Josh Ramsay

I think your results clearly show that transduction isn't a preferred mechanism of transfer for staphylococcal plasmids! :p

Cracking the code of life's molecular machinery Groundbreaking research pioneered by UWA is shedding light on the intricate dance between proteins, DNA and RNA – the fundamental building blocks of life,

www.uwa.edu.au/news/article...

Microbial Culture Club, Schott Duran Duran, Fleetwood MacConkey

Microbial Culture Club, Schott Duran Duran, Fleetwood MacConkey

We certainly haven’t finished with RdfS yet. Our molecular genetics data clearly suggest RdfS has a more direct role in the activation of ICE conjugation genes, we just don’t know exactly how yet. Hopefully it won't take another 20 years to find out!

Callum identified several large 30-40bp DNA regions specifically bound by RdfS but with very little sequence conservation. He also showed the unique N-terminal helix was critical for ICE excision and conjugation.

wHTH domains are common and the RdfS structure could been boring. Thankfully it wasn't. RdfS in the absence of DNA forms infinite helical polymers joined together by a unique N-terminal helix that absent in other wHTH excisionases.

Excision and transfer of the Mesorhizobium loti R7A symbiosis island requires an integrase IntS, a novel recombination directionality factor RdfS, and a putative relaxase RlxS The Mesorhizobium loti strain R7A symbiosis island is an Integrative Conjugative Element (ICE), herein termed ICEMlSymR7A, which integrates into a phetRNA gene. Integration reconstructs the phetRNA g...

Inspired by undergrad bioinformatics lectures (P. Stockwell & C. Brown), I used PSI-BLASTP to iteratively search for excisionase sequences in rhizobia, and identified rdfS as the first gene in an operon containing transfer genes and a conjugative relaxase RlxS. doi.org/10.1111/j.13...

I was fascinated by phage integrases and was sure the tyrosine recombinase IntS, of the symbiosis ICE, must have an excisionase to stimulate excision. But unlike most integrases, intS didn’t have an excisionase gene nearby.

Structural basis for control of integrative and conjugative element excision and transfer by the oligomeric winged helix–turn–helix protein RdfS Abstract. Winged helix–turn–helix (wHTH) proteins are diverse DNA-binding proteins that often oligomerize on DNA and participate in DNA recombination and t

Congrats @callumverdonk.bsky.social on your 1st-Author NAR paper doi.org/10.1093/nar/... together with @charliebondxray.bsky.social, characterising RdfS, the multifunctional recombination directionality factor ‘excisionase’ of the symbiosis islands (Integrative & Conjugative Elements).

We propose that RdfS oligomers recognise larger DNA sites, perhaps as preformed oligomers and through an indirect readout mechanism that facilitates binding specificity over large regions with low sequence conservation.

Much molecular genetics and 20 years later, Callum and Charlie Bond use some very clever solutions to solve the RdfS structure from an unusual crystal doi.org/10.1107/S205... demonstrating that like other excisionases, RdfS is a unique winged-helix-turn-helix protein.

This is a special paper for me, as rdfS was the first gene I ever made a functional prediction for 20 years ago as a 1st-year PhD student. The symbiosis island had recently been discovered (Ronson laboratory) and the 500kb sequence had just been completed (Sanger sequencing!).

Thanks!

Is it possible to share a copy of this? I don't have access but would love to read!

The International Society for Plasmid Biology and other Mobile Genetic Elements are finally in Bluesky!! 😎😎😎

Unexpected Richness of the Bacterial Small RNA World I stumbled onto a small RNA (sRNA) induced by oxidative stress when I did the “wrong” northern blot experiment as a second-year graduate student. I wa…

Susan Gottesman and Gisela Storz, pioneers in regulatory RNA research, reflect on their personal scientific journeys and the evolution of their groundbreaking group research in two compelling articles.

Gigi:
www.sciencedirect.com/science/arti...

Susan:
www.sciencedirect.com/science/arti...

#RNA

Arming the enemy: the evolution of resistance to self-proteins A remarkable range of novel antibiotics is attracting increasing interest as a major new weapon in the campaign against bacterial infection. They are based on the toxic peptides that provide the innat...

Given hyperbole about this paper www.nature.com/articles/s41... in the news today (eg www.bbc.co.uk/news/article...) it is a good day to post this classic from >20 years ago: www.microbiologyresearch.org/content/jour...

I can't believe it's almost time for our MGE meeting. I'm so excited to spend time chatting about mobile elements with such a great line up of speakers and topics. www.mgeaus.org/full-program

Aussie MGE scientists, remember to get your MGEAUS abstracts in this week for our first MGE meeting in Melbourne this Feb!

I personally don't agree. I think more thorough review is more important, even when it doesn't go your way. Also, the pressure to publish so frequently somewhat diminishes the value of individual publications and supports the publish or perish situation. I prefer to spend more time on publications.

Register and/or submit abstracts for the national Australian meeting on MGE at mgeaus.org

Could you add me please and @mgeaus.bsky.social ?

What could be a better way to start your week than by registering, and submitting your abstract for MGE AUS?

Register at MGEAUS.ORG today!

Two weeks to go to get your abstracts in for MGE AUS!

- A meeting dedicated to mobile genetic elements research in Australia

- ECR and Student focused

- Travel sponsorships available for many state branches

- Amazing keynote speakers, with a two day program coming soon

Register at mgeaus.org