The "speed limit" for macromolecular crystal growth
A simple "diffusion‐to‐capture" model is used to estimate the upper limit to the growth rate of macromolecular crystals under conditions when the rate limiting process is the mass transfer of sample from solution to the crystal. Under diffusion‐limited crystal growth conditions, this model predicts that the cross‐sectional area of a crystal will increase linearly with time; this prediction is validated by monitoring the growth rate of lysozyme crystals. A consequence of this analysis is that when crystal growth is diffusion‐limited, micron‐sized crystals can be produced in ~1 s, which would be compatible with the turnover time of many enzymes. Consequently, the ability to record diffraction patterns from sub‐micron sized crystals by X‐ray Free Electron Lasers and micro‐electron diffraction technologies opens the possibility of trapping intermediate enzyme states by crystallization.
© 2018 The Authors. Protein Science published by Wiley Periodicals, Inc. on behalf of The Protein Society. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Received 17 June 2018; Accepted 27 July 2018; First published: 28 July 2018. We thank the Gordon and Betty Moore Foundation and the Beckman Institute at Caltech for their support of the Molecular Observatory at Caltech. We thank Pamela Bjorkman for use of the Leica microscope used in this study. Support from the Howard Hughes Medical Institute Collaborative Innovation Award (Axel Brunger, Stanford, Lead Investigator), NIH Grant GM045162 (DCR) and from NIH Training Grant T32GM7616 to RJA is gratefully acknowledged. The authors declare no conflict of interest.
Published - Arias_et_al-2018-Protein_Science.pdf