Publications de Margaux Camille Andréa Molinas

Speciation-dependent molecular mechanism of electron transfer from the c-type cytochrome MtrC to U(VI)-ligand complexes

Rizlan Bernier-Latmani, Luciano Andres Abriata, Karin Lederballe Meibom, Margaux Camille Andréa Molinas

Members of the Shewanella genus transfer electrons to metal and actinide electron acceptors such as hexavalent uranium, U(VI), via c-type cytochromes. The intracellular mechanism of electron transfer is well studied but the delivery of electrons to externa ...

2025

The isotopic signature of U(V) during bacterial reduction

Marinella Mazzanti, Rizlan Bernier-Latmani, Margaux Camille Andréa Molinas, Radmila Faizova, Ashley Richards Brown

The two-step electron transfer during bacterial reduction of UVI to UIV is typically accompanied by mass-independent fractionation of the 238U and 235U isotopes, whereby the heavy isotope accumulates in the reduced product. However, the role of the UV inte ...

2024

Electron flux is a key determinant of uranium isotope fractionation during bacterial reduction

Rizlan Bernier-Latmani, Margaux Camille Andréa Molinas, Ashley Richards Brown

Uranium isotopic signatures in the rock record are utilized as a proxy for past redox conditions on Earth. However, these signatures display significant variability that complicates the interpretation of specific redox conditions. Using the model uranium-r ...

2023

Mechanism of Reduction of Aqueous U(V)-dpaea and Solid-Phase U(VI)-dpaea Complexes: The Role of Multiheme c-Type Cytochromes

Marinella Mazzanti, Rizlan Bernier-Latmani, Karin Lederballe Meibom, Margaux Camille Andréa Molinas, Radmila Faizova

The biological reduction of soluble U(VI) complexes to form immobile U(IV) species has been proposed to remediate contaminated sites. It is well established that multiheme c-type cytochromes (MHCs) are key mediators of electron transfer to aqueous phase U( ...

2023

Insights into the microbial reduction of pentavalent and hexavalent uranium species by Shewanella oneidensis MR-1

Margaux Camille Andréa Molinas

Decades of uranium-related activities such as ore mining, nuclear power generation, weapon manufacture, storage of nuclear wastes, have contributed to the release of U in the environment. U occurrence is concerning, since in surface environments, U is typi ...

EPFL2021

Biological reduction of a U(V)-organic ligand complex

Margaux Camille Andréa Molinas, Radmila Faizova, Ashley Richards Brown

Metal-reducing microorganisms such as Shewanella oneidensis MR-1 reduce highly soluble species of hexavalent uranyl (U(VI)) to less mobile tetravalent uranium (U(IV)) compounds. The biologically mediated immobilization of U(VI) is being considered for the ...

2021