I have extensive experience in bacterial physiology and biochemistry, including bacterial protein phosphorylation (I was the first to identify tyrosine phosphorylation as a regulatory mechanism in bacteria and provided key evidence concerning the biochemical function of the Universal Stress protein (uspA) in E. coli). Currently, my research interests are focused on the relationship between stress and infection. I am a co-founder and internationally recognised leader in the field of Microbial Endocrinology, a newly recognised research discipline which represents the intersection of microbiology, endocrinology and neurophysiology. Microbial Endocrinology is directed at providing a new framework with which to examine and understand the ability of microorganisms to interact with a host in both health and disease (Freestone et al 2008, Trends in Microbiology). My Microbial Endocrinology research interests are focussed on the relationship between stress and how it influences human and animal infection, particularly the effects of exposure to human stress hormones such as adrenaline and noradrenaline on bacterial growth and virulence. This research has led to the demonstration that stress hormones stimulate biofilm formation in normally harmless skin commensals such as Staphylococcus epidermidis, an important factor in the mechanism by which these inadvertent pathogens form biofilms within indwelling medical devices. This research was funded by the Wellcome Trust and was published as a lead article in the Lancet.
I am also a past Medici Fellow and the past holder of two Innovation Fellowships to develop entrepreneurial activities in the area of life science biotechnology. I am an active inventor, with several patent sets.
Aldriwesh M, Al-Dayan N, Barratt, J and Freestone P (2019). The iron biology of peritoneal dialysis patients may be a risk factor for development of infectious peritonitis. Peritoneal Dialysis International pii: pdi.2018.00052. doi: 10.3747/pdi.2018.00052Koukkidis G, Freestone, P (2018). Salmonella Contamination of Fresh Salad Produce: Prevalence, Impact and Reduction Strategies. J Horti Sci Crop Res 1(1): 102-108
Koukkidis G, Haigh R, Allcock N, Jordan, S and Freestone P (2017). Salad leaf juices enhance Salmonella growth, fresh produce colonisation and virulence. Applied & Environmental Microbiology 83:1. doi: 10.1128/ AEM02416-16. This article was chosen as a special interest feature by the American Society of Microbiology
Sandrini S, Aldriwesh M, Alruways M, and Freestone P (2015). Microbial endocrinology: host–bacteria communication within the gut microbiome. Journal of Endocrinology 225, R1–R15.
Smith CM , Sandrini S, Datta S, Freestone P, Shafeeq S, Radhakrishnan P, Williams, Glenn SM, Kuipers OP, Hirst RA , Easton A J , Andrew PW and O'Callaghan C. 2014. RSV Increases the Virulence of Streptococcus pneumoniae by Binding to PBP1a: a New Paradigm in Respiratory Infection. American Journal of Respiratory and Critical Care Medicine. DOI: 10.1164/rccm.201311-2110OC.
Sandrini, S, Alghofaili, F Yesilkaya, H, Freestone, P, (2014). Host stress hormone norepinephrine stimulates pneumococcal growth, biofilm formation and virulence gene expression. BMC Microbiology 07/2014; 14:180.
Freestone P (2013). Communication between bacteria and their host. Scientifica. Hindawi Publishing Corporation
Haigh R, Kumar B, Sandrini S, and Freestone P (2013). Mutation design and strain background influence the phenotype of Escherichia coli luxS mutants Molecular Microbiology 88:951-969.
Sandrini S, Masania R, Haigh R, and Freestone P (2013). Role of porin proteins in acquisition of transferrin iron by enteropathogens. Microbiology. DOI 10.1099/mic.0.071928-0. This article was chosen as a special interest feature by the Microbiology Society
Freestone, P., Hirst, R.; Sandrini, S., Sharaff, F., Fry, H., Hyman, S., and O'Callaghan, C. (2012). Pseudomonas aeruginosa-Catecholamine Inotrope Interactions: A Contributory Factor in the Development of Ventilator Associated Pneumonia? Chest 142: 1200-1210.
Lyte, M and Freestone, PPE (Editors). Microbial Endocrinology: inter-kingdom signaling in health and disease. Springer Publishers (2010).
I work regularly with the media (journalists, magazines, TV and radio) in the area of food safety and popular microbiology e.g. Which? Magazine. Research funded by the BBSRC on fresh produce infections features as best practice advice on the UK NHS website. Our BBSRC funded salad work has featured on national TV and newspapers
I also write popular science articles: an article on toilet seat hygiene was reported nationally in The Sun and Medicalxpress and was translated into French and Spanish and achieved a >750,000 readership.
I am currently a Microbiology adviser for BBC Radio Leicester. With the station presenters and producers I collaborate on topical science research projects and present articles on microbiology, health and biotechnology subjects.