Aug 8, 2016

The hidden treasure in your data: Phasing with unexpected weak anomalous scatterers from routine datasets

BioRxiv : the Preprint Server for Biology
Raghurama P HegdeUdupi A Ramagopal


Single wavelength anomalous dispersion (SAD) utilizing anomalous signal from native sulfurs, or other atoms with Z≤20, generally requires highly redundant data collected with relatively long wavelength X-rays. Here we present experiences with two proteins, where anomalous signal from serendipitously acquired surface bound calcium atoms with data redundancy as low as 10 was utilized to drive de novo structure determination. In both the cases, the calcium atoms were acquired from the crystallization solution, and data collection strategy was not optimized for exploiting the anomalous signal from these scatterers. The X-ray data were collected at 0.98 Å in one case and at 1.74 Å in the other (wavelength optimized for sulfur but anomalous signal from Ca was exploited for structure solution). Similarly, using a test case, we show that the data collected at ~1.0 Å wavelength, where the f″ value for sulfur is 0.28e, is sufficient for structure determination using intrinsic sulfur atoms from a strongly diffracting crystal. Interestingly, it was also observed that SHELXD was capable of generating a substructure solution from high-exposure data with a completeness of 70% for low-resolution reflections extending to 3.5 Å, with relatively ...Continue Reading

  • References
  • Citations


  • We're still populating references for this paper, please check back later.
  • References
  • Citations


  • This paper may not have been cited yet.

Mentioned in this Paper

Calcium [EPC]
Crystal - Body Material
Plain X-ray
Determination Aspects
Calcium ion

About this Paper

Related Feeds

BioRxiv & MedRxiv Preprints

BioRxiv and MedRxiv are the preprint servers for biology and health sciences respectively, operated by Cold Spring Harbor Laboratory. Here are the latest preprint articles (which are not peer-reviewed) from BioRxiv and MedRxiv.

Related Papers

Acta Crystallographica. Section F, Structural Biology Communications
Raghurama P HegdeUdupi A Ramagopal
Acta Crystallographica. Section D, Biological Crystallography
Manuela GorgelThomas Boesen
Acta Crystallographica. Section D, Biological Crystallography
Ganapathy N Sarma, P Andrew Karplus
Acta Crystallographica. Section D, Biological Crystallography
Adeline GouletMiguel Ortiz-Lombardía
Acta Crystallographica. Section D, Biological Crystallography
Qun LiuWayne A Hendrickson
© 2020 Meta ULC. All rights reserved