Data Collection Strategies for Kinetic Crystallography SS

Ulrich Genick

Brandeis University

Movement is indispensable for protein function. Yet currently protein crystallography is dominated by structure determination of proteins in their “resting states”. The emerging techniques of kinetic crystallography overcome this limitation and allow us to catch a glimpse of proteins as they carry out their function. The goal of the talk is to help new users assess the opportunities and difficulties kinetic crystallography presents for their experimental system.

Conceptually kinetic crystallography is simple: A reaction is triggered inside the crystal and either the speed of data collection is increased (true time-resolved crystallography) or the transient intermediate is stabilized (chemical or physical trapping) to make the time of data collection shorter than the lifetime of the intermediate of interest.

The devil – as always – is in the details. Synchronizing reactions inside a crystal presents its own set of unique challenges and both time-resolved and trapping techniques represent unique tradeoffs between various opportunities and challenges. As a result, there is not one single ideal approach to kinetic crystallography. Instead, the most promising combination of activation method and data collection technique depends critically on the nature of the experimental system under study.

Using examples from the literature and our own work, the talk will compare the available activation and data collection methods and contrast their unique strength and weaknesses.