Identification of a multi-modal mechanism for Se(VI) reduction and Se(0) allotropic transition by Stenotrophomonas bentonitica Ruiz Fresneda, Miguel Ángel Lazuén López, Guillermo Pérez-Muelas, Eduardo Peña Martín, Jesús Linares-Jiménez, Raúl Eduardo Newman Portela, Antonio Martín Merroun, Mohamed Larbi Selenate Bioremediation Multi-modal Reduction Thioredoxin Flagellin Funding for open access publishing: Universidad de Granada/CBUA. This work was supported by grant TED2021.131099B.I00 awarded by the Spanish Ministry of Science and Innovation to M. L. M. The research presented in this article has also received funding from the RADONORM project of the Euratom research and training programme 2019–2020 (grant agreement number 900009). Microorganisms can play a key role in selenium (Se) bioremediation and the fabrication of Se-based nanomaterials by reducing toxic forms (Se(VI) and Se(IV)) into Se(0). In recent years, omics have become a useful tool in understanding the metabolic pathways involved in the reduction process. This paper aims to elucidate the specific molecular mechanisms involved in Se(VI) reduction by the bacterium Stenotrophomonas bentonitica. Both cytoplasmic and membrane fractions were able to reduce Se(VI) to Se(0) nanoparticles (NPs) with different morphologies (nanospheres and nanorods) and allo- tropes (amorphous, monoclinic, and trigonal). Proteomic analyses indicated an adaptive response against Se(VI) through the alteration of several metabolic pathways including those related to energy acquisition, synthesis of proteins and nucleic acids, and transport systems. Whilst the thioredoxin system and the Painter reactions were identified to play a crucial role in Se reduction, flagellin may also be involved in the allotropic transformation of Se. These findings suggest a multi-modal reduction mechanism is involved, providing new insights for developing novel strategies in bioremediation and nanoparticle synthesis for the recovery of critical materials within the concept of circular economy. 2024-07-12T11:44:58Z 2024-07-12T11:44:58Z 2024-07-12 journal article Ruiz-Fresneda, M.A., Lazúen-López, G., Pérez-Muelas, E. et al. Identification of a multi-modal mechanism for Se(VI) reduction and Se(0) allotropic transition by Stenotrophomonas bentonitica. Environ Sci Pollut Res (2024). https://doi.org/10.1007/s11356-024-34256-z https://hdl.handle.net/10481/93097 eng http://creativecommons.org/licenses/by-nc-nd/3.0/ open access Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License Springer Nature