(This question is repeatedly asked.) Replace the "unit cell" parameters in the EM map file, like this:
mapman -b mapsize 8200000 << eof read m1 bigmap.ccp4 ccp4 cell m1 749.8 749.8 749.8 90 90 90 write m1 smallmap.ccp4 ccp4 quit eof (for completeness, mapman originates in http://xray.bmc.uu.se/usf ) Happy Friday, Dan On Fri, 7 Aug 2009, Filip Van Petegem wrote:
Hello all, While trying to perform some docking experiments with crystal structures into cryoEM maps, I found that some deposited EM maps are not at the right size relative to crystal structure coordinates (e.g. a ccp4 formatted deposited EM map looks smaller than a crystal structure that's supposed to represent less than 10% of the map). The problem is independent of the graphics program used (e.g. VMD, chimera, pymol all show the EM map as too small). Is there any straightforward way to get the map to the right scale, using information somehow hidden in the map header? Note that I don't know a priori by how much the EM map would have to be inflated. I'm using the SITUS package for docking - converting from ccp4 to situs, spider or any other common map format all deliver maps with the wrong size. Sincerely, Filip Van Petegem
-- *********************************************** Daniel Anderson, Ph.D. Email: [email protected] Phone: 310-206-3642 Fax: 310-206-3914 Howard Hughes Medical Institute at University of California Los Angeles Lab: Paul Boyer Hall Room 219 For US Postal Service and 2-dimensional, use: Box 951662 MRL5-748 Los Angeles, CA 90095-1662 For UPS, FedEx, DHL, or 2.5-3-dimensional, use: Boyer 219 611 Charles Young Drive East Los Angeles, CA 90095-1570 USA
