3) Our surfactant cocktail, SurfACT, is designed with minimal sample-dependent screening in mind and can be used across protein classes and EM sample preparation devices.
2) ) PO, where particles adopt non-random orientations at the AWI, is a leading causes of failure in single-particle cryoEM. We rationally designed a cocktail of four synergistic surfactants that disrupt particle interactions with the AWI to improve reconstruction quality and particle integrity.
1) The Herzik lab is excited to announce our newest preprint in collaboration with the Grotjahn lab! We have developed a surfactant cocktail that seeks to overcome one of the more nefarious problems in #cryoEM, Air-water interface (AWI)-induced damage and preferred orientation (PO).
6) Importantly, we demonstrate that SurfACT can be used with any of your favorite grid prep devices! SPT Labtech chameleon ✅ TFS Vitrobot ✅ Custom manually-operated plunger ✅.
Brian Cook
7) Using cryoET and STA we find that aldolase particles stuck at the AWI not only adopt a single orientation, but these particles are also partially denatured at the AWI! Only when aldolase particles were pushed into bulk ice with SurfACT did they remain intact.
Video
9) This was a fantastic team effort led by Suzanne Enos with a fun and insightful collaboration between the Herzik lab at @ucsandiego.bsky.social and Grotjahn lab at @scripps.edu. #cryoET #cryoEM #HerzikLab @sptlabtech.bsky.social @structurabio.bsky.social @thermofishersci.bsky.social
4) We teamed up with @nanigrotjahn.bsky.social and @hamid13r.bsky.social to do a through examination of SurfACT with four known proteins that suffer from PO. Combining #SPA and #cryoET paired with #STA, we show that SurfACT overcomes PO for these proteins and provides insights into this problem.
8) While we explore SurfACT in our preprint: tinyurl.com/SurfACT-prep..., we show that this cocktail can be a generalizable solution to enable many difficult proteins adopt more ideal behaviors during freezing.
5) We first sought to test SurfACT with a pathologically preferred specimen, hemagglutinin. We find that without SurfACT, the particles adopt a “top-down” view and the density is incomplete. Addition of SurfACT drastically reduces PO, flipping particles and leading to a complete ~2.1 Å density.
Brian Cook
Brian Cook
Brian Cook
The next #CryoEM Current Practices Webinar speaker will be Mark Herzik from UCSD speaking on "Old tools, new tricks: engineering better cryoEM sample preparation workflows through design and chemistry" 6/25/2026 at 12 PM ET / 9AM PT
Register here :
us02web.zoom.us/webinar/regi...
