Freie Stellen / Dissertationen

Open PhD student position on the molecular basis of Listeria monocytogenes stress resilience mechanisms involved in survival along the human food supply

We invite applicants for an open PhD student position at the Institute for Food Safety and Hygiene, Vetsuisse Faculty, University of Zurich. Area of study for this PhD is in molecular microbial food safety and hygiene. More specifically molecular stress resilience mechanisms underlying the survival and growth of Listeria monocytogenes exposed to food hygiene and preservation environmental conditions along the human food supply chain will be investigated. The incumbent candidate will join an active research group within a lab that broadly works on microbial food safety and hygiene issues investigating molecular epidemiology and stress resistance mechanisms of different foodborne pathogens using a wide range of experimental approaches and techniques, and state of the art lab facilities.

Background: L. monocytogenes is responsible for serious public health and food safety problems. A cause of listeriosis this pathogen is responsible for one of most serious foodborne diseases accounting for high rates of hospitalisation and mortality in susceptible people with reduced immunity such as the young, pregnant, old and immunocompromised individuals. Current efforts to control L. monocytogenes along the human food supply chain are challenged due to widespread occurrence and possession of robust stress resilience molecular mechanisms enabling survival and growth even under harsh environmental conditions applied for foodborne pathogen control including biocides, low temperatures, elevated salt levels, low pH and inclusion of antimicrobial peptides. Our lab investigates molecular mechanisms that are employed by L. monocytogenes for stress survival and adaptation along the farm to table continuum. Applying microbiological and molecular biology techniques as well as bioinformatics this PhD project will investigate stress response mechanisms deployed by L. monocytogenes in order to survive exposure to natural organic antimicrobial compounds (e.g. nisin) that are being used or being developed for control of foodborne bacterial pathogens. We are motivated to improve current knowledge and understanding of these aspects in L. monocytogenes for the purposes of devising improved mitigation strategies against this pathogen.

Responsibilities and Tasks: In this PhD project genomics and different molecular approaches will be used to characterise molecular mechanisms underlying L. monocytogenes resistance to natural organic antimicrobials. Using comparative genomics and transcriptomics genes involved resistance to natural antimicrobials nisin and -phenylethylamine will be identified and functionally characterised through gene expression, deletion mutagenesis and phenotypic analysis of the mutants. Qualifications You must be a highly motivated individual with relevant background and experience in food safety and microbiology.

Candidates with a first degree or a masters in veterinary medicine, microbiology, food science or related disciplines are encouraged to apply. Previous experience in microbial culture techniques, molecular methods such as nucleic acid extraction, PCR, as well as protocol trouble-shooting and basic bioinformatics will be considered an asset but it’s not a requirement.

Approval and Enrolment: The PhD position is subjected to academic approval, and the candidates will be enrolled in the PhD degree programmes of the Universities of Zurich (MIM PhD programme; or Bern (GCB PhD programme;


Application Applicants should submit their application to PD Dr. Taurai Tasara ( Potential applicants will continue to be accepted until the position is filled. The application should include: • Cover letter stating your specific interest, motivation and qualifications for the project. • Curriculum vitae including relevant information about previous employment, research training, experience and competencies, teaching experience, scientific publications, conference presentations and a list of personal references.


S. auch Stellenbörse der Universität Zürich.