fengycin production. Comparative studies of both genomes highlighted variability in gene operons mainly for surfactin biosynthesis.

Biosurfactants as templates to inspire new environmental and health applications

“…Likewise, Bacillus amyloliquefaciens An6 produces a biosurfactant with low toxicity that decreased the interfacial tension between diesel oil and water, enhancing bioavailability of diesel oil for degradation and making it a useful tool for bioremediation (Ben Ayed et al, 2015). Investigations of highly polluted soil continually reveal bacterial and fungal species that exhibit biosurfactant production (Singh and Cameotra, 2013;Janek et al, 2021;Yasmin et al, 2022), perhaps as a potential survival mechanism amongst hydrocarbon and heavy metal pollutants. Here, the evolution and adaptations of microbes for the natural production of biosurfactants may serve as a foundation for directed evolution or rationale-based design of improved or novel biosurfactants.…”