PhD in Experimental Microbial Ecology (deadline extended)

About the project

This PhD project will develop controlled experimental systems to investigate top-down and bottom-up ecological strategies that directly shape the biosignatures of sulfur-cycling bacteria in low-oxygen environments. The main focus will be on virus–host interactions in purple (PSB) and green (GSB) sulfur bacteria related to the microbial anoxic communities of meromictic Lake Cadagno. The work will combine laboratory-based experiments at the University of Lausanne (UNIL) and at Scuola universitaria professionale della Svizzera italiana (SUPSI, Mendrisio) with field observations in stratified aquatic environments (e.g., meromictic lakes), particularly during June-October.

The candidate will generate the empirical foundation needed to quantify how viral perturbations affect microbial metabolism and biogeochemical outputs.

Job information

Expected start date in position : fall 2026 or upon agreement

Contract length : 4 years (1+2+1)

Activity rate : 100%                     

Workplace : Géopolis building, Institute of Earth Sciences, Faculty of Geosciences and Environment, University of Lausanne

Responsibilities and qualifications

The successful candidate will investigate virus–host interactions in anoxygenic phototrophic sulfur bacteria through a combination of field, laboratory, and molecular approaches. The project will involve monitoring and isolating viruses from natural environments, performing infection experiments with different anoxygenic phototrophic sulfur bacteria, and conducting anaerobic microbiology experiments under controlled redox conditions using systems such as microfluidics and mesocosms. The candidate will characterize microbial responses using flow cytometry, viability assays (e.g., live/dead staining), microscopy, and spatial analyses, while developing molecular workflows including qPCR quantification, RNA extraction, and transcriptomic sample preparation. The position also includes organizing and participating in field monitoring campaigns at Lake Cadagno (Ticino, Switzerland) and working closely with computational collaborators to integrate experimental and multi-omics data into a comprehensive understanding of virus-driven microbial processes.

We are looking for a motivated candidate with a strong interest in environmental microbiology and geomicrobiology. A master’s (or equivalent) degree in microbiology, environmental sciences, biology, or a related field is preferred. We encourage candidates with an interest in microbial ecology and biogeochemistry and a motivation for fieldwork in lake environments to apply.

Application

The application can only be officially sent through here, and should include:

  • Your CV including academic background, previous research/publications and/or industrial experiences as well as the names and contact details of 2-3 referees
  • A cover letter outlining your research motivation and interests (max. 1 page)
  • Copy of your diplomas

The application deadline is August 20th, 2026.

Contact information: alice.boscosantos@unil.ch