Cryo-protection of protein crystals in intense x-ray beams

Abstract

Large area flat crystal x-ray spectrometer with high integrated intensity for an electron beam ion trap Rev. Sci. Instrum. 71, 4065 (2000)

Macromolecular Cryocrystallography

“…Although radiation damage has been a problem since the early days of protein crystallography, there have been only a few systematic experimental studies (Blake & Philips, 1962;Haas & Rossmann, 1970;Dewan & Triton, 1987;Young, Dewan, Thompson & Nave, 1990;Gonzales, Thompson & Nave, 1992;Young, Dewan & Tilton, 1993;Gonzales & Nave, 1994;Watowich, Skehel & Wiley, 1995) and no comprehensive theory has been presented to date.…”

“…This was realized first by Haas & Rossman (1970). Later, radiation damage was found to be undetectable in a number of experiments performed at cryogenic temperatures, and it was found possible to collect complete data sets from a single crystal (Dewan & Tilton, 1987;Hope, Frolow, yon B6hlen, Makowski, Kratky, Halfon, Danz, Webster, Bartels & Yonath, 1989;Young, Dewan, Thompson & Nave, 1990;Gonzales, Thompson & Nave, 1992;Young, Dewan & Tilton, 1993). In addition to eliminating atomic diffusion, the rigid solvent matrix provides a scaffold against the spreading of damage via 'domino effects' mediated by lattice contacts (Henderson, 1990).…”

“…In some cases, where very high X-ray doses had to be used, it has been necessary to use several crystals to obtain a complete data set even at cryogenic temperatures (Watowich, Skehel & Wiley, 1995;Rodgers, Gamblin, Harris, Ray, Culp, Hellmig, Woolf, Debouck & Harrison, 1995;Yonath, 1996). In fact, the unavoidability of primary radiation damage will always lead to a certain number of destructive events per given dose, imposing a lower limit on the size of crystals from which complete datasets can be collected even with ever stronger synchrotron radiation sources (Henderson, 1990;Gonzales, Thompson & Nave, 1992).…”

Radioprotectant screening for cryocrystallography

“…Radiation damage still occurs in cryocooled proteins and was first described by Gonzalez et al (1992) and further studied by Gonzalez & Nave (1994). Site-specific radiation-induced structural changes within cryocooled protein crystals were reported by several researchers in 2000.…”

Radiation damage in protein crystals at low temperature

“…It would take several days on a monochromatic source to obtain this dose and much longer for a systematic study to be carried out. Therefore, Gonzalez, Thompson & Nave (1992) used the white beam to test this prediction. Using visual estimation of the Laue patterns they observed radiation damage after an absorbed dose of approximately 4 × 1017 keV mm -3.…”