Greg Chojnowski's Avatar

Greg Chojnowski

@gchojnowski.bsky.social

I build EM and MX models and write software to make it a bit less of a hassle. Some of the code I wrote is a part of CCP4 and CCP-EM. https://gchojnowski.github.io

78 Followers  |  237 Following  |  11 Posts  |  Joined: 13.11.2024  |  1.712

Latest posts by gchojnowski.bsky.social on Bluesky

Ensemble model of the full length Pex5 receptor (different blue color) in complex with Pex8 (green colors).

Key Findings:

Pex8 binds to a novel site on the mostly unfolded N-terminal region of the Pex5 receptor. This interaction is essential for peroxisomal protein import.

Computational modelling reveals the formation of an assembly with the trimeric peroxisomal E3-ubiquitin ligase.

We propose that this action positions the Pex5 receptor for its recycling, a step essential for the entire protein import process.

Why this matters:

Peroxisomes rely entirely on the import of folded proteins to function. Impaired peroxisome function is linked to severe disorders, and recent data show their crucial roles in carcinogenesis and the immune response. Our work elevates Pex8 from an enigma to a central player in this critical biological process.

Read the full story and see the structures here: https://www.biorxiv.org/content/10.1101/2025.08.30.673231v1

#CellBiology #StructuralBiology #Peroxisome #ProteinImport #bioRxiv #Biochemistry

Ensemble model of the full length Pex5 receptor (different blue color) in complex with Pex8 (green colors). Key Findings: Pex8 binds to a novel site on the mostly unfolded N-terminal region of the Pex5 receptor. This interaction is essential for peroxisomal protein import. Computational modelling reveals the formation of an assembly with the trimeric peroxisomal E3-ubiquitin ligase. We propose that this action positions the Pex5 receptor for its recycling, a step essential for the entire protein import process. Why this matters: Peroxisomes rely entirely on the import of folded proteins to function. Impaired peroxisome function is linked to severe disorders, and recent data show their crucial roles in carcinogenesis and the immune response. Our work elevates Pex8 from an enigma to a central player in this critical biological process. Read the full story and see the structures here: https://www.biorxiv.org/content/10.1101/2025.08.30.673231v1 #CellBiology #StructuralBiology #Peroxisome #ProteinImport #bioRxiv #Biochemistry

We are excited to share our latest work, where we unravel the structural and functional secrets of the once-mysterious protein Pex8 revealing how it controls the peroxisomal cargo import receptor Pex5.

Read more here: www.biorxiv.org/content/10.1101/2025.08.30.673231v1

03.09.2025 10:28 β€” πŸ‘ 18    πŸ” 6    πŸ’¬ 1    πŸ“Œ 0
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82 years since the Warsaw Ghetto Uprising The doomed Uprising led to the complete annihilation of Jewish Warsaw.

Today marks the 82nd anniversary of the Warsaw Ghetto Uprising, recognized as the largest act of armed resistance undertaken by Jews during WWII. Launched against insurmountable odds, the rebellion is often cited as one of the defining moments in modern Jewish history.

19.04.2025 07:04 β€” πŸ‘ 53    πŸ” 27    πŸ’¬ 2    πŸ“Œ 1

There may be issues with mappings of some depositions, but the repo doesn't check/solve this. It only parses what's in the PDB already.

27.03.2025 19:26 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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UniProt UniProt is the world's leading high-quality, comprehensive and freely accessible resource of protein sequence and functional information.

It seems to use the same ebi api as www.uniprot.org/id-mapping

27.03.2025 18:48 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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A quote from A People’s History of the United States The problem of democracy in the post-Revolutionary society was not, however, the Constitutional limitations on voting. It lay deeper, beyond the Constitu...

www.goodreads.com/quotes/99381...

a grim reflection on the past and a projection of the future that has just arrived.

15.02.2025 11:06 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Finally!

08.02.2025 11:05 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Cover of the book of "A People's History of the United States" by Howard Zinn

Cover of the book of "A People's History of the United States" by Howard Zinn

High time to understand what's going on in there. Sadly, the historian's perspective is as depressing as that of Faulkner, Steinbeck or Bukowski.

08.02.2025 08:59 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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GitHub - gchojnowski/gapTrick: rebuilds and completes models of protein complexes using AlphaFold2 rebuilds and completes models of protein complexes using AlphaFold2 - gchojnowski/gapTrick

code and a Colab notebok are avilable at
github.com/gchojnowski/...

06.02.2025 10:07 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

- identifies crucial contacts; very useful for selecting mutagenesis targets

- fixes model geometry. In cryo-EM, stereochemistry is usually the best priors you have!

- helps predicting models of weak complexes that AlphaFold3 cannot

06.02.2025 10:07 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
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gapTrick - Structural characterisation of protein-protein interactions using AlphaFold with multimeric templates The structural characterisation of protein-protein interactions is a key step in understanding the functions of living cells. Models of protein complexes provide important insights into interaction me...

I’m happy to share gapTrick, an AlphaFold2-based tool for characterising protein-protein complexes

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

06.02.2025 10:07 β€” πŸ‘ 5    πŸ” 3    πŸ’¬ 1    πŸ“Œ 0
The cover of the book Why We Sleep by Matthew Walker

The cover of the book Why We Sleep by Matthew Walker

The book doesn't really explain why we sleep, but the message is very simple and convincing: "Go the f*k to sleep!". Highly recommended (the book too).

01.02.2025 20:40 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

This might be a good opportunity to remind people that experimental data (diffraction or cryoEM maps) have to be provided with the submission of papers to the IUCr society journals on Structural Biology, Acta Cryst D and F. So referees don’t even have to ask any more!

18.01.2025 12:41 β€” πŸ‘ 19    πŸ” 8    πŸ’¬ 3    πŸ“Œ 0
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We have released version 2 of AlphaPulldown - a general pipeline for high-throughput structural modeling!
Software: github.com/KosinskiLab/...
Preprint: biorxiv.org/content/10.1...

04.12.2024 10:02 β€” πŸ‘ 30    πŸ” 9    πŸ’¬ 1    πŸ“Œ 0
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European Molecular Biology Laboratory With 29 member states, laboratories at six locations across Europe and thousands of scientists and engineers working together, the European Molecular Biology Laboratory is a powerhouse of biological e...

EMBL is Europe’s life sciences laboratory. 🧬πŸ§ͺ

At our sites in Barcelona,​​ Grenoble, Hamburg, Heidelberg, Hinxton, and Rome, we seek to understand life in context, from molecules to ecosystems. πŸ”¬πŸŒ

Follow us for our latest news and updates about research, training, services and more. www.embl.org

21.11.2024 14:06 β€” πŸ‘ 62    πŸ” 21    πŸ’¬ 0    πŸ“Œ 8
https://www.embl.org/about/info/course-and-conference-office/events/stb24-01/#vf-tabs__section-programme

https://www.embl.org/about/info/course-and-conference-office/events/stb24-01/#vf-tabs__section-programme

Really looking forward to welcoming & meeting the participants of our #EMBOStructBio course this morning!

Many of our speakers/tutors are here:
@moalquraishi.bsky.social
@sykhalid.bsky.social
@ezgikaraca.bsky.social
@amjjbonvin.bsky.social
@gchojnowski.bsky.social
@drmelissagraewert.bsky.social

18.11.2024 07:07 β€” πŸ‘ 28    πŸ” 8    πŸ’¬ 0    πŸ“Œ 3
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New GPU-based MMseqs2: 20x faster searches on a single L40S (approx. as fast as a RTX 4090) vs. a 128-core CPU. This work enables to set up a very cost-efficient ColabFold MSA GPU server. 🧡🧡
πŸ“„ www.biorxiv.org/content/10.1...
πŸ’Ύ mmseqs.com
πŸ—žοΈ developer.nvidia.com/blog/boost-a...

15.11.2024 23:02 β€” πŸ‘ 174    πŸ” 59    πŸ’¬ 2    πŸ“Œ 2
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How many of the PDB models that were solved using experimental phasing could have been solved by molecular replacement using models obtained from AlphaFold? #MolecularReplacement #AlphaFold2 #ComputationalMethods t.co/s6EahtcYms

14.11.2024 14:40 β€” πŸ‘ 9    πŸ” 2    πŸ’¬ 1    πŸ“Œ 2
Moorhen Moorhen is a molecular graphics web application based on the Coot desktop program.

there are 2fofc/fofc maps in ccp4 format available in @pdbeurope.bsky.social (EDS map/difference map) and you can open them in coot. but why don't you just fetch them directly in moorhen.org?

13.11.2024 21:18 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Thanks!

13.11.2024 18:52 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

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