The Pseudomonas aeruginosa sirB2 gene is a fitness determinant of anaerobic growth and its inactivation affects virulence and rugose small colony variants emergence Pseudomonas aeruginosa is the leading cause of death in cystic fibrosis (CF) patients, yet the genetic mechanisms driving its fitness in the host remain poorly defined. Previously collected transcr...

Can losing a gene make #Pseudomonas aeruginosa more dangerous?
In our new study, loss of sirB2, a fitness factor expressed in #cysticfibrosis lungs under oxygen limitation, drives redox imbalance, RSCV emergence, #biofilm formation and hypervirulence.
🔗 www.tandfonline.com/doi/abs/10.1...

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The antimycotic 5-fluorocytosine is a virulence inhibitor of uropathogenic Escherichia coli and eradicates biofilm-embedded bacteria synergizing with β-lactams | Antimicrobial Agents and Chemotherapy Urinary tract infections (UTIs) are a widespread public health concern both in community and hospital settings (1). Escherichia coli is the leading pathogen behind UTIs worldwide (2). Notably, uropath...

🚨 New paper alert! 🚨 Our latest study on the antivirulence & biofilm-killing effects of 5-fluorocytosine against UPEC is now published in Antimicrobial Agents and Chemotherapy (@asm.org)!

🔬 Read it here: journals.asm.org/doi/10.1128/...

#MicroSky 🦠 #UTISky #UTI #Antimicrobials

Leveraging Engineered Pseudomonas putida Minicells for Bioconversion of Organic Acids into Short-Chain Methyl Ketones Methyl ketones, key building blocks widely used in diverse industrial applications, largely depend on oil-derived chemical methods for their production. Here, we investigated biobased production alternatives for short-chain ketones, adapting the solvent-tolerant soil bacterium Pseudomonas putida as a host for ketone biosynthesis either by whole-cell biocatalysis or using engineered minicells, chromosome-free bacterial vesicles. Organic acids (acetate, propanoate, and butanoate) were selected as the main carbon substrate to drive the biosynthesis of acetone, butanone, and 2-pentanone. Pathway optimization identified efficient enzyme variants from Clostridium acetobutylicum and Escherichia coli, tested with both constitutive and inducible expression of the cognate genes. By implementing these optimized pathways in P. putida minicells, which can be prepared through a simple three-step purification protocol, the feedstock was converted into the target short-chain methyl ketones. These results highlight the value of combining morphology and pathway engineering of noncanonical bacterial hosts to establish alternative bioprocesses for toxic chemicals that are difficult to produce by conventional approaches.

Leveraging engineered #Pseudomonas putida minicells for bioconversion of organic acids into short-chain methyl ketones by @katekozaeva.bsky.social, Manu Nieto, Max Stammnitz et al. ACS #SynBio #OpenAccess
pubs.acs.org/doi/10.1021/...

On Fri Dec 13 15:00-17:00 CET join @krastevalab.bsky.social, George O'Toole, and me for the @asm.org Sweden Finland Lecture series 2024 mini-symposium on #biofilm and #c-di-GMP signaling!

#microsky🦠🧫
Zoom ki-se.zoom.us/j/6761509723...

The antimycotic 5-fluorocytosine is a virulence inhibitor of uropathogenic Escherichia coli and eradicates biofilm-embedded bacteria synergizing with β-lactams Objectives: Biofilm increases bacterial antibiotic tolerance, posing a challenge for treating biofilm-associated infections in clinical settings. 5-fluorocytosine (5-FC), an FDA-approved antifungal an...

Breaking through #biofilm! Our preprint shows that combining flucytosine with β-lactams kills #UPEC hidden inside biofilms! Plus, flucytosine inhibits virulence, prevents #biofilm formation, and reduces pathogenicity, all at sub-MIC levels
#MicroSky 🦠🧫 #UTISky #UTI
www.biorxiv.org/content/10.1...

The antimycotic 5-fluorocytosine is a virulence inhibitor of uropathogenic Escherichia coli and eradicates biofilm-embedded bacteria synergizing with β-lactams https://www.biorxiv.org/content/10.1101/2024.11.20.624304v1 Objectives: Biofilm increases bacterial antibiotic tolerance, posing a challenge for treating biofil

The antimycotic 5-fluorocytosine is a virulence inhibitor of uropathogenic Escherichia coli and eradicates biofilm-embedded bacteria synergizing with β-lactams www.biorxiv.org/content/10.1101/2024.11....

Biofilm Starter Pack on the Blue place

go.bsky.app/HF1jeCQ

Excited to see many in the bacterial pathogenesis community joining here in the last few weeks, so here's a Starter Pack to help make connections. Reply/DM to be added to this or future Packs. #Microsky go.bsky.app/VH64BaY

Widespread alterations in systemic immune profile are linked to lung function heterogeneity and airway microbes in cystic fibrosis Excessive inflammation and recurrent airway infections characterize people with cystic fibrosis (pwCF), a disease with highly heterogeneous clinical o…

Our new work "Widespread alterations in systemic immune profile are linked to lung function heterogeneity and airway microbes in cystic fibrosis" is out: flow cytometry, metatranscriptomics, CF immune profile, lungs microbes, ppFEV1 heterogeneity and much more!
www.sciencedirect.com/science/arti...

Several years after starting the project, the first paper is out! It is also my first time playing with clinical immunology more than microbiology!

Congratulations to all the authors!

openres.ersjournals.com/content/earl...

Fluoropyrimidines affect de novo pyrimidine synthesis impairing biofilm formation in Escherichia coli Antivirulence agents are considered a promising strategy to treat bacterial infections. Fluoropyrimidines possess antivirulence and antibiofilm activi…

New from the lab! Fluoropyrimidines as antibiofilm compounds in Escherichia coli and their potential mechanisms of action. Out in "Biofilm" journal! Congratulations to our PhD student Srikanth Ravishankar!
#MicroSky
www.sciencedirect.com/science/arti...

Cystic fibrosis systemic immune profile is associated with lung microbes and characterized by widespread alterations in the innate and adaptive immune compartments www.biorxiv.org/content/10.1101/2023.08....