First Instruct Workshop on cryoEM best practices

The First Instruct Workshop on cryoEM best practices took place on 9-10 May at the Research Complex at Harwell and was attended by 29 participants, including from industry (FEI, GSK, Vertex, Astrazeneca). The meeting covered both operational and computational methods through short scene-setting presentations from Instruct Centres (Peijun Zhang, eBIC; Ludo Renault, NeCEN, Bruno Klaholz, IGBMC, Martyn Winn CCP-EM, Jose-Maria Carazo, CNB-CSIC and Juha Huiskonen, OPIC) followed by discussion sessions. A plenary talk by Bridget Carragher (Simons Electron Microscopy Centre, New York) provided a transatlantic perspective and detailed experience in establishing a cryoEM infrastructure, training users and developing new technology. FEI’s strategy for increasing the number of cryo-EM expert users was presented by Matthijn Vos and lessons learnt from their recent pilot course were discussed. The presentations are available for downloading:

Key topics from the discussions included, technical training, sample throughput, pre-screening, data preservation.

A number of common themes emerged from the meeting which are summarized below:-

1. Training

There is a clear and urgent need for technical training on two levels (i) to increase the number of experts to run cryoEM facilities (ii) to increase the skill level of facility users. To address (i) FEI piloted an intensive 9-weeks (January-Match 2017) course at NeCEN organized in a collaboration with CNB and Leiden University. Follow-up shorter courses combined with on-line training are planned.

Currently, practical courses offered for users by cryoEM centres such as eBIC are highly over-subscribed. The online lecture course being developed by FEI will be freely available and could be used as part of training by centres. NeCEN will be introducing a requirement for users to complete online training prior to a data collection visit. At the moment all data are collected by NeCEN staff.

2. Sample preparation

Pre-screening of samples is a pre-requisite for high end microscope use

Throughput of data collection, which averages 1500 images/day is relatively low and appears to be largely limited by microscope set-up time e.g. stage drift settling time, autoloader buffer cycles. Quality assessment of samples is a major factor. The availability of a good 2 Å reference sample would be useful.

3. Data processing and preservation

Scipion is generally accepted as the standard Data processing framework. The issue of how long data is preserved varies between centres.