Tatiana Dimitriu

Fantastic collaboration w/ @dbikard.bsky.social @audeber.bsky.social @rayanchikhi.bsky.social labs led by @jmouradesousa.bsky.social : We assessed the rates of variation of anti-phage systems in P4-like satellites and P2 helper phages. Quick conclusion: Huge variation! We focus on 4 key questions/5

New preprint out on bioRxiv!

www.biorxiv.org/content/10.6...

Can conjugative plasmids be used to control plasmid and pathogen spread?

Follow me down the rabbit hole that led to this story 🧵

A One Health study of Klebsiella pneumoniae species complex plasmids shows a highly diverse and ecologically adaptable plasmidome Plasmids play a pivotal role in the horizontal gene transfer (HGT) of antimicrobial resistance (AMR) and virulence determinants among bacteria. Members of the Klebsiella pneumoniae species complex (Kp...

Fascinating and important study on Klebsiella plasmid diversity

'Plasmids from human, animal and marine [Klebsiella pneumoniae complex] isolates formed shared genetic clusters spanning ecological boundaries'

www.microbiologyresearch.org/content/jour...

🚨 New preprint 🚨

How promiscuous really are conjugative plasmids, and what does that mean for plasmid co-occurrence?

A pleasure to collaborate with @craigmaclean.bsky.social on the first paper of my fellowship!

www.biorxiv.org/content/10.6...

Je ne sais pas comment dire autrement les choses que comme ça : la République va observer une minute de silence en l'honneur du militant d'un mouvement de factieux royalistes, identitaires et antisémites qui ont juré sa perte voilà plus d'un siècle.

Check out our latest preprint from @jnvmartinson.bsky.social and @leosong.bsky.social! 🌟🦠

We found that conjugative plasmids can actively eliminate recipient bacteria that resist plasmid acquisition. 🧵

Co-occurrence is associated with horizontal gene transfer across marine bacteria independent of phylogeny Abstract. Understanding the drivers and consequences of horizontal gene transfer (HGT) is a key goal of microbial evolution research. Although co-occurring

Now out & nicely formatted in @isme-microbes.bsky.social

A big analysis of ocean genomes & metagenomes co-led by former postdocs, now PIs, @gmdouglas.bsky.social & @cyanophage.bsky.social along with co-PIs @lbobay.bsky.social & Samuel Chaffron.

A few highlights... 🧵 (1/n)

doi.org/10.1093/isme...

The paradox of immune systems conservation between prokaryotes and eukaryotes - Nature Reviews Microbiology The widespread prokaryotic immune systems, in particular restriction–modification, CRISPR–Cas and defensive toxin–antitoxin systems, are absent in eukaryotes, whereas relatively rare ones, such as Arg...

Aude Bernheim @audeber.bsky.social and Eugene Koonin discuss one of most interesting questions in the field connecting bacterial and animal immunity!

www.nature.com/articles/s41...

Un poste de Maître de Conférence est ouvert pour rejoindre notre unité à Lyon !

Possibilité de rejoindre mon équipe pour travailler sur:
- caractérisation des mécanismes de défense anti-phage
- transfert horizontal et interactions entre éléments génétiques mobiles

N'hésitez pas à me contacter

Thank you for the invite I had a lovely time! Temperature and light are getting steadily down on my way north.

Hosting of Tatiana’s scientific talk @ CBI touliuse

Today we were thrilled to host @tatianadimitriu.bsky.social at @cbitoulouse.bsky.social @cnrsbiologie.bsky.social
She discussed factors contributing to plasmid spread (defense systems, environmental factors…) - with @benoitjpons.bsky.social

New paper out in @pnas.org, and it made the cover! 👁️

We represent plasmids as circles and mutations as dots, resembling an eye, because in this paper we literally 𝑤𝑎𝑡𝑐ℎ plasmids evolve.

‼️Check Paula’s 🧵 and the paper👇

𝗣𝗹𝗮𝘀𝗺𝗶𝗱 𝗺𝘂𝘁𝗮𝘁𝗶𝗼𝗻 𝗿𝗮𝘁𝗲𝘀 𝘀𝗰𝗮𝗹𝗲 𝘄𝗶𝘁𝗵 𝗰𝗼𝗽𝘆 𝗻𝘂𝗺𝗯𝗲𝗿
www.pnas.org/doi/10.1073/...

I want the world to listen.

What russia is doing now by attacking Ukraine’s energy and heating infrastructure in the middle of winter is an attempt to break us, to make us give up and to erase us as a nation.

But no.
We stand.
It’s cold. It’s dark.
We are not heroes.
We stand.

this is amazing - "listen to wikipedia" as background music

My team at @cbitoulouse.bsky.social is recruiting a postdoc #bioinformatics with solid experience in metagenomic analyses.
Interest in evolution, ecology & MGEs is important.
The offer stands until the perfect candidate is found, and it could be you 🫵

🔁 🙏

#microSky #phagesky #UTIsky
@cnrs.fr

Bacteria chromosomes contain Genomic Islands that provide virulence, antibiotic resistance, MGE-defence,... They transfer between cells, but the mechanism of most remains elusive.

Here we explore the conjugative capacity of these mysterious Genomic Islands.

www.biorxiv.org/content/10.6...

Une opportunité unique de former des étudiants talentueux à la biologie des bactéries à l'ENS Lyon et mener des recherches sur les phages, l'immunité bactérienne, le transfert génétique horizontal (HGT) et/ou les éléments génétiques mobiles au sein du département de bactériologie du CIRI.

Coupling DNA processing to early gene expression drives antibiotic resistance plasmid dissemination The rapid global spread of antibiotic resistance is mediated by conjugative plasmids, yet how these elements establish immediately after entering new bacterial hosts remains poorly understood. Here we...

New bioRxiv preprint from our Lesterlin lab
How early gene expression coupled to DNA processing boosts resistance plasmid spread.
With @nfrk92.bsky.social in collab with Y. Yamaichi lab
👉 doi.org/10.64898/202...

Neisseria gonorrhoeae carries an unusually large number of restriction–modification systems (up to 16!), many of which are phase-variable. How does this affect plasmid transmission in gonococci? doi.org/10.64898/202...

Just treated us to Fazil Say in London playing Bach and himself 😍 and successfully fought off my old student reflex to go for the cheapest tickets as a) I want to see his hands and b) the travel will be by far the most expensive anyway

Within-host evolution of Klebsiella spp. from intestinal carriage to bacteremia Gut colonization by the Gram-negative bacillus Klebsiella pneumoniae is a significant risk factor for extra-intestinal infections. However, the mechanisms by which this opportunistic pathogen causes d...

📣 preprint alert!
We sampled #klebsiella isolates from💩 patients when they entered the hospital & 🩸 after development of infection.

🎯 We tracked phenotypic changes & correlate them w genotypic changes.
@klebclub.bsky.social
-in collab with Clermont-Ferrand lab
#microsky
🧵
doi.org/10.64898/202...

The distinction between virulent & temperate phages gets fuzzier if one can find so many virulent phages in the sequences of bacterial genomes coming from standard lab "pure" cultures. Check Peter's thread on our work and the N&V by Carson & Hynes: doi.org/10.1038/s415...
#phagesky #microsky

🎉 New year, NEW PREPRINT!

Bacteria exhibit astonishing genetic diversity, but where do new genes come from?

My best friend Arya Kaul (/labmate in the @baym lab) investigates how advantageous deletions can spawn new genes - "deletion-born fusions." 🧵:

🔊 Job Opportunity: Postdoctoral Research Fellow in Bacterial Evolution.

Looking to recruit a postdoc to join a UKRI FLF-funded project on antibiotic resistance evolution in the microbiome 🦠

3 years funding, deadline 26th Jan, please share!
hrwebapp.qub.ac.uk/tlive_webrec...

Environment-dependent evolution drives divergent adaptive strategies and parasite dynamics in a minimal community Prophages, phage genomes integrated into bacterial chromosomes, are widespread, yet, the extent to which these resident parasites contribute to host fitness and shape evolutionary trajectories, partic...

Preprint alert📢! 
Ever wondered how much bacterial parasites influence evolutionary outcomes of their host?
➡️ We co-evolved two bacterial strains in conditions in which the costs and benefits of prophage carriage varied

Here is what we found. 
www.biorxiv.org/content/10.6...

#MicroSky #PhageSky
🧵

And Paris-Toulouse by night train with a bed is 37€. That's much lower than the seated version in the UK (where they don't dim the lights at night because if you didn't book a berth you don't want to sleep I guess). With a bed, it'd be something like £150 for Cornwall and £250 for Scotland.

Booking trains, and once again my eurostar tickets will be twice as cheap as the UK part of my journey (Scotland-London, similar from Cornwall). It's not like the Eurostar has to go through a tunnel digged within a Cretaceous layer under the sea or anything.

Bacterial conjugation can restructure biofilms and increase their resilience while constraining host cell dispersal Winans et al. show how plasmid transfer can reorganize bacterial communities into dense aggregates, conferring antibiotic and phage tolerance to otherwise sensitive host cells. Conjugation-dependent a...

Beautiful work from Jay Winans in the Nadell Lab @dartmouthartsci.bsky.social showing IncF plasmid pED208 spreading like wildfire through E. coli biofilms www.cell.com/current-biol...

Environment and physiology shape antiphage system expression Bacteria and archaea encode on average ten antiphage systems. Quorum sensing, cellular, or transcription factors can regulate specific systems (CRISPR-Cas, CBASS). Yet, a systematic assessment of anti...

Bacterial genomes encode a rich repertoire of antiphage systems, but we still know surprisingly little about when these systems are actually expressed.

In this preprint, Lucas Paoli et al, ask what shapes antiphage systems expression in native contexts.
www.biorxiv.org/content/10.6...

Plasmid streamlining drives the extinction of antibiotic resistance plasmids under selection for horizontal transmission Conjugative plasmids play an important role in the spread of antimicrobial resistance (AMR) genes among pathogenic bacteria. This study shows that AMR loss in evolving populations is associated with t...

Our story on plasmid streamlining is now published in PLoS Biology! With @andrewmatthews.bsky.social and @sonjalehtinen.bsky.social
#MicroSky #Mevosky
journals.plos.org/plosbiology/...