Pre-session information
Shipping information
Our address for sending dry shippers in advance:
MVLS Urquhart Stores,
University of Glasgow,
464 Bearsden Road,
Glasgow,
G61 1QH
If you are coming to SCMI in person for your session, you are also welcome to bring your specimens on the day.
Travelling to SCMI and Parking
SCMI is located in the Centre for Virus Research (CVR) Sir Michael Stoker Building in the University of Glasgow Garscube Campus
Travelling to SCMI by Public Transport
Travelling to Garscube Campus by car
The main vehicular access to the Garscube Campus is via Switchback Road. If using a navigation app/Sat Nav please use G61 1BD as the postcode; this will take you directly to the Campus Gatehouse where staff will be able to direct you to the Sir Michael Stoker Building. If you plan to travel by car please contact our facility manager James Streetley in advance and he will arrange a parking space for you.
Pixel size and camera set-up
It is worth thinking about how you want the microscope and camera to be configured in advance of your session. You can always discuss this with the staff setting up your session, but having one or two ideas will help speed it up.
Linear or counting
The DE-64 can run in two modes; linear or counting. Counting has a higher DQE but we have to hardware bin the camera by a factor of two. This means that for a given pixel size, a linear image is 4 times larger. So the trade-off is field of view vs. quality. Counting is also slower than linear.
Pixel size (or magification)
Small pixel sizes (high magnifications) are needed to achieve high resolution reconstructions. However, that doesn't mean the smallest pixel size is appropriate for every project. If your complex is sparse or large then the small field of view at high magnifications may not give you very many particles (also a reason to consider linear mode). Equally, if you expect the resolution of your final reconstruction to be limited by some other reason, then it does not make sense to use a very small pixel size. It would be better to collect more particles at a larger pixel size.
Common pixel sizes in linear
Magnification |
Pixel size / Å |
---|---|
40,000x |
1.499 |
50,000x |
1.177 |
60,000x | 0.997 |
Common pixel sizes in counting
Magnification | Pixel size / Å |
---|---|
100,000x |
1.209 |
120,000x |
1.015 |
150,000x |
0.829 |
200,000x |
0.598 |
Training Resources
Video Tutorials and Seminars
Getting Started in Cryo-EM A series of tutorials from Professor Grant Jensen at Caltech
LMB Cryo-EM course MRC Laboratory for Molecular Biology 2017 Cryo-EM course.
Useful Publications
An introduction to sample preparation and imaging by cryo-electron microscopy for structural biology.
Rebecca F. Thompson, Matt Walker, C. Alistair Siebert, Stephen P. Muench, Neil A. Ranson
http://dx.doi.org/10.1016/j.ymeth.2016.02.017
A primer to Single-Particle Cryo-Electron Microscopy.
Yifang Chen, Nikolous Grigorieff, Pawel A. Penczek, Thomas Walz
http://dx.doi.org/10.1016/j.cell.2015.03.050
Session Timings
CRYO ARM 300 data collection sessions run for 48 or 72 hours. The user is only requested to be on site for the first working day of the session. An approximate session is outlined below, although this is dependent upon the requested microscope configuration and the specimen.
UK time | 24h time | |
---|---|---|
9.30am | 09:30 | Arrive at SCMI |
9.30am - 10am | 09:30 - 10:00 | Load samples |
10am - 12pm | 10:00 - 12:00 | Set up imaging conditions, screen grids, take test images |
12pm - 1pm | 12:00 - 13:00 | Gain Reference (if required) |
1pm - 2pm | 13:00 - 14:00 | Collect grid square montages |
2pm - 3pm | 14:00 - 15:00 | Select targets for acquisition |
3pm | 15:00 | Run session, set up data transfer. Adjust settings if necessary |