HU-DNA (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption The top two rows show illustrations of crystals and solution structures of bacterial HU proteins with DNA represented by X-ray crystallography and small angle X-ray scattering, respectively. DNA strands are yellow and HU proteins are shades of blue. Soft X-ray tomography was used to visualize bacterial chromatin (in yellow) in wild type and invasive <i>E. coli</i> cells, shown in the bottom row. Credit Michal Hammel/Berkeley Lab Usage Restrictions Editorial use with credit. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.