A novel approach for structure analysis of two-dimensional membrane protein crystals using x-ray powder diffraction data

TL;DR

This paper introduces a new method for analyzing 2D membrane protein crystals using x-ray powder diffraction, overcoming previous challenges with overlapping reflections to reliably determine low-resolution structures.

Contribution

The paper presents a novel approach that resolves ambiguities in powder diffraction data, enabling direct extraction of phase information for 2D membrane protein structures.

Findings

Successfully determined bacteriorhodopsin structure at 7 Å resolution

Resolved overlapping reflections in powder diffraction data

Provided reliable phase information from powder data

Abstract

The application of powder diffraction methods in two-dimensional crystallography is regarded as intractable because of the uncertainties associated with overlapping reflections. Here, we report an approach that resolves these ambiguities and provides reliable low-resolution phase information directly from powder diffraction data. We apply our method to the recovery of the structure of the bacteriorhodopsin (bR) molecule to a resolution of 7 angstroms using only powder diffraction data obtained from two-dimensional purple membrane (PM) crystals.