Very excited to have this paper come out in @nchembio! We develop and demonstrate a new methodology for characterizing and engineering enzymes active on mucin-type O-glycoproteins! .

RT @rheabains: Excited to share that our work on sulfated oligosaccharide and glycan synthesis is now live in @J_A_C_S ! Check it out https….

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RT @tomaashby: The Simpsons on PhD students - almost twenty years old & more cutting than ever

RT @EricDLombardi: My latest for @TheHubCanada . CANADA CAN NO LONGER AFFORD ITS ‘SOFT CORRUPTION’ PROBLEM. While I’m wearing a tinfoil hat….

If you or a loved one has been tasked with the discovery or engineering of CAZYmes, then have I got a review for you! In our latest review we cover all that you need to get started, including the fundamentals, recent advances, and even. the dark side.

I'm undoubtedly a bit late to the party but this is an incredible article from the incomparable @MaxGantz_ ! A great way to examine epistatic interactions at ultrahigh-throughputs. Congrats to all involved on such exciting and innovative work! .

🌪️ Check out our whirlwind tour of the latest and greatest advances (well, for when it was published a month ago) in carbohydrate-active enzymes 🌪️. If you look closely you'll also find an unfortunate tale of gambling and co-first authorship order 🤦‍♂️.

I am excited to be selected for this program @AstraZeneca! It's a great privilege to be able to pursue my own idea and especially one that could help patients in the future. The challenge itself was a tremendous experience. Looking forward to the next steps!.

RT @rheabains: Exciting news! Our latest research on characterizing a new GH family is now published in @jbiolchem ! Huge thanks to my amaz….

Of course, this wouldn't have been possible without the incomparable @wakarchuk, @boraston_lab, @lya_sim, and many others + the wonderful environment of @ubcmsl @UBCbiochemistry @UBCChem.

We anticipate that further application of this methodology (which we have coined MELiORA) will open new avenues in protein engineering and enable generation of new enzymatic tools to better understand the myseries of the O-glycoproteome!

One round of directed evolution + DNA shuffling yielded a set of mutants with 5- to 21-fold enhancements in activity. Notably the extents of these enhancements were dependent upon the substrate’s peptide sequence and glycan structure.

In many instances, the substrate specificity of ZmpB might limit scalability as it requires a tri- or tetrasaccharide attached to the peptide substrate. However, because these substrates are made in E. coli (+ every other aspect of the screen) our method is highly scalable.

Finally, as our proof of concept, we carry out the first directed evolution of an O-glycopeptidase. We decided to evolve the O-glycopeptidase ZmpB as it has interesting substrate specificity and is very very slow.

Further, we show that this system is applicable in a FACS-based screen just be co-expressing all components. The loss of FRET is dependent upon having both functional glycosylation and O-glycopeptidase. So, we can screen for both of these activities at ultrahigh-throughputs.

We also show that you can use this system in plate-based screens for glycosidases. Again, we can do this while avoiding many of the difficulties in substrate synthesis as the E. coli do most of the work!

As well, O-glycopeptidases have proven difficult to study because their substrates are inherently complex (requiring both a peptide and glycan portion). Now we can carry out kinetic characterization and probe substrate specificities and other aspects of characterization

We can then use an O-glycopeptidase, a unique class of peptidase which require substrate O-glycosylation for activity, to then read-out the glycosylation state of the probe.

To do so, we made a fluorescent protein FRET pair. We then used engineered E. coli (part of a longstanding collab with @wakarchuk) to glycosylate the linker between the proteins by introducing specific seqs. This glycosylation occurs in vivo with low cost + high yields

We wanted to make glycoprotein substrates for screening to better reflect what we actually want the enzymes to do. And so, we developed a system that allows us to characterize and engineer multiple enzyme activities (glycosidases, glycosyltransferases, and O-glycopeptidases).

Glycoproteins are complex substrates. This fact makes engineering of the enzymes that work on them tricky. In our previous paper ( we showed that the activity of certain enzymes on small molecule screening substrates =/= activity on glycoproteins.