Postdoctorat; H​/F à l’Institut de Biosciences et Biotechnologies d’Aix-Marseille

Job Title

Microorganism Induced Carbonate Precipitation (MICP) Research Project

The microorganism induced carbonate precipitation (MICP) is a biogeochemical process involving the formation of carbonate crystals in the local environment of metabolically active microorganisms [Hoffmann et al. Microbiology 2021]. Several metabolic pathways can induce the precipitation of carbonate minerals in microorganisms; one of the most studied examples is the enzymatic hydrolysis of urea, which leads to the production of ammonium and carbonate ions and creates favorable conditions for the formation of calcium carbonate crystals.

Extensive precipitation of carbonate minerals in the vicinity of microorganisms in soils can promote the adhesion of sediment particles, thereby reducing porosity and improving the mechanical strength of materials. For these reasons, MICP has become a viable and scalable biotechnology for the reinforcement of soils and structural materials (e.g., concrete, granite). One of the main challenges associated with this technology is the non-uniform distribution of microorganisms and nutrients within heterogeneous porous media, which can lead to inefficient crystallization in the targeted area.

This project aims to improve the homogeneity of bacteria-induced calcium carbonate precipitation in micro- and millifluidic environments, studying the influence of selected biopolymers and medium formulations on the transport of bacteria and nutrients. Fluid layers will be designed to simulate relevant sedimentary grain stacks for MICP studies. Mineral precipitation will be monitored over time under different experimental conditions. The mineral products obtained, prepared from the MICP formulations tested at the beaker scale, will be characterized in terms of structural properties and chemical composition.

This research is part of the international project (ANR-DFG) "OPTIMIC", involving French partners Dr. Dorian Davarzani (BRGM) and Dr. Sophie Sablé (University of La Rochelle), as well as a German partner.

A solid multidisciplinary profile will be an asset for this position. The candidate will hold a PhD with a scientific background in chemistry or material science. Expertise in one or more of the following skills will be considered an advantage: confocal microscopy (Raman, fluorescence), electron microscopy, imaging, X-ray diffraction and spectroscopy, design and use of microfluidic/millifluidic devices, image and video analysis, bacterial culture and manipulation.

The project will be conducted within the Molecular Microbiology and Environment (MEM) team of the Aix-Marseille Biosciences and Biotechnology Institute (BIAM), located in Cadarache, France. BIAM is a mixed research unit involving the CNRS, CEA, and Aix-Marseille University (AMU). The researcher will participate in and lead interdisciplinary laboratory work including bacterial culture, preparation and experimentation of microfluidic devices, imaging, and characterization of mineral products from MICP.

The project will involve measurements in synchrotron radiation facilities as well as visits to partner research groups.

Monthly salary from €3041.58 to €4216.70 gross

44 days of annual leave and sick leave

Travel expenses reimbursement and sustainable mobility allowance up to €300

Offer reference - UMR
7265-SANMAG-001

Section(s) CN / Research area - Cellular Biology, Development, Evolutionary Development

Desired experience - 1 to 4 years

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique multi-specialist position allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.