Crystallographic Analysis with Anomalous Dispersion Effects of Phosphorus Atoms Using Remote and Automated Measurements

Abstract

The recent developments of automated data collection and remote access technologies at synchrotron facility are highly remarkable. Here I describe our recent attempt to identify phosphates using their anomalous signals without visiting synchrotron facility. Crystals were screened using automated data collection with the X-ray at the wavelength of 1.0 Å. Then the solvent around the qualified crystals was removed by deep-UV laser ablation. The diffraction datasets were subsequently collected from the solvent-removed crystals using the X-ray at the wavelength of 2.7 Å. Anomalous Fourier map from the dataset collected with 2.7 Å X-ray was superposed on the electron density map calculated from the dataset collected with 1.0 Å X-ray. The two maps clearly indicated the positions of non-Carbon/Nitrogen/Oxygen atoms in the crystal. Our trial proved that considerable parts of the experiments in the synchrotron facility could be performed from the remote site.