Dear all: I am currently refining a structure solved by MAD and somehow the R factor got stuck around 30% with 2.2 resolution.
There are four molecules in one ASU. Two had very good density map and the other two were not equally good. I tried using NCS during refinement but it did not help much. Then I checked my data. Actually I found that there are alternate layers of strong and weak reflections. THe crystal is in a thin-plate shape with orthorombic space group. Then I looked at my molecular replacement solution from Phaser using my native data. Actually phaser gave two sets of solutions, which showed slightly different positions. You can also see that there is a translation inside the same set of solution. SOLU SET RFZ=12.8 TFZ=21.4 PAK=0 LLG=452 RFZ=10.7 TFZ=47.9 PAK=0 LLG=1693 RFZ=13.0 TFZ=47.6 PAK=0 LLG=2791 RFZ=10.7 TFZ=46.1 PAK=0 LLG=4045 SOLU 6DIM ENSE ensemble1 EULER 184.052 0.185 175.770 FRAC -0.49889 -0.00218 -0.00000 SOLU 6DIM ENSE ensemble1 EULER 225.116 0.167 134.696 FRAC -0.47056 0.49706 0.00051 SOLU 6DIM ENSE ensemble1 EULER 359.333 31.677 180.633 FRAC 0.75769 -0.71475 -0.14004 SOLU 6DIM ENSE ensemble1 EULER 359.373 31.969 180.711 FRAC 0.73074 -0.21423 -0.14108 SOLU SET RFZ=12.8 TFZ=21.4 PAK=0 LLG=452 RFZ=10.7 TFZ=47.9 PAK=0 LLG=1693 RFZ=13.0 TFZ=47.6 PAK=0 LLG=2791 RFZ=10.7 TFZ=47.3 PAK=0 LLG=4042 SOLU 6DIM ENSE ensemble1 EULER 213.115 0.173 146.741 FRAC -0.49931 -0.00269 0.00045 SOLU 6DIM ENSE ensemble1 EULER 248.173 0.254 111.665 FRAC -0.47091 0.49661 0.00101 SOLU 6DIM ENSE ensemble1 EULER 359.399 31.602 180.578 FRAC 0.75808 -0.71455 -0.13980 SOLU 6DIM ENSE ensemble1 EULER 359.378 31.255 180.361 FRAC 0.78370 -0.21555 -0.13830 I remember there is a discussion in CCP4bb about the same topic with the focus of pseudo-symmetry or translational pseudo-symmetry. Can anybody give some troubleshooting about my issue? Thanks a lot and have a nice weekend, Jerry McCully _________________________________________________________________ Windows Live: Keep your friends up to date with what you do online. http://windowslive.com/Campaign/SocialNetworking?ocid=PID23285::T:WLMTAGL:ON:WL:en-US:SI_SB_online:082009