Julie A. K. McDonald

Very pleased to see this out in @cmijournal.bsky.social - what non-antimicrobial options are there for recurrent #UTI, and what might be the role for #FMT? www.clinicalmicrobiologyandinfection.com/article/S119... @rohmaghani.bsky.social @imperialmdr.bsky.social @imperialbrc.bsky.social #MicroSky

Impacts of antibiotic use, air pollution and climate on managed honeybees in Canada - Nature Sustainability Antibiotic use in managed bee populations prevents losses from infectious diseases but can lead to the emergence of antibiotic resistance. Here the authors study the impact of recent regulatory restri...

New paper from my amazing lab, led by my incredible postdoc, @bdmicro.bsky.social
A Canadian study that is highly relevant to beekeepers everywhere. Check it out! www.nature.com/articles/s41...

Congrats! That's such great news! 😊

Yes, that's a good question! The elderly are potentially exposed to more antibiotics and could also have differences in their diet compared to younger adults, which could impact the availability of nutrients VRE are exposed to in the gut.

Antibiotics fuel the rise of vancomycin-resistant enterococci intestinal colonisation by remodelling the metabolic landscape of the gut microbiome Antibiotics save lives- but also reshape the gut microbiome, unintentionally promoting VRE colonisation. This study reveals how antibiotic-driven metabolic shifts promote VRE expansion and highlights ...

We’ve also written a Behind the Paper blog post to accompany our article, which you can find here: go.nature.com/401ctsa

Vancomycin-resistant enterococci utilise antibiotic-enriched nutrients for intestinal colonisation - Nature Communications Here, the authors show that vancomycin-resistant enterococci grow in the antibiotic-treated gut microbiome by utilising enriched nutrients in the presence of reduced concentrations of inhibitory micro...

In case you missed it, check out our latest paper describing how vancomycin-resistant enterococci exploit antibiotic-mediated killing of gut commensals to grow in nutrient-enriched and metabolite-depleted intestines: doi.org/10.1038/s414... #AMR #GutMicrobiome

Great to see this work from Shiv Radhakrishnan and colleagues out in #GutMicrobes - using network analysis to explore #microbiome #metabolome interactions in an #IBD inception cohort: doi.org/10.1080/1949... @imperialmdr.bsky.social @imperialhepatology.bsky.social #IBDSky #GISky

V nice study this. VRE growth in gut microbiome relies on different short chain fatty acids, which are themselves modulated by antibiotic exposure.

Complex but important to understand how antibiotic resistant bacteria persist in microbiome
@natcomms.nature.com 🧪 #AMR #ClinMicro #IDSky #UTISky

Vancomycin-resistant enterococci utilise antibiotic-enriched nutrients for intestinal colonisation - Nature Communications Here, the authors show that vancomycin-resistant enterococci grow in the antibiotic-treated gut microbiome by utilising enriched nutrients in the presence of reduced concentrations of inhibitory micro...

Vancomycin-resistant 𝙀𝙣𝙩𝙚𝙧𝙤𝙘𝙤𝙘𝙘𝙪𝙨 𝙛𝙖𝙚𝙘𝙞𝙪𝙢 (VRE) thrives in the antibiotic-perturbed gut

VRE gobbles up enriched sugars and amino acids, and loss of short-chain fatty acids (acetate, propionate, butyrate) eliminates natural growth brakes

Therapeutic angle: Prebiotic SCFA mixtures block VRE growth!

A great privilege to work with @julieakmcdonald.bsky.social lab on this new paper, now out in @natureportfolio.nature.com Communications - how #antibiotic-related changes in gut #nutrients and #metabolites promote #VRE colonisation: doi.org/10.1038/s414... @imperialmdr.bsky.social

This microbiome therapeutic could be composed of a mixture of gut commensals that can deplete nutrients (that were enriched with antibiotic treatment) and restore the production of inhibitory microbial metabolites (that were depleted with antibiotic treatment).

This study will help guide the rational design of new microbiome therapeutics that could be used to restrict VRE intestinal growth, and subsequently reduce the development of invasive VRE infections.

Finally, we showed that VRE occupied overlapping but distinct nutrient-defined intestinal niches, where VRE had high growth when cultured with other VRE species and when cultured with other multidrug-resistant pathogens (carbapenem-resistant Enterobacteriaceae).

Killing of gut commensals with antibiotics also resulted in reduced nutrient competition, which led to an increase in the concentration of a wide range of nutrients. We showed that VRE used most of these nutrients as carbon or nitrogen sources to support their growth.

We showed significant but incomplete suppression of VRE growth by individual metabolites that were decreased with antibiotic treatment. However, mixtures of metabolites provided complete or near complete suppression of VRE growth.

Killing of gut commensals with antibiotics resulted in reduced production of many microbial metabolites normally produced by gut commensals.

We showed that VRE colonise the antibiotic-treated intestine due to killing of gut commensals (members of the gut microbiome).

Broad-spectrum antibiotics significantly promote VRE intestinal colonisation, causing the intestine to act as a reservoir for VRE that seed difficult-to-treat infections, such as bloodstream infections.

We showed that intestinal niches occupied by VRE were defined by the abilities of VRE to use specific nutrients that were enriched with antibiotic treatment and their abilities to grow with reduced concentrations of inhibitory microbial metabolites.

Vancomycin-resistant enterococci utilise antibiotic-enriched nutrients for intestinal colonisation - Nature Communications Here, the authors show that vancomycin-resistant enterococci grow in the antibiotic-treated gut microbiome by utilising enriched nutrients in the presence of reduced concentrations of inhibitory micro...

So excited to share a new paper from my lab just published in Nature Communications! We showed that vancomycin-resistant enterococci (VRE) occupied distinct intestinal niches in the antibiotic-treated intestine. doi.org/10.1038/s414... Amazing work by first author Olivia King and colleagues!

Today, Professor Donal Wall, @uofglasgow.bsky.social attended a pitch session as part of the Science, Innovation and Technology Committee's 'Under the Microscope' inquiry to explain why they should be interested in microbiomes.

Newly published study by Prof Lindsay Hall @halllab.bsky.social and Prof Willem van Schaik @wvschaik.bsky.social finding that antibiotic resistant Staphylococcus haemolyticus bacteria are common in premature babies
www.birmingham.ac.uk/news/2025/wi...

We are looking for a new postdoctoral fellow to join our team at NC State University College of Veterinary Medicine, near Research Triangle Park. If you are interested please DM me and or also apply here: jobs.ncsu.edu/postings/219...

🔬🦠 How to make sense of the taxonomic complexity & interpersonal variability of the gut microbiota? We propose that beneath this complexity lies a hierarchy of factors that control gut microbiota assembly. Read more! #Microbiome #GutHealth

authors.elsevier.com/a/1km32_,2Ci...

Klebsiella pneumoniae disrupts vasodilation by targeting eNOS post translational modifications via the type VI secretion system and the capsule polysaccharide Vasodilation is a crucial protective response to inflammation and infection. Endothelial cells control vasodilation through the bioavailability of eNOS-produced nitric oxide (NO), and the generation o...

New pre print! We establish an ex vivo blood vessel model to investigate the effect of infection on vascular physiology in real time. We show Klebsiella inhibits vasodilation in a T6SS-dependent manner by targeting eNOs. Superb work by @safimicro.bsky.social www.biorxiv.org/content/10.1...

9 more days to apply to the #PostDoc position to join our @microclockerc.bsky.social ERC Synergy project if you have background in high throughput cloning and genetic modification of model bacteria
Expertise with liquid handling robots, HTP screening, cloning is preferred!

tinyurl.com/2d2c8fe5

Great to work with the lab of @julieakmcdonald.bsky.social and see this preprint out on @biorxivpreprint.bsky.social, looking at how nutrient availability and microbial #metabolites impact #VRE colonisation in the #antibiotic treated gut: www.biorxiv.org/content/10.1... #MicroSky #GastroSky

Overall, our results demonstrated that VRE occupy distinct intestinal niches in the antibiotic-treated intestine, which was defined by their abilities to utilise specific enriched nutrients and their abilities to grow with reduced concentrations of microbial metabolites.

However, we showed that the niches that VRE and CRE occupy in the intestine are different. We demonstrated that VRE occupied overlapping but distinct nutrient-defined intestinal niches, where VRE had high growth when cultured with each other and when cultured with CRE.

Broad spectrum antibiotics promote the intestinal colonisation by both VRE and carbapenem-resistant Enterobacteriaceae (CRE). We saw a similar enrichment of nutrients and depletion of microbial metabolites with broad spectrum antibiotics that promote both groups of pathogens…