PhD position - Microbiology: Ireland

University College Dublin invites applications for a fully funded PhD position on a project: “An Investigation of Antibiotic Resistance and Biofilm Formation in Campylobacter jejuni”.

Campylobacter jejuni is the leading cause of bacterial gastroenteritis and infects millions of people worldwide. C. jejuni has recently been listed by the World Health Organisation as one of 12 organisms that are priority pathogens due to an increase in isolates resistant to antibiotics (WHO 2017). Although the organism is severely pathogenic in humans it appears to function as a commensal in chickens and a study in 2010 by the European Food Safety Authority revealed that 98% of Irish supermarket chickens are contaminated with this pathogen (EFSA 2010). The difference in behaviour in chickens and humans suggests the organism has the ability to regulate virulence depending on the host it encounters.
Recent papers from the Ó Cróinín group have revealed the key role played by DNA Supercoiling in regulating Motility (Shortt et al 2016) and Invasion (Scanlan et al 2017). Furthermore Fluoroquinolone resistance in C. jejuni is known to be associated with altered levels of DNA supercoiling. The aim of this project is to investigate the relationship between antibiotic resistance and biofilm formation as well as other phenotypes to ascertain whether antibiotic resistant strains may have phenotypes which benefit their survival in different ecological niches. The project will involve a broad range of techniques ranging from molecular biology to cell culture and including a variety of in vitro assays.

The successful candidate should have a 1st or upper 2nd Class Honours degree in Microbiology, Biochemistry, Genetics or a related subject and should be highly motivated. Informal enquiries should be directed to

  1. Shortt C, Scanlan E, Hilliard A, Cotroneo CE, Bourke B, Ó Cróinín T. (2016) ‘DNA Supercoiling Regulates the Motility of Campylobacter jejuni and Is Altered by Growth in the Presence of Chicken Mucus’. mBio, 13 (5):e01227-16-e01227-16.
  2. Scanlan E, Ardill L, Whelan MVX, Shortt C, Nally JE, Bourke B and Ó Cróinín T (2017) ‘Relaxation of DNA Supercoiling leads to increased invasion of epithelial cells and protein secretion by Campylobacter jejuni’. Molecular Microbiology, 104 (1):92-104.

Enquiries and applications (to include cover letter and CV) to Dr Tadhg Ó Cróinín. Email:

Further details
Share this opportunity