Seeing Tiny Things - A Quick Cryo-EM Course

The first part of my PhD involves some quick classes on a variety of research techniques that could potentially be of help to my future project, or ones I'm just plain interested in. Considering my fan girl tendencies over those strings of amino acids it makes logical sense I would be drawn to an alternative method in structural biology and so a Cryo-EM masterclass answered my call. This was a pretty hands-on class considering the training required for a lot of the steps. After being shown each piece of the microscope we were also rewarded with a running dialogue for the price of each part, as interesting as these numbers were, the undertones of '....so please don't break this' and 'that's why you don't get to play with it' were quite apparent. Once over our financial shocks we were able to experience sample preparation and I got to repeat a challenge I had difficulty with since my MRes project: attempting to determine where the surface of liquid Nitrogen was. This was so I didn't expose my sample to the elements after freezing with ethane. As no samples were labelled between the group I'll never know how my attempt faired, but practice is practice.

Image gathering was a series of sequential button presses that were oddly satisfying and we were suddenly on to data analysis. We were given an opportunity to practice using Chimera modelling software to manipulate structures which was great! After weeks of programming and maths I was back to proteins and pumped! A really great masterclass, but maybe I was swayed by the crazy thought of seeing an actual protein image magnified, I would even dare to comment that it was more rewarding then crystallography. I enjoyed freezing samples and 'pressing buttons', seeing that electron burn mark after each image gathered did give me super villain feelings, like some overlord of a death-ray. 

Cryo-EM, short for Cryogenic Electron Microscopy, allows the visualisation of samples that need not have been fixed or stained. This gives further insight into how molecules may function within a cell as they can be captured in their native state and during relevant conformational changes. Previously this method of structure elucidation could not compare to the resolution obtained in methods such as crystallography, however, in recent years, cryo-EM is becoming a tool that can easily compete fairly. The 'resolution revolution' as I heard it mentioned by experts in the field is gaining pace, particularly with the field being awarded a Nobel prize this year.

Ultimately I'm pretty impressed and this was AWESOME so I hope a situation arises within my PhD where I can utilise this tool.