Post-Doctoral Position in Microbial Ecology M/F

Job Description

Missions

At CNRS-ISTO : Post-Doctoral Position in Microbial Ecology – Study of Iron and Carbon Cycles in Tropical Black Waters (ANR TICAR Project)

The post-doctoral researcher will contribute to the TICAR project by developing an approach combining enzymatic and molecular tracers to study the role of microbial activity in the interactions between the carbon and iron cycles in the source zones of tropical black streams and rivers.

The main objective will be to identify new Fe–C metabolism tracers and characterize the microbial mechanisms involved in the storage or mobilization of iron and carbon, depending on environmental conditions and seasonal variations.

Activity

The post-doctoral researcher will participate in the collection and selection of priority samples (water/sediments) from the different tasks of the TICAR project. They will perform enzymatic analyses to assess microbial activity associated with organic matter degradation. This work will include measuring the activities of β-glucosidase and phenol oxidase using fluorimetric and colorimetric methods adapted to the studied environmental matrices.

The candidate will also implement molecular biology approaches to identify microorganisms involved in iron oxidation and reduction processes. They will carry out the extraction of environmental DNA and RNA, microbial diversity analyses via 16S metabarcoding, and the quantification of functional genes involved in iron redox processes and iron absorption by plants using qPCR. Part of the work will also focus on shotgun metagenomic analysis of selected samples to characterize the overall metabolic potential of microbial communities.

The post-doctoral researcher will participate in the integrated interpretation of the data they generate alongside geochemical and isotopic data, measured in parallel by project partners, to identify new tracers of coupled Fe-carbon metabolism. They will contribute to the scientific valorization of the results through the drafting of reports, scientific publications, and participation in meetings and exchanges with project partners.

These actions will enable:
1. The development of new tracers for the metabolism associated with the coupling of Fe–carbon cycles.
2. The identification of organisms and metabolic functions involved in the storage or release of iron and carbon, depending on environmental conditions.

Your Profil

Skills

The successful candidate must hold a PhD in environmental microbiology. Strong proficiency in enzymatic and molecular microbiological techniques is essential, and experience in one or both of these techniques will be highly valued. The position requires autonomy, rigor, the ability to acquire new techniques, critical thinking, and the capacity to work in an international team at the interface between different disciplines.

Your Work Environment

This position is part of the TICAR project, funded by the French National Research Agency (ANR), which focuses on tracing Iron-Carbon interactions in the source zones of Amazonian Black Rivers. The project studies the role of tropical wetlands, particularly Amazonian black rivers, in the carbon cycle to improve global climate models. The main goal is to better understand the processes of organic matter mineralization, in connection with bacterial activity and iron reduction in these tropical environments.

The Franco-Brazilian consortium of the TICAR project brings together a multidisciplinary team of 35 scientists from the following laboratories in France: GET (Toulouse), ISTO (Orléans), IMPMC (Paris), IPGP (Paris), and Biogéosciences (Dijon), as well as in Brazil: the Department of Geosciences and Geography (Manaus) and the Institute of Geosciences (Brasília). It is also associated with the National Observation Service of the Amazon Basin (HYBAM).

The post-doctoral position will be based at ISTO (Orléans) and will benefit from the microbiology facilities for molecular and microbiological analyses provided by BRGM under institutional agreements (BRGM is one of the supervisory institutions of ISTO, alongside the University of Orléans and CNRS).

Constraints and risks

Developing new tools as markers for the iron cycle, based on genes proposed in the literature for iron cycling, carries risks due to the challenges associated with studying the metabolism of iron-reducing or iron-oxidizing bacteria in situ (in the field). This metabolism is linked to various metabolic strategies related to carbon and nitrogen cycles. However, this information will fill a knowledge gap and provide useful data to complement other approaches, which focus on enzymatic activities, bacterial abundance, iron states, and isotopic compositions.

Additionally, the position is part of an international environment involving numerous academic partners in France and Brazil. The candidate must be willing to participate in meetings, workshops, and international scientific collaborations, particularly during field campaigns in a hot and humid equatorial environment (Amazon rainforest). Some mobility is therefore expected, as well as an interest in interdisciplinary scientific exchanges. A dynamic, open profile capable of quickly integrating into a collaborative network will be particularly appreciated.

Compensation and benefits

Compensation

4395,65 € gross monthly for 7 to 10 years of experience

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

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 position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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