Salinivibrio sp. EAGSL as a halophilic and ectoine-producing bacteria for broad microbial electrochemistry applications

Salinivibrio sp. EAGSL (S. EAGSL) is an extremophile that was isolated from the Great Salt Lake (UT, USA) in 2017, and this strain has since been the focus of promising research in the field of microbial electrochemistry. Namely, S. EAGSL is an organism with both halotolerance and electroactivity, giving this microbe the unique ability to bridge the gap between power output and halotolerance in microbial fuel cells. While studying the genome, a biosynthetic gene for ectoine was identified. Ectoine is an osmolyte that is deemed a value-added chemical due to its ability to stabilize proteins and other biomolecules in varying conditions, proving its importance for the biochemical and cosmetic industries. Other halophilic bacteria, including Halomonas elongata, have been previously used for industrial production of ectoine. Herein, we evaluate the ectoine production from S. EAGSL, demonstrate proof of concept for S. EAGSL-based microbial fuel cells, and offer discussion for future electrosynthesis applications. [Display omitted] •Biosynthesis of valuable product ectoine is established in novel halophile•Ectoine synthesis in Salinivibrio sp. EAGSL is affected by sodium chloride concentration•Power densities of ∼2 W m−3 are generated in salt-tolerant microbial fuel cells Salinivibrio sp. EAGSL is an electrogenic halophile, recently isolated from the Great Salt Lake in Utah, that synthesizes ectoine. Here, Guynn and Beaver et al. examine how environmental salt concentrations impact ectoine synthesis and create a salt-tolerant microbial fuel cell that could eventually be used for bioenergy, bioremediation, and natural product electrosynthesis.