Professor Chris Bayliss

Professor of Bacterial Genetics

School/Department: Genetics and Genome Biology, Department of

Telephone: +44 (0)116 252 3465



Professor Bayliss is an expert in bacterial genetics with a specific interest in how hypermutable DNA contributes to the adaptability and spread of bacterial pathogens, and also has an interest in vaccines for preventing bacterial meningitis.

Having being promoted to professor in 2020 within the Department of Genetics and Genome Biology, Professor Bayliss leads a research group comprised of post-doctoral researchers, research assistants and PhD students.

Chris’ long-term interest in microbiology started with completion of a BSc degree in microbiology at Aberystwyth University. This was followed by a PhD at Houghton Poultry Research Institute in Cambridgeshire which involved the cloning and sequencing of the dsRNA genome of infectious bursal disease virus, a pathogen of chickens that led on to two three-year research projects on the molecular biology of vaccinia virus in the Universities of Florida and Oxford.

In 1997, Chris joined Professor Richard Moxon’s team at the Weatherall Institute for Molecular Medicine, Oxford, and worked on hypermutable mechanisms for surface variability in two bacterial pathogens responsible for meningitis.

After seven years Chris moved to the University of Nottingham obtaining a Wellcome Trust Value in People award before joining the Department of Genetics at the University of Leicester, initially as an RCUK research fellow before progressing to lecturer in 2011 and reader in 2016.



Hypermutable DNA sequences enable bacterial pathogens and commensals to colonise and persist in host organisms. A common mechanism involves mutations in tandem DNA repeat tracts (microsatellites). Professor Bayliss’ group focuses on the hypermutable DNA sequences of three bacterial pathogens:

  • Neisseria meningitidis (meningitis and septicaemia)
  • Haemophilus influenzae (meningitis, COPD and otitis media)
  • Campylobacter jejuni (foodborne gastroenteritis)

One key research area is understanding the mutability of these repetitive DNA tracts. Mutations in these repeats switch gene expression ‘on’ and ‘off’ in a process called phase variation. The group uses mutants and reporter constructs to identify cis- and trans-acting factors that control mutability of these tracts.

The group’s other key research area is using bioinformatics molecular biology, epidemiology and modelling to understand how repetitive DNA contributes to host colonisation and disease processes. Their wide range of findings include:

  • Identifying phase-variable genes (the phasome) in genomes of pathogens
  • Observing genetic changes during asymptomatic carriage of meningococci in university students
  • Identifying potential determinants of disease.

Professor Bayliss also has an interest in vaccines for preventing meningitis and uptake of these vaccines by university students.



Professor Bayliss has 86 publications, with five articles in 2020 and eight in 2019.

The publications below highlight recent findings, areas of research, and major outputs.

LR Green, AA Al-Rubaiawi, MARM Al-Maeni, OB Harrison, M Blades, NJ Oldfield and CD Bayliss. Localized hypermutation is the major driver of meningococcal genetic variability during persistent asymptomatic carriage. mBio, 2020, 11(2),

JC Holmes, LR Green, NJ Oldfield, DPJ Turner and CD Bayliss. Rapid transmission of a hyper-virulent meningococcal clone due to high effective contact numbers and super spreaders. Frontiers In Genetics, 2020, 11.

LR Green, N Dave, AB Adewoye, J Lucidarme, SA Clark, NJ Oldfield and CD Bayliss. Potentiation of phase variation in multiple outer-membrane proteins during spread of the hyperinvasive Neisseria meningitidis Serogroup W ST-11 Lineage. Journal of Infectious Diseases, 2019, 220(7), 1109-1117.

CJR Turkington, A Morozov, MRJ Clokie and CD Bayliss. Phage-resistant phase-variant sub-populations mediate herd immunity against bacteriophage invasion of bacterial meta-populations. Frontiers in Microbiology, 2019, 10, 14 pages. 

J Aidley, JJ Wanford, LR Green, SK Sheppard and CD Bayliss. Phasomelt: an 'omics' approach to cataloguing the potential breadth of phase variation in the genus Campylobacter. Microbial Genomics, 2018, 4(11).

CD Bayliss et al. Phase variable genes of Campylobacter jejuni exhibit high mutation rates and specific mutational patterns but mutability is not the major determinant of population structure during host colonisation. Nucleic Acids Research, 2012, 40, 5876-5889.

CD Bayliss. Determinants of phase variation rate and the fitness implications of differing rates for bacterial pathogens. FEMS Microbiol. Rev., 2009, 33: 504-520.


Professor Bayliss’ research group offers several opportunities for postgraduate research at MSc and PhD levels.

Projects focus on the following areas:

  • Phenotypic and genome wide association studies of meningococcal virulence factors
  • Understanding genetic determinants of bacterial gene expression
  • Epidemiological studies of phase variation during meningococcal carriage
  • Understanding the contributions of phase variation to spread and infections by Campylobacter jejuni
  • Genomic analyses of repetitive DNA in bacterial pathogens
  • Computer modelling of phase variation in bacterial populations 


Professor Bayliss’ teaching is focussed on microbial pathogenesis, bacterial genomics and vaccinology. Projects are available to second year summer students, third year undergraduates, and MSc students interested in applying molecular biological and bioinformatics techniques to bacterial research.

Professor Bayliss’ main teaching role is as co-convenor and lecturer of Microbial Pathogenesis and Genomics (BS3011). This module explores in depth the use of molecular biology, infection models and genomics in understanding bacterial pathogens and bacterial virulence factors. Through a series of lectures, tutorials and seminars, the key principles of bacterial pathogenesis are explored alongside learning on critical topics, such as the mechanisms of action of virulence factors, and how to understand original published research.

Professor Bayliss also gives lectures on vaccine development and implementation for bacterial diseases in Advanced Topics in Medical Microbiology (MB3020), and tutors first year students taking Foundations of Biological Sciences and Genes (BS1050).

Professor Bayliss’ post-graduate teaching encompasses general bacterial lectures and an experimental course for the MSc in Molecular Genetics. This experiment provides experience of using sequencing and bioinformatic tools to interrogate bacterial sequences.


Press and media

Professor Bayliss’ research is focused on genetic variability of bacterial pathogens.

Professor Bayliss’ Inaugural Lecture was presented in 2020 and can be viewed here:

Professor Bayliss has an interest in uptake of vaccines by students and associated surveys of COVID-19 vaccine uptake by students has led to the University implementing programs to enhance vaccine uptake:

Professor Bayliss has also been involved in analysis of the functionality of Bexsero, the Meningitis B vaccine that is part of the UK Infant Immunisation Schedule:

Back to top