Improved Uniformity of the EMDB Map Archive

September 2010: We are pleased to announce that a more uniform set of maps is now available through our project's search services and ftp mirror sites.

Over this summer, our team carried out a comprehensive remediation project involving every map file archived in the EMDB. Parameters in the CCP4 format map headers were updated to reflect depositor-provided voxel sizes, and map density statistical values (min, max, avg, rmsd) were corrected. In a few cases maps were repositioned to superimpose over fitted PDB models, map handedness was corrected, or protein density was made positive.

Additional details about the remediation effort can be found in our June news item. In addition, a complete description of the operational implementation of CCP4 map format for 3DEM map volumes employed in the remediation effort is available here.