Hello,
I second Sudipta's point. I had a dataset at 3.3 angstrom resolution that was initially indexed as P21 21 21, but did not produce a convincing MR solution. The trick was performing the MR search for all possible spacegroups in the pointgroup. The correct spacegroup was P2 21 21. Good luck, Zach Stern Lab University of Massachusetts Medical School ________________________________ From: CCP4 bulletin board <[email protected]> on behalf of Sudipta Bhattacharyya <[email protected]> Sent: Monday, August 20, 2018 6:15:41 AM To: [email protected] Subject: Re: [ccp4bb] Protein is dimmer in solution, hard to build two chains in crystal structure Hello Zhou, How sure are you about the space group of the solution? Any signs of twinning or t-NCS? Best, Sudipta. On Mon, Aug 20, 2018, 7:36 PM SUBSCRIBE CCP4BB Zhu Qiao <[email protected]<mailto:[email protected]>> wrote: Hi All My protein is dimer both in protein buffer and crystallisation reservoir, which is confirmed by calibration column Supderdex 200 10/300 increase. The crystal can diffract to 3 and the space group was determined to be P212121. The solvent content and Matthews coefficient shows 1 copy, solvent content is 74.5% and Matthews coeff is 4.82 2 cpoies, solvent content is 49% and Matthews coeff is 2.41 . I did MR. I can only get one molecule in ASU and the R work / R free is 0.31/0.35 after several cycles of refinement. There are some uncontinued electron density, which indicating may be one more chain is there. I tried to search the other one by disallow the packing test or increase the packing cut off value in phaser, I can get two molecules, but only one has good fit to the electron density map. The other chain hardly have any electron density. Does anyone have any experience regarding this situation? We appreciate your help. ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.jiscmail.ac.uk_cgi-2Dbin_webadmin-3FSUBED1-3DCCP4BB-26A-3D1&d=DwMFaQ&c=WJBj9sUF1mbpVIAf3biu3CPHX4MeRjY_w4DerPlOmhQ&r=2j-L3MbzL15U9vMrT22s7or1W_AQXlIPHit4v5GiqV8&m=IG--OtkdTChLOkpFd7X3W8CbrxTWdQEE7vXKXv1q-9w&s=HCdsBQIBHxVBXN898lVjPJfoGaD8UGJelK-lbWe9ktg&e=> ________________________________ To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.jiscmail.ac.uk_cgi-2Dbin_webadmin-3FSUBED1-3DCCP4BB-26A-3D1&d=DwMFaQ&c=WJBj9sUF1mbpVIAf3biu3CPHX4MeRjY_w4DerPlOmhQ&r=2j-L3MbzL15U9vMrT22s7or1W_AQXlIPHit4v5GiqV8&m=IG--OtkdTChLOkpFd7X3W8CbrxTWdQEE7vXKXv1q-9w&s=HCdsBQIBHxVBXN898lVjPJfoGaD8UGJelK-lbWe9ktg&e=> ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
