Job offer

Avignon Université; Marseille; Sur place; EUR 30 000 - 40 000; Plein temps

Résumé du poste

Une entreprise de recherche dynamique cherche un candidat passionné par la biologie des plantes et la chimie pour un projet de thèse innovant. Le candidat travaillera sur l'impact des éclairs de lumière UV-C sur le stress oxydatif et explorera des méthodes d'extraction pour des molécules d'intérêt. Ce projet offre une occasion unique de contribuer à des recherches de pointe dans le domaine des sciences environnementales, tout en développant des compétences pratiques dans des outils avancés. Rejoignez une équipe engagée dans la recherche et l'innovation, où vos contributions auront un impact significatif sur la compréhension des mécanismes de défense des plantes.

Qualifications

• Bonne connaissance de la chimie ou biochimie, ouverture à la biologie des plantes.
• Capacité à développer des compétences dans différents outils et à rédiger.

Responsabilités

• Caractériser le stress oxydatif généré par les éclairs de lumière UV-C.
• Identifier les molécules d'intérêt pour stimuler le priming.

Connaissances

Chimie

Biologie des plantes

Développement de compétences

Rédaction

Formation

Doctorat en sciences environnementales

Outils

Systèmes de mesure de fluorescence chlorophyllienne

EPR couplé avec piégeage de spin

Plateforme de métabolomique de l'Université d'Avignon

Techniques d'extraction et de préparation de formulations stables

Équipement de caractérisation d'émulsions

Description du poste

Organisation/Company: Avignon Université

Research Field: Environmental science » Ecology

Researcher Profile: Recognised Researcher (R2), Leading Researcher (R4), First Stage Researcher (R1), Established Researcher (R3)

Country: France

Application Deadline: 21 May 2025 - 22:00 (UTC)

Type of Contract: Temporary

Job Status: Full-time

Is the job funded through the EU Research Framework Programme? Not funded by a EU programme

Is the Job related to staff position within a Research Infrastructure? No

Offer Description

In plants, UV-C light flashes have a powerful priming effect on abiotic stress tolerance and disease defense mechanisms.

Our measurements and the literature indicate that UV-C light flashes cause oxidative stress, which we hypothesize plays a decisive role upstream of the signalling pathways that lead to priming. This oxidative stress has never been characterized either quantitatively or qualitatively.

The aims of this thesis project are to:

1. Characterize the oxidative stress generated by UV-C light flashes using chlorophyll fluorescence tools (hypothesis of a major role for UV-C light absorption by the photosynthetic machinery), Electron paramagnetic Resonance (EPR), analytical chemistry tools, etc.
2. Identify, among the targets of UV-C light flashes, molecules that could be used to stimulate priming. The possibility of synthesizing analogues is being considered.
3. Develop non-destructive extraction and formulation methods for the previously identified molecules of interest, and study the efficiency and kinetics of their phytoprotective effects.

Tools:

1. Chlorophyll fluorescence measurement systems;
2. EPR coupled with spin trapping;
3. Avignon University metabolomics platform;
4. Techniques and tools for extraction and preparation of stable formulations;
5. Emulsion characterization equipment.

Method:

The first phase of the thesis will be devoted to characterizing the effects of UV-C light flashes on various markers of oxidative stress in Arabidopsis thaliana L., including physiological and biochemical markers.

Nitrone-type probes will be used to trap oxygenated and/or carbonated radical species and detect them by EPR. Nitroxide/hydroxylamine probes will also be used to monitor the redox status of the medium under study.

The second phase of the thesis will aim to further develop the main hypotheses generated during the first phase of the thesis. From a practical point of view, the second phase aims to identify molecules of interest involved in the stress priming triggered by UV-C light flashes and the associated oxidative stress.

The third phase of the thesis will aim to develop extraction and formulation methods for the molecules of interest identified at the end of the first two phases (markers), and, if possible, to test their effects.

Skills expected of the candidate:

• Good knowledge of chemistry or biochemistry;
• Openness to plant biology;
• Ability to develop skills in different tools;
• Ability to write.

Début de la thèse: 01/10/2025

Funding category: Contrat doctoral