Ryan Karimi
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rkarimi.bsky.social
Ryan Karimi
@rkarimi.bsky.social
14 followers 61 following 0 posts
MD/PhD Student
University of Toronto & SickKids
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Reposted by Ryan Karimi
macleanlab.bsky.social
Happy to share our latest paper. Result of a great collaboration between @sheinerlab.bsky.social @oninopantsu.bsky.social and Alexander Mühleip’s new group.

www.nature.com/articles/s41...
Structure, assembly and inhibition of the Toxoplasma gondii respiratory chain supercomplex - Nature Structural & Molecular Biology
Here the authors demonstrate that the assembly of mitochondrial respiratory supercomplex (III2–IV) from Toxoplasma gondii is critical for parasite fitness. They reveal the basis for cytochrome b inhib...
www.nature.com
May 19, 2025 at 10:22 AM
Reposted by Ryan Karimi
janinebrunner.bsky.social
Cryo-EM structures of mammalian membrane proteins from a single cell culture dish?

Yes, Micro ISOlation (MISO) sample preparation makes it possible.

www.biorxiv.org/content/10.1...

Happy to be part of this exciting story and wonderful collaboration with the Rouslan Efremov lab.
January 16, 2025 at 9:27 AM
Reposted by Ryan Karimi
lowlab.bsky.social
Love this.. 👏

MISO: Microfluidic protein isolation enables single particle cryo-EM structure determination from a single cell colony

www.biorxiv.org/content/10.1...
January 15, 2025 at 4:23 PM
Reposted by Ryan Karimi
johnrubinstein.bsky.social
New preprint!
@zestytoast.bsky.social provides the missing puzzle piece for a structural model of the mycobacterial OxPhos: NDH-2
We show the enzyme forms a dimer resembling eukaryotic, not prokaryotic, NDH-2s, and explain the SAR of a promising class of inhibitors.

www.biorxiv.org/content/10.1...
Overall structure of mycobacterial NDH-2 (class II NADH dehydrogenase) dimer. NDH-2 is the primary entry point for electrons into the mycobacterial electron transport chain. Electrons are transferred from NADH to menaquinone via an FAD cofactor. Comparison of dimers formed by NDH-2 from M. smegmatis, C. thermarum, S. aureus, S. cerevisiae, and P. falciparum. The M. smegmatis dimer looks much more like the eukaryotic dimers (S. cerevisiae and P. falciparum) than the prokaryotic dimers (C. thermarum and S. aureus). Structures for quinolinyl pyrimidine Compounds 13A and 13C, which do not appear to inhibit NDH-2 specifically as shown by enzyme assays, and 2-mercapto-quinazolinone Compound 1, which appears to inhibit NDH-2 specifically. Structure of mycobacterial NDH-2 bound to 2-mercapto-quinazolinone [(2-mercapto-quinazolinone N-cyclohexyl-2-[(4-oxo-1H-quinazolin-2-yl)sulfanyl]acetamide], explaining the protein-inhibitor interaction.
January 9, 2025 at 2:55 PM
Reposted by Ryan Karimi
johnrubinstein.bsky.social
We are hosting a cryo-EM grid nanofabrication workshop on 28 April 2025, as part of the Canadian Cryo-EM Nexus (ccemn.ca).
Learn how to make holey gold or holey carbon grids in your own laboratory!
Space is limited, so please apply at web.cvent.com/event/ee88ac...
January 6, 2025 at 7:28 PM
Reposted by Ryan Karimi
johnrubinstein.bsky.social
Most protein complexes are born only once. V-ATPase assembles over and over as part of its regulatory mechanism, enabled by RAVE (regulator of ATPase of vacuoles and endosomes)
@hanlinw222.bsky.social's 1st struct of RAVE bound to a partial V1 complex now out in PNAS.
www.pnas.org/doi/10.1073/...
Cryo-EM map and atomic model of the RAVE complex (regulator of ATPases of endosomes and vacuoles) bound to a partial V1-ATPase complex Atomic model showing that the RAVE complex binds to a region of the V1 complex subunit A not found in the homologous ATP synthase subunit beta.
December 3, 2024 at 7:34 PM
Reposted by Ryan Karimi
jimhurley.bsky.social
Proud of new work tinyurl.com/yhz4c6ry from the lab by Zhicheng (Chen) Cui using single-particle cryo-EM on liposomes to show how mTORC1 integrates nutrient and growth factor signaling at lysosomes, collab. w/
G. Napolitano,A. Esposito, and A. Ballabio.
November 16, 2024 at 4:31 PM