Hans Pfalzgraf

Identifying an unusual structural feature in a cytochrome P460 enzyme - ChemShell Structural and computational studies indicate the presence of a haem-lysine double crosslink in Methylococcus capsulatus cytochrome P460.

High resolution structural biology approaches and ChemShell QM/MM simulations reveal an unusual structural feature in a cytochrome P460 enzyme, in research published in @chemicalscience.rsc.org

For more details: chemshell.org/mcp460-doubl...

Adenosine molecule represented as balls and sticks with carbon in red, oxygen in blue and nitrogen in green 🤢

That's one cursed colour scheme for anyone who has learned a little chemistry 😂

Fascinating insights this #FluorescenceFriday, into complement delay-accelerating factor (DAF, CD55), identified by our Ankyron™ AC40301 (red) in HeLa cells (nuclei, blue) on @discoverecho.bsky.social #microscope.
Find out more about our #animal-free Ankyrons™ at www.proimmune.com/ankyron

My protein crystals getting imaged by the Formulatrix Rock Imager. I think it's pretty awesome! 🥰
And convenient to be able to check the images from my desk, including time points to check growth. Beats sitting at a microscope where you can't drink tea! ☕
#Crystallography #ResearchComplexAtHarwell

They resealed the electron storage ring of the synchrotron @diamondlightsource.bsky.social during shutdown to get it ready for more experiments!

The work was challenging, but it seems like the dream job: it's fun, yet could also help save some of the tens of thousands of lives lost every year to this disease.

Smiling Hans in a lab coat sitting with a crystal-harvesting wand in front of a Crystal Shifter robot with a microscope and a foam bucket of liquid nitrogen.

Two beautiful protein crystals shaped like squished pyramids seen in their drop using a light microscope.

This week I harvested about 450 beautiful protein crystals, more than in my 7 previous years of crystallography! These are crystals of a Covid target in which I soaked promising drug fragments to see what binds and how.

A smiling Hans with a staff lanyard, standing inside the experimental hall of Diamond Light Source, the UK national synchrotron. There are the roofs of a couple beamlines and a yellow crane at the back. The curved wall has zone 4 indicated in red.

I started a new job at @diamondlightsource.bsky.social! A 2nd protein crystallography postdoc, this time for antiviral drug discovery 🤩
It's only funded until October this year, but I'm sure I'll find something else after that 😁

Can I be added if I'm a postdoc in protein X-ray crystallography? 😁

Oh yeah I once lost a grid and found it again this way 😂

#Cytochrome #NitrogenCycle #Spectroscopy #Catalysis #Heme #Haem #NitrousOxide #Hydroxylamine #Greenhouse #ProteinResearch #ScientificReview #Biochemistry #MolecularBiology #ProteinStructure #LifeSciences #ResearchInnovation #ScienceCommunity #AcademicPublishing #ProteinFunction

Thanks to all the authors for getting this through, especially Hannah who did most of the work!
@mikehough.bsky.social

A pretty protein structure made mostly of beta-sheets. There are two hemes, one per monomer. In P460, the heme is linked to a lysine residue and can do hydroxylamine oxidation. In one c prime beta, the heme has peroxidase-like activity. In another,it does gas binding.

I'm particularly interested in how these properties in cytochromes P460 are affected by the unusual heme-protein crosslinking. This makes them green, distorts the heme and allows them to oxidise the iron-bound NH2OH to N2O, a greenhouse gas. This is basically what makes them #P460 instead of #P450!

Cytochromes P460 and c′-β: exploiting a novel fold for multiple functions - JBIC Journal of Biological Inorganic Chemistry Two related classes of ligand-binding heme c-containing proteins with a high degree of structural homology have been identified and characterized over recent decades: cytochromes P460 (cyts P460), def...

Our review is out! It's about β-sheet-based cytochromes, which are involved in the nitrogen cycle. We've now summarized their structures, spectra and ligand-binding. 🧪
doi.org/10.1007/s007...

Wow congatulations @cristobaluauy.bsky.social !

For the record, I ended up using BANΔIT as it does the B-factor normalisation for you!
Run it here: bandit.uni-mainz.de
Paper: doi.org/10.1002/minf...

🤣

Thank you so much for adding me!
My supervisor @mikehough.bsky.social came up with the title 😁

Line-angle formula of a heme c with a double crosslink to a lysine residue. The modification compared to a single N-C crosslink are highlighted in red: a double bond is added between the carbons CD and CE of the lysine. The double bond of pyrrole ring D has shifted away from the new C-C crosslink to become exocyclic.

Hello, can I be added? I'm a biochemist currently making cool protein structures.
Fresh pre-print on the discovery a new heme modification: www.biorxiv.org/content/10.1...
Me: orcid.org/0000-0003-05...
More papers to come! And I do good SciComm 😁

Good idea, but actually not the same porphyrin nor the same ion 😋

Thanks James 😁

🤣

I'll give a hint: there's iron in it 😁

Smiley Hans in the lab wearing proper PPE. Using a multichannel pipette to dispense buffers into a crystallisation plate based on electronic lab notes on a tablet.

Hello new followers! 👋
I'm a structural biologist 🧶🧬 currently having fun with unusual kinds of protein crystallography 💎 at Diamond Light Source. 😀
But my 3 years are almost over... 😢
So I'm looking for a lab-based biochemistry job 🧪 in the Oxford area. If you have any leads, please get in touch! 😁

Cooool! That should make it easier to do time-resolved crystallography on it, right? And it will avoid using cow eyeballs 😂
How much protein do you get from a single prep?

A noisy red silhouette of a cat with a half-faded tail. This happens when you take the phases of a tail-less cat and the Fourier magnitudes of a cat with tail.

I do like the phase biased cat! It helps understand why we have to do iterative building and beware of what looks suspiciously like the starting model.
www.ysbl.york.ac.uk/~cowtan/four...

Iris in CCP4i2 is very useful to find amino acid residues that are particularly more mobile at room temperature than in cryogenic conditions! #protein #crystallography 🧪
@glycojones.bsky.social I assume that's not the use you had in mind when leading its development? 😁
🧶🧬

Wow, I didn't know it was possible!

I don't know but I want to 😁
I shall patiently wait for someone to guess..

Thank you very much! 😀