Malcolm White
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mfwhite2.bsky.social
Malcolm White
@mfwhite2.bsky.social
Molecular microbiologist at the University of St Andrews, Scotland. My scientific interests include: CRISPR, antiviral defence, cyclic nucleotide signalling, archaea, nucleases.
Thinking about your first steps to independent research? We'd love to hear from you. More details below, or contact me directly for details - reposts appreciated!

www.nature.com/naturecareer...
Biomolecular Science Fellowship Day - St Andrews, Fife (GB) job with UNIVERSITY OF ST ANDREWS | 12848597
The School of Biology at the University of St Andrews is inviting applications from outstanding visionary Research Fellow and Future Leader candida...
www.nature.com
November 10, 2025 at 4:44 PM
This is something that is within our power
November 10, 2025 at 3:53 PM
This has to be one of the most subtle signals activating a DS, it blows my mind that there are two different effectors capable of achieving this molecular recognition
Bacteria can sense when a virus starts shredding their genome — by detecting methylated mononucleotides.
Here’s the story of how we discovered the Metis defense system 👇
www.biorxiv.org/content/10.1...
November 6, 2025 at 6:52 AM
Reposted by Malcolm White
Hi everyone, a few years ago, we started a list of labs studying bacterial immunty for students, editors, conference organizers... (currently n=79).

Update time ! Send me a message to 1) add your lab or others 2) Correct info
docs.google.com/spreadsheets...
#Phagesky #Microsky
Labs in bacterial immunity
docs.google.com
November 4, 2025 at 3:06 PM
Very cool.
October 31, 2025 at 11:18 AM
Reposted by Malcolm White
I’m thrilled to share our Retron Eco8 paper published in Molecular Cell today. Thanks all Fu lab members and our collaborators.
👉Phage SSB detection by retron Eco8 msDNA unleashes nuclease-mediated immunity. www.cell.com/molecular-ce...
Phage SSB detection by retron Eco8 msDNA unleashes nuclease-mediated immunity
The cryo-EM structure of the retron Eco8 system reveals an autoinhibited 4:4:4 complex of RT, msDNA, and OLD nuclease. Phage SSB binding to msdDNA unleashes non-specific nuclease activity to restrict ...
www.cell.com
October 30, 2025 at 3:06 PM
Reposted by Malcolm White
Been working on a really strange retron bacterial immune system, here's the preprint: www.biorxiv.org/content/10.1...
Type VI retrons are unlike any other. Phage infection triggers reverse transcription of a DNA fragment that activates translation of a toxin to kill the infected cell.
October 23, 2025 at 7:32 PM
Please tell me what I'm missing here (other than SRM):
October 22, 2025 at 10:51 AM
Reposted by Malcolm White
My home department of Molecular Biology & Biochemistry at UC Irvine is looking to hire a new tenure-track assistant professor in the broad area of structural biology. Come be my colleague! recruit.ap.uci.edu/JPF09887
recruit.ap.uci.edu
October 16, 2025 at 5:07 PM
Reposted by Malcolm White
Perfect timing in the field for a beautiful review on NAD+ in bacterial immunity by @hugovaysset.bsky.social and @audeber.bsky.social @cp-molcell.bsky.social

#MicroSky

www.cell.com/molecular-ce...
October 16, 2025 at 2:58 PM
Rarely was an award more deserved
Congratulations to Philip J. Kranzusch, Ph.D., Professor of Cancer Immunology and Virology, who was one of three scientists awarded top honors at the 2025 Blavatnik National Awards for Young Scientists.

Watch to learn more about his work: bit.ly/4pZUDkF
October 9, 2025 at 5:51 AM
Reposted by Malcolm White
New preprint!

Ever wondered why only a fraction of genomes encode CRISPR immunity? 🧬 🦠

Turns out CRISPR is rarely beneficial against virulent phages, being most beneficial against those for which resistance mutations are rare!

An epic effort by Rosanna Wright

www.biorxiv.org/content/10.1...
Resistance mutation supply modulates the benefit of CRISPR immunity against virulent phages
Only a fraction of bacterial genomes encode CRISPR-Cas systems but the selective causes of this variation are unexplained. How naturally virulent bacteriophages (phages) select for CRISPR immunity has...
www.biorxiv.org
October 6, 2025 at 6:27 AM
My pleasure @erinedoherty.bsky.social and @benmorehouse.bsky.social - for me this was the stand-out discovery of the last year in the field
October 2, 2025 at 7:06 AM
Reposted by Malcolm White
Our story describing the Panoptes bacterial immune defense system is now finally peer-reviewed and published today! www.nature.com/articles/s41...
The Panoptes system uses decoy cyclic nucleotides to defend against phage - Nature
The Panoptes antiphage system defends bacteria by detecting phage-encoded counter-defences that sequester cyclic nucleotide signals, triggering membrane disruption and highlighting a broader strategy of sensing immune evasion through second-messenger surveillance.
www.nature.com
October 1, 2025 at 4:05 PM
Reposted by Malcolm White
Today in @nature.com , we highlight how a cousin of CRISPR-Cas10, mCpol, establishes an evolutionary trap in anti-phage immune systems.

Check out @erinedoherty.bsky.social and my work from @doudna-lab.bsky.social lab here:
www.nature.com/articles/s41...
A miniature CRISPR–Cas10 enzyme confers immunity by inhibitory signalling - Nature
Panoptes, an anti-phage defence system against virus-mediated immune suppression, is revealed.
www.nature.com
October 1, 2025 at 5:57 PM
Reposted by Malcolm White
You’ve heard of ubiquitination, meet deazaguanylation: Doug Wassarman in our lab discovered phage defense pathways have co-opted Q nucleobase biosynthetic enzymes to catalyze a new form of protein conjugation chemistry @science.org

www.science.org/doi/10.1126/...
September 25, 2025 at 7:16 PM
Reposted by Malcolm White
Do notions like “programmed #cell death” (PCD) and the endogenous–exogenous death distinction apply to microbes? In our new chapter, we argue that an evolutionary concept of PCD extends across the tree of life, including microbial taxa 👇📃 link.springer.com/chapter/10.1... #evosky #HPbio #philsci 🦠 🔬
September 22, 2025 at 3:06 PM
Reposted by Malcolm White
Looking for a new approach to studying or eliminating phages? Check out our study introducing anti-phage ASOs (antisense oligos) out in @Nature today. nature.com/articles/s4158…
September 10, 2025 at 3:40 PM
Reposted by Malcolm White
AI could be used for REF, says Royal Society president.

The president of the Royal Society has suggested that artificial intelligence could ease the burden placed on academics by the Research Excellence Framework and peer review.

www.researchprofessionalnews.com/rr-news-uk-c...
AI could be used for REF, says Royal Society president - Research Professional News
Research Excellence Framework is “not best use of human brainpower”, Adrian Smith tells Lords committee
www.researchprofessionalnews.com
September 10, 2025 at 9:29 AM
The beginning of the end for PIs?
September 10, 2025 at 7:13 AM
Some good stuff in here 😊
A new theme issue of #PhilTransB examines the evolutionary history of bacterial immune systems, their modes of action, and the patterns how different bacterial immune systems are distributed across different ecosystems. Read: buff.ly/Z4qdxY1
September 6, 2025 at 8:13 PM
This area is developing at breakneck speed - big advance here
Preprint: De-novo design of proteins that inhibit bacterial defenses

Our approach allows silencing defense systems of choice. We show how this approach enables programming of “untransformable” bacteria, and how it can enhance phage therapy applications

Congrats Jeremy Garb!
tinyurl.com/Syttt
🧵
Synthetically designed anti-defense proteins overcome barriers to bacterial transformation and phage infection
Bacterial defense systems present considerable barriers to both phage infection and plasmid transformation. These systems target mobile genetic elements, limiting the efficacy of bacteriophage-based t...
www.biorxiv.org
September 2, 2025 at 12:08 PM
Reposted by Malcolm White
New story out today. I traced three anonymous Facebook pages back to the Epoch Times, which is banned by Meta. The pages were branded as 'educational research centres' and advertised surveys to collect political opinions and contact data from Canadians. They were seen over 22 million times.
Meta banned the Epoch Times from advertising. Then it accepted $300k in new ads targeting Canadians
In the past 12 months, The Epoch Times has spent over $300,000 on Facebook and Instagram ads promoting political surveys to collect the emails of Canadians using a series of anonymous pages.
www.nationalobserver.com
August 21, 2025 at 12:25 PM
Reposted by Malcolm White
Ever wondered why some bacteria have multiple CRISPR-Cas systems? Our new study led by Leah Smith shows how type I CRISPR systems can promote the acquisition and retention of new spacers into a co-occuring type III system. www.sciencedirect.com/science/arti...
Type I CRISPR-Cas immunity primes type III spacer acquisition
CRISPR-Cas systems are diverse, with microbes harboring multiple classes and subtypes. Type I DNA-targeting and type III RNA-targeting systems often c…
www.sciencedirect.com
August 18, 2025 at 3:06 PM