Julian Marchesi graduated from Cardiff University with a PhD in biochemistry (1992) and became interested in the role bacteria play in ecosystem function. During his post-doctoral years he developed an interest in the contribution of uncultured microbes to the maintenance and function of ecosystems i.e. molecular microbial ecology. He subsequently secured a Wellcome Trust Fellowship which extended his molecular microbial ecology interest and investigated, with culture independent methods, the diversity and distribution of genes involved in biodegradation of priority pollutants in pristine environments. After a short time investigating the deep biosphere he obtained a Lectureship (2001) in the Department of Microbiology, University College Cork, Ireland where he transferred these “omic” skills into the human gut and started to investigate the human gut ecosystem in health and disease. After 7 years in UCC, he moved back to Cardiff University in 2008 to a senior lectureship, where he investigates the role of the gut microbiome in maintaining host health and initiating diseases not only of the gut, but throughout the host system. In 2015 he was promoted to Professor at Cardiff and in 2016 to Professor at Imperial College London.
His work uses a variety of “omic” approaches such as metagenomics, metatranscriptomics, metabonomics and molecular ecology. Over his 22 year career he has authored over 75 peer-reviewed publications and is an editor/senior editor for ISME Journal, FEMS Microbiology Ecology and BMC genomics and is a current member of the editorial boards of Journal of Medical Microbiology and Microbiome and past member of the Journal Microbiology Methods, Current Issues in Molecular Biology, and Molecular Biology Today.
et al., 2020, Ursodeoxycholic acid enriches intestinal bile salt hydrolase-expressing Bacteroidetes in cholestatic pregnancy, Scientific Reports, ISSN:2045-2322
et al., 2020, Commensal Bacteroidetes protect against Klebsiella pneumoniae colonization and transmission through IL-36 signalling, Nature Microbiology, ISSN:2058-5276
et al., 2020, The association between vaginal bacterial composition and miscarriage: a nested case-control study, Bjog: an International Journal of Obstetrics and Gynaecology, Vol:127, ISSN:1470-0328, Pages:264-274
Walters JR, Marchesi JR, 2019, Chronic diarrhea, bile acids, and Clostridia., Journal of Clinical Investigation, ISSN:0021-9738
et al., 2019, Bile salt metabolism is not the only factor contributing to Clostridioides (Clostridium) difficile disease severity in the murine model of disease., Gut Microbes, Pages:1-16