open access

https://hdl.handle.net/2115/8533

Comparison of phasing methods for sulfur-SAD using in-house chromium radiation : case studies for standard proteins and 69-kDa protein

英語

chromium X-ray radiation

2005-11

International Union of Crystallography

Acta Crystallographica section D

61(11)

1533-1540

Phasing of the crystal structures of four standard proteins (lysozyme, trypsin, glucose isomerase, and thaumatin) and a novel 69-kDa protein from Thermus thermophilus, TT0570, was performed using the singlewavelength anomalous diffraction of sulfur atoms intrinsically present within the native protein molecules. To utilize the sulfur anomalous diffraction, the data sets were collected using the loop-less data collection method with chromium Kα X-rays of 2.29Å. Three phasing methods, MLPHARE, SHARP, and OASIS-2004, were tested in combination with the DM or SOLOMON density modification method. The results showed that the solvent contents are still an important factor for phasing with the S-SAD method, even when longer wavelength Cr Kα radiation is used. Among the three procedures, the improved direct phasing of OASIS-2004 with its implemented fragment feedback to the direct-method probability calculation gave the best results in determining the initial phases. For all five proteins, almost the entire models could be built automatically.

学術雑誌論文

Accepted Manuscript

Copyright © International Union of Crystallography

09074449