Rizlan Bernier-Latmani

Biography

HIGHER EDUCATION

Summer course: Advances in Genome Technology and Bioinformatics Course at the Marine Biology Laboratory in Woods Hole, MA. October 2005.

Ph.D. 2001 Civil and Environmental Engineering, Stanford University, CA

(Advisor, Jim Leckie, Biodegradation of uranyl (UO22 )-complexed citrate and implications for uranyl mobility in the subsurface)

M.S. 1995 Civil and Environmental Engineering, Stanford University, CA

B.S. 1993 Natural Resources with Honors, Cornell University, Ithaca, NY

PROFESSIONAL EMPLOYMENT

2013-present Associate professor with tenure, School of Architecture, Civil and Environmental Engineering, Swiss Federal Institute of Technology, Lausanne

2005-2013 Assistant professor tenure track, School of Architecture, Civil and Environmental Engineering, Swiss Federal Institute of Technology, Lausanne

2001-2005 Post-Graduate Researcher, Scripps Institution of Oceanography, La Jolla, CA (PI: Brad Tebo)

1995-2001 Graduate Research Assistant, Stanford University (Advisor: Jim Leckie)

RESEARCH INTERESTS

Gemicrobiology, metal-bacteria interactions, biological reduction and oxidation of metals, biological nanoparticle formation; Characterization of microbial communities in terrestrial environments; Using genomic, microscopic and spectroscopic tools to understand metal transformations by microorganisms.

ACADEMIC HONORS

Rotary Foundation University Professor grant, 2004.

Swiss National Science Foundation Post-doctoral Fellowship, 2001.

Leon B. Reynolds Memorial Scholarship in the School of Engineering at Stanford University, 1995-96.

Graduated with Honors from Cornell University, 1993.

BIBLIOMETRY

http://www.researcherid.com/rid/E-4398-2011

ResearcherID: E-4398-2011

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related units (7)

Related units

Courses taught by this person (2)

Courses taught by this person

Related research domains (96)

Related research domains

Related publications (140)

Related publications

People doing similar research (105)

People doing similar research

Related publications (140)

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

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

2023

, , , ,

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(VI) complexes for bacteria such as Shewanella oneidensis MR-1. Recent studies have onfirmed that the reduction proceeds via a first electron transfer forming pentavalent U(V) species that readily disproportionates. However, in the presence of the stabilizing aminocarboxylate ligand, dpaea2− (dpaeaH2bis(pyridyl-6-methyl-2-carboxylate)-ethylamine), biologically produced U(V) persisted in aqueous solution at pH 7. We aim to pinpoint the role of MHC in the reduction of U(V)-dpaea and to establish the mechanism of solid-phase U(VI)-dpaea reduction. To that end, we investigated U-dpaea reduction by two deletion mutants of S. oneidensis MR-1−one lacking outer membrane MHCs and the other lacking all outer membrane MHCs and a transmembrane MHC−and by the purified outer membrane MHC, MtrC. Our results suggest that solid-phase U(VI)-dpaea is reduced primarily by outer membrane MHCs. Additionally, MtrC can directly transfer electrons to U(V)-dpaea to form U(IV) species but is not strictly necessary, underscoring the primary involvement of outer membrane MHCs in the reduction of this pentavalent U species but not excluding that of periplasmic MHCs.

2023

Spatially Explicit Linkages Between Redox Potential Cycles and Soil Moisture Fluctuations

Mitra Asadollahi, Paolo Benettin, Rizlan Bernier-Latmani, Manon Frutschi, Filippo Miele, Andrea Rinaldo, Simiao Wang

Reduction-oxidation cycles measured through soil redox potential (Eh) are associated with dynamic soil microbial activity. Understanding changes in the composition of, and resource use by, soil microbial communities requires Eh predictability under shifting hydrologic drivers. Here, 50-cm soil column installations are manipulated to vary hydrologic and geochemical conditions, and are extensively monitored by a dense instrumental deployment to record the depth-time variation of physical and biogeochemical conditions. We contrast measurements of Eh, soil saturation and key compounds in water samples (probing the majority of soil microbial metabolisms) with computations of the relevant state variables, to investigate the interplay between soil moisture and redox potential dynamics. Our results highlight the importance of joint spatially resolved hydrologic flow/transport and redox processes, the worth of contrasting experiments and computations for a sufficient understanding of the Eh dynamics, and the minimum amount of biogeochemistry needed to characterize the dynamics of electron donors/acceptors that are responsible for the patterns of Eh not directly explained by physical oxic/anoxic transitions. As an example, measured concentrations of sulfate, ammonium and iron II suggest coexistence of both oxic and anoxic conditions. We find that the local saturation velocity (a threshold value of the time derivative of soil saturation) exerts a significant hysteretic control on oxygen intrusion and on the cycling of redox potentials, in contrast with approaches using a single threshold saturation level as the determinant of anoxic conditions. Our findings improve our ability to target how and where hotspots of activity develop within soil microbial communities.

2023