Finally, we leveraged all of this to see if O-acetylation was present on human N-glycans from serum. Specifically, we had O-acetylation on NeuGc in mice, and on NeuAc in rats, so the combined approach should uncover if it is present in humans

Short answer: trace amounts in human at best.
#glycotime

We then developed a quality control workflow, using as much information as possible to confirm O-acetylation.
Using MS1, MS2, and LC, we reduced the number of putative identifications by 95%, ensuring the quality of these annotations.

Second level, liquid chromatography:
- O-acetylated structures elute later
- Their peak shape is broader

We're not quite sure why we have broader peak shapes, but it was universal. Further work is ongoing to resolve this, but it could be caused by multiple acetylation positions (more structures!).

Now we're seeing these structures, we want to characterise them for community use, specifically, by LC-MS/MS.

First fragmentation:
- Beam-type (HCD) CID is best, as it generates universally useful fragments for all acetylated structures
- Energy profiles show the expected ratios of these fragments

Traditionally, reduction or permethylation has been optimal to measure glycan structures, but we've previously reported a way to avoid this (link: www.biorxiv.org/content/10.1...).

By performing native glycan analysis, we are suddenly seeing 2x the structures previously observed in rats and mice.

#ausomics was a great opportunity for Protea Glycosciences to share our recent advances in Glycomics and glycoproteomics and see the latest research across four Australian societies including @ozglyco.bsky.social.
It was a productive conference and now we're looking forward to getting back to work.

Proud to announce our business relocation, our local beach.
We’re committed to accelerating glycoscience, so where better to be based than a location where the glycans come to us.
Our LC-MS service engineers are excited for the opportunities provided by this new location.

We're just completing an R&D sprint to identify an LC additive that increases our glycan identifications 3x and enhances glycan charge states by up to 45%🚀.

It's too early to publicly disclose its identity, but here's a results preview.
Interested? Message or email us, we'd love to collaborate.