A research team has found multiple lineages of archaea that have fully repurposed the TAG stop codon to encode the noncanonical amino acid pyrrolysine. cen.acs.org/biological-c... #chemsky 🧪

Today, I'm grateful that Alanna Schepartz is visiting Tufts. Alanna's leadership of @cgemcci.bsky.social has led to impressive advances in genetic code expansion, including recently published work pushing encoding beyond alpha-amino acids. #ChemSky #ChemChat www.nature.com/articles/s41...

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/...

Well it’s chemistry of course. The reason why organic chemists historically make p-tosylates rather than the simpler benzenesulfonates is that p-tosyl chloride is a cheap byproduct from saccharin synthesis. The ortho isomer is used for saccharin. #chemsky 🧪

>1700 examples???

Finally out in Nature Chem Bio: SNAP-tag2 for faster and brighter protein labeling www.nature.com/articles/s41... Thank you Steffi and Veselin.

How do you turn a carbonyl into sulfur? In this work, Zining from our lab developed a carbonyl-to-sulfur swap enabled by a rationally designed N′-alkyl-hydrazonamide (NAHA) reagent that promotes double C-C bond activation. www.science.org/doi/10.1126/...

Seems a good time to post the “Top types of med chem papers” #ChemSky

Never am I more convinced that I angered an eldritch god in a past life than when I’m trying to pipette a sample in dmso-d6 into a 3mm NMR tube #chemsky

I was having a hard time describing how a plate of cultured cells didn’t look healthy to a new undergrad in the lab. He looked at them and said, “oh yeah, the vibes are off.” Thank god for Gen Z.

Check out our latest preprint describing two structures of ribosomes complexed with the two enantiomers of a β2-hydroxy acid. Our structures show that despite stereochemical differences, both are ultimately well positioned for bond formation within the ribosome! chemrxiv.org/engage/chemr...

Ah we love a classic case of “is this unstable, toxic, and generally annoying reagent *actually* necessary to get this rxn to work or is it just how the first guy did it and no one bothered to change it in the last 30 years??” :))) #chemsky

If you're interested in a break from the doom-and-gloom, may I recommend our article, online today @nature.com A solution to the pyrazole alkylation problem, leveraging S-to-NR atom replacement. Skeletal editing has strategic value, outside of late-stage! www.nature.com/articles/s41...

📰 Great "First Reactions" by @aprillukowski.bsky.social featuring C-GEM's recent thioribose work! pubs.acs.org/doi/10.1021/...

Fluorochemical synthesis directly from PFAS is insane. Beautiful beautiful work from the Gouverneur group #chemsky (Strategies to bypass HF? Now chemistry to enable a circular fluoride economy? When do the conversations about Nobels tend to begin…) www.nature.com/articles/s41...

Stuck waiting for crystals to assign absolute stereochem. Any secret magic conditions for very polar compounds that are somehow also surprisingly greasy?

Woahhhh Talk about a game changer from the Baran lab #chemsky

Share with US students who had their offers of admission withdrawn for PhD programs: Apply to Canada. Check out Canadian professors, and contact us. Our system works differently here, and we are all still, technically, able to accept students for Fall 2025.

After Standing Up for Science most of the day today, my eyes are telling me that it is time to lay down from Science for a bit. #StandUpForScience

Thanks to out @ucberkeleyofficial.bsky.social community for joining us at Stand Up For Science! @jenniferdoudna.bsky.social spoke about how NIH funding supported her PhD & NSF funding supported her development of #CRISPR genome editing. Federal funding is needed for life-saving science!

Awesome turnout for #standupforscience here in Berkeley! Big fan of the research posters turned into rally signs

An email went out yesterday afternoon saying textbooks from the collection of an emeritus professor would be up for grabs starting at 9am today, first come first serve. Tell me why there was a line outside of the door at 8:55am. This dept is ridiculous 😭 #chemsky

Proteins carry out exceptionally diverse molecular functions—even though they are all built on an unvarying polyamide backbone. How much more chemical diversity might be unlocked by editing that backbone? cen.acs.org/synthesis/se... #chemsky🧪

We start our first post on Bluesky with a firework! Very proud of a brilliant team to publish our work on C(sp3)-atom transfer @science.org. www.science.org/doi/10.1126/... It has been a very exciting journey. Thanks @erc.europa.eu

Also in @science.org this week, Max Hansmann’s group return with yet another convenient C-atom transfer agent. This time, a diazo/sulfur ylide hybrid favors spiro-type sp3 products from olefins chemsky 🧪 www.science.org/doi/10.1126/...

Some good news: applications are open for the Weill Institute Emerging Scholars Symposium @ Cornell! Senior PhD students and, now, postdocs interested in networking & presenting their work in cell & molecular biology at Cornell should apply by Apr 14. Please repost! wicmb.cornell.edu/emerging-sch...

Big fan of this work from the Kozlowski lab. My friends and I joke about it a lot but it’s funny how the more synthesis you do, the more you begin to enjoy/appreciate clever analytical strategies #chemsky doi.org/10.1021/acsc...

Hello Bluesky! Excited to join and share my postdoc work with Alanna Schepartz, Matt Francis and @cgemcci.bsky.social now out in JACS: Peptide Backbone Editing via Post-Translational O to C Acyl Shift. Proud of our team of undergrad & early grad students—Check it out! pubs.acs.org/doi/10.1021/...

I am so excited for this opportunity! Also, very grateful to the support from past and current mentors—particularly my PhD advisor Jeff Long and my postdoc mentor Nathan Gianneschi, but also many others along the way.

✨ New from C-GEM in ACS Central Science: Thioesters Support Efficient Protein Biosynthesis by the Ribosome pubs.acs.org/doi/10.1021/... Congrats to Alexandra & Jacob, along with Isaac, Jess, @alexsolivan.bsky.social, @nxhamlish.bsky.social, Katie, Alanna, Jamie, and Scott! #NSFfunded @pubs.acs.org

just got the call. fired. i was the DEI coordinator at the department of chemistry. i was in charge of making all the olefins trans. (am i doing the meme right?) #chemsky

Really excited to see this amazing work out in ChemRxiv from our #ChemCollab between the @uwyoongroup.bsky.social @tehshik.bsky.social and #PfizerChemistry Photochem-mediated oxygen migration into sp3 bonds delivering small ring ethers as well as an OH - methylene transposition #ChemSky 1/

Friends, I'm pleased to draw your attention to two new preprints today describing complementary heteroatom insertion reactions into saturated carbocycles, one from our group and another from the Knowles laboratory. chemrxiv.org/engage/chemr... chemrxiv.org/engage/chemr...

Just explained to 11yo what it means to say amino acids are left-handed by sticking slivers of pizza on two forks and saying “If the crust is facing you, the fork is bent either left or right, but it was just chemists who decided the crust should be facing you and it has no deeper meaning” chemsky

Every time I am forced to download a word doc SI in the year 2025, an angel loses its wings #chemsky

✨ New from C-GEM in Nature Protocols: nature.com/articles/s41... This intact tRNA acylation assay discriminates acyl from non-acyl-tRNA, identifies rare acyl-tRNA species, and can quantify low-yield reactions. Congrats Riley, Isaac, Cameron, Sarah, Alanna! #NSFfunded @natureportfolio.bsky.social

Interviewer: Can you explain this gap on your CV? Chemist: Yeah, that's what's between the HOMO and the LUMO #chemsky

Cool paper from the Renata and Baran labs @science.org from @jakeyeston.bsky.social

A simple new protocol for the removal of alloc carbamate and allyl esters that can be run in open flasks with a moisture stable catalyst--compatible with solid and solution phase peptide synthesis and can be used with traditional small molecules #JOrgChem #ChemSky pubs.acs.org/doi/10.1021/...

WOW!!! Beautiful new Nature paper from Burkart Lab UCSD reveals how non-ribosomal peptide natural product synthetases work together. They use tetrazine click chemistry to capture these huge protein complexes mid-reaction. 3 different snapshots show different states. www.nature.com/articles/s41...

Engineering a ribozyme with aminoacyl-tRNA synthetase activity https://www.biorxiv.org/content/10.1101/2024.12.12.627959v1

Excited to share a major milestone! Our latest work unveils the first example of electron diffraction-guided discovery of natural products. This work represents a breakthrough in leveraging cutting-edge techniques to accelerate natural product discovery. #chemsky Preprint: tinyurl.com/yckd3sbr

True story: “Why would they do it like that? This other way is so much better…” 2 weeks later… “Ohhhhh…(slaps head)”

I love/hate when I’m replicating a paper and spot an easier route than the original one used because now I’m stuck trying to figure out if either A) they didn’t think of it and I’m super smart and clever or B) they did try it and it failed and I’m going to waste a week of my life trying it myself

Our Synthesis Tag (SynTag) for the synthesis of aggregating peptides and proteins is now published in JACS 🥳 Congratulations to first authors Héloïse & Elyse and everyone else involved ✨✨ pubs.acs.org/doi/10.1021/...

So excited to see this published! Thionucleosides can be incredibly challenging to make due to the need for oxidation state changes at sulfur during the synthesis. Collaborating with the Britton group, we’ve been able to make them using a short, selective sequence! pubs.rsc.org/en/content/a...

Very small RNA-reactive reagents can map RNA in crowded spaces in the cell - congrats to Dr. Lu Xiao! doi: 10.1016/j.chembiol.2024.09.009

New paper out of Katya Vinogradova’s lab! www.sciencedirect.com/science/arti...

We are so back Where my other #chemtwitter #chemsky #chembio #chemicalbiology #realtimechem homies at?