Jürgensen, NikolaiNikolaiJürgensenWeiler, JanekJanekWeilerKnoll, Melanie TabeaMelanie TabeaKnollGescher, JohannesJohannesGescherEdel, MiriamMiriamEdel2025-01-072025-01-072024-11-28New Biotechnology 85: 31-38 (2025-03-25)https://tore.tuhh.de/handle/11420/52786Microbial electrochemical systems offer a sustainable method for the conversion of chemical energy into electrical energy or hydrogen and the production of valuable compounds, contributing to the development of a bio-based economy. This study aimed to enhance the performance of anodic bioelectrochemical systems by improving the current density of Shewanella oneidensis as a biocatalyst through strain modification and medium refinement. The genetic modification, combining the prophage deletion and overexpression of the speC gene, resulted in a 4.2-fold increase in current density compared to the wild type. Furthermore, medium refinement and incorporating riboflavin, led to an additional 5.7-fold increase in current density. The application of the modified strain and medium in a scalable microbial electrolysis cell resulted in a current density of 1.2 A m-², similar to what was achieved previously with an S. oneidensis and Geobacter sulfurreducens co-culture, substantiating the substantial performance increase for a pure culture of S. oneidensis. Furthermore, S. oneidensis was shown to grow in medium containing up to 500 mM sodium chloride and increasing the salt concentration to 400 mM had a minor influence on growth but significantly lowered the cell voltage of the MEC system.en1871-678420243138Elsevierhttps://creativecommons.org/licenses/by-nc-nd/4.0/Bioelectrochemical system | Current density | Microbial electrolysis cell | Scale-up | Shewanella oneidensisTechnology::660: Chemistry; Chemical Engineering::660.6: BiotechnologyJournal Articlehttps://doi.org/10.15480/882.14159https://doi.org/10.15480/882.1415910.1016/j.nbt.2024.11.00610.15480/882.1415910.15480/882.14159Journal Article