Center Update June 28th, 2019

By | Center Update
1) Krios
Krios has been functioning well since the HT and FEG Tip replacement. We had over 6 user collect single particle data. Speeds were ~320/hour for a 3×3 hole pattern with 3 images per hole, and ~70/hour or ~160/hour  for stage movement between each hole with either 1 or 3 exposures per hole respectively. There are still steps to improve and optimize in our collection routine (better centering, faster atlases ) which we will continue to work on in the upcoming weeks. As a reminder, the schedule will remain as follows until Arctica is fully functional:

Monday – Songye and myself will help to set up screenings for 2 to 3 users. This will involve collecting an Atlas on all of the loaded grids and 1 high mag image to see particle distribution or fiducial marker density.

Tuesday – Songye and myself will help to set up data collection for 2 users. Maximum of  3 previously screened grids per user, loaded at the beginning of the day.
Wednesday – Friday – will be used by us to further test the new equipment, improve on collection strategies, for any maintenance that might need to occur, and as a buffer in case of down time. We will try to keep the period for which these days are reserved for our use as short as possible. After we are happy with our use of the K3, we will use these days to start training users new to SerailEM to be independent. (Although most of these days were used for user collections since the Krios repairs)
Saturday through Monday 8 am – are open for users independent with SerialEM operation.

For all reservations, please contact Songye and myself first . Remember to include the Idea Elan Project and PTA to use for reservations.

2) Arctica
Arctica is down for the K3 upgrade. The installation of the K3 has been delayed slightly until July 8th as the result of an unusual configuration of our microscope. The Falcon came equipped with a focal extender, which effectively increases the distance between the camera and the sample, which results in a smaller pixel size. The K3 can not be fit on the microscope with the extender present. Through out this week Robert had to remove the Falcon, Ceta, extender, and then remount the Ceta. After every step the microscope had to be pumped down and checked for any leaks. Everything went well and Arctica is now ready for the K3 install.
Until July 8th, Arctica can be used to collect micro-ED data. If you are interested in signing up for collection, please let me know.
3) Caltech EM Slack group
Last year I have created a Slack group for Caltech users to use as a virtual gathering place to discuss any topics regarding (cryo) electron microscopy. If you are not a member yet, please contact Andrey for an invite.
I am always open to suggestions and recommendations on how to improve it and make it more useful.
4) Acknowledgement / Citation Reminder
Please remember to include “(Cryo) Electron microscopy was performed in the Beckman Institute Resource Center for Transmission Electron Microscopy at Caltech. “ (or a variation of, required to contain BI and the Center’s name) in the Acknowledgements section of your papers that used any of the Center’s resources. Further, please remember to forward us the citations to these papers. They are very helpful in assessing the productivity of the Center, as well as a reporting tool for funding agencies.
Stay tuned for further developments! And, as always, let us know if you have any questions, concerns, or suggestions.

Alasdair Receives Queen’s Honors

By | Featured

Alasdair McDowall, the first manager of the BI Cryo-Electron Microscopy Resource Center and currently the lab manager for Grant Jensen, has been appointed as a Member of the Order of Australia by Her Majesty HRH Queen Elizabeth II in the 2019 Queens Birthday Honors list. Appointment to the Order of Australia confers the nation’s highest recognition for outstanding achievement and service among its citizens.

The citation recognizes Alasdair’s “significant service to science, particularly in the field of electron microscopy.”

Nobel Contributions

By | Featured

The 2017 Nobel Prize in Chemistry was awarded jointly to Jacques Dubochet, Joachim Frank, and Richard Henderson “for developing cryo-electron microscopy for the high-resolution structure determination of biomolecules in solution.” One of our own, Alasdair McDowall, was at the front lines working together with Jacques to develop vitrification as a way to preserve samples in their native state for EM. Caltech Magazine featured an interview with Alasdair in the Spring 2018 edition. Read more here.

Publications from Jacques and Alasdair leading to the Nobel Prize:

  1. Dubochet, J., and McDowall, A. W. (1981) Vitrification of pure water for electron microscopy. J. Microsc. 124, 3-4
  2. Dubochet, J., Chang, J. J., Freeman, R., Lepault, J., and McDowall, A. W. (1982) Frozen aqueous suspensions. Ultramicroscopy 10, 55-61
  3. Dubochet, J., Lepault, J., Freeman, R., Berriman, J. A., and Homo, J. C. (1982) Electron microscopy of frozen water and aqueous solutions. J. Microsc. 128, 219-237
  4. Lepault, J., Booy, F. P., and Dubochet, J. (1983) Electron microscopy of frozen biological suspensions. J. Microsc. 129, 89-102
  5. Adrian, M., Dubochet, J., Lepault, J., and McDowall, A. W. (1984) Cryo-electron microscopy of viruses. Nature 308, 32-36
  6. Dubochet, J., Adrian, M., Lepault, J., and McDowall, A. W. (1985) Emerging techniques: Cryo-electron microscopy of vitrified biological specimens. Trends Biochem. Sci. 10, 143-146
  7. Dubochet, J., Adrian, M., Chang, J.-J., Homo, J.-C., Lepault, J., McDowall, A. W., and Schultz, P. (1988) Cryo-electron microscopy of vitrified specimens. Q. Rev. Biophys. 21, 129-228