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Julie A. K. McDonald

@julieakmcdonald.bsky.social

170 followers 150 following 25 posts

Associate Professor at the CBRB at Imperial College London. Studying how gut microbiota-mediated colonisation resistance protects the host against infections. https://www.imperial.ac.uk/people/julie.mcdonald

www.imperial.ac.uk

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Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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!

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...

doi.org

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Reposted by Julie A. K. McDonald

Andy Edwards @bugsinblood.bsky.social · 9d

Now published! www.nature.com/articles/s41...

Very nice collaboration with Hoogenboom ( @ucl.ac.uk ) and Bonev ( @uniofnottingham.bsky.social ) labs.

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Reposted by Julie A. K. McDonald

Claudia Contini @continiclau.bsky.social · 19d

I am looking for a motivated #Postdoctoral #Researcher to join my group at Imperial @imperialcollegeldn.bsky.social @imperiallifesci.bsky.social. The project focuses on #Antimicrobial #Materials & #Biomimetic #Interfaces
Please repost!

@imperialsci.bsky.social
www.imperial.ac.uk/jobs/search-...

Description

Please note that job descriptions are not exhaustive, and you may be asked to take on additional duties that align with the key responsibilities ment...

www.imperial.ac.uk

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Reposted by Julie A. K. McDonald

Joe Wanford @jwanford.bsky.social · 23d

🎉 Delighted to share the first pre-print from my lab where we demonstrate that intergenic DNA repeats mediate phase variation of the mucoid phenotype in hypervirulent Klebsiella pneumoniae: www.biorxiv.org/content/10.1... #klebclub

Simple Sequence Repeats Mediate Phase Variation of the Mucoid Phenotype in Hypervirulent Klebsiella pneumoniae

Hypervirulent Klebsiella pneumoniae (HVKp) express a thick mucoid capsular polysaccharide which is essential for virulence and survival in the bloodstream but inhibits epithelial adhesion and invasion...

www.biorxiv.org

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Reposted by Julie A. K. McDonald

Professor Lesley Hoyles @bugsinyourguts.bsky.social · 25d

If you are UK-based and working on any aspect of microbiomes (human, plant, insect, soil, animal, ...), please do sign up to Microbiome-Net for details of networking, funding and training opportunities.

forms.office.com/pages/respon...

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Reposted by Julie A. K. McDonald

Ben Mullish @bhmullish.bsky.social · 27d

Honoured to speak on #FMT #LBPs at the #EHMSG meeting today in session with Nicolas Benech and Jens Walter. Thanks to Gianluca Ianiro for organising, and for even getting a @nobelprize.bsky.social winner for Physics to speak to us, Giorgio Parisi! @imperialmdr.bsky.social #microbiomeclinicians

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Julie A. K. McDonald @julieakmcdonald.bsky.social · Aug 13

Read about our recently published paper on vancomycin-resistant enterococci and the gut microbiome in this news article from @imperiallifesci.bsky.social

www.imperial.ac.uk/news/267313/...

Gut bacteria could help block the rise of antibiotic-resistant superbugs | Imperial News | Imperial College London

New research shows antibiotics upset the gut microbiome, allowing drug-resistant pathogens to spread, but restoring microbial balance could stop them.

www.imperial.ac.uk

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Reposted by Julie A. K. McDonald

Ben Mullish @bhmullish.bsky.social · Jul 29

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

https://clinicalmicrobiologyandinfection.com/article/S1198-…

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Reposted by Julie A. K. McDonald

Emma Allen-Vercoe @emmaallen-vercoe.bsky.social · Jul 29

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...

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...

www.nature.com

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Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 29

Congrats! That's such great news! 😊

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 25

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.

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 22

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

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 ...

go.nature.com

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Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 22

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

Vancomycin-resistant enterococci utilise antibiotic-enriched nutrients for intestinal colonisation - Nature Communications

doi.org

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Reposted by Julie A. K. McDonald

Ben Mullish @bhmullish.bsky.social · Jul 18

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

doi.org

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Reposted by Julie A. K. McDonald

Gabriele Pollara @gpollara.bsky.social · Jul 11

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

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Reposted by Julie A. K. McDonald

ᐯIᑕTOᖇ ᑎIᘔET, ᗰᗪ @nizet.bsky.social · Jul 11

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!

Vancomycin-resistant enterococci utilise antibiotic-enriched nutrients for intestinal colonisation - Nature Communications

www.nature.com

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Reposted by Julie A. K. McDonald

Ben Mullish @bhmullish.bsky.social · Jul 10

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

https://doi.org/10.1038/s41467…

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Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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).

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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.

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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).

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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.

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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.

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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.

Julie A. K. McDonald @julieakmcdonald.bsky.social · Jul 14

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.