Friday, May 25, 2018
Chemical mediated proteolysis opens a whole new realm in middle-down proteomics!
Okay -- so -- as much as I love the concept of top-down proteomics, I don't actually do it in our lab. When a new and really difficult protein or proteomics project comes in I try to see if top-down is the solution. I really do. Like every time. With our best-suited equipment to the task (QE HF with protein mode and Fusion gen 1) I've got some size and complexity limitations that always make top-down seem ----just----this----far--- out of reach.
Conversely, I'm seeing more and more projects where trypsin or GluC or any of the other awesome enzymes in our freezer I always forget the keycode to -- just aren't right either.
Is it middle-down time?? It can't be. That only works for monoclonal antibodies, right?
No longer, thanks to this awesome paper from Kristina Srzentic et al.,!
This team details the use of a number of chemicals that can be used for middle down applications all the way down to plotting the sizes of the fragments produced and -- so important, and often overlooked --- provide a table of the mass shifts incurred by such reagents.
Okay -- at the risk of annoying my dear friends at ACS and JPR, I'm putting this table here as my civic duty to people to maybe make it just a little easier to find (ACS, please contact me directly if this is a real problem (email@example.com), p.s., you're the best!)
This is just another great new tool for our utility belts for when the next weird protein (or, more likely, PTM) comes through the door!