?Hello Zhu,
The implication being that one can have half of a dimer in the asymmetric unit without any issues (biological or crystallographic). And having a R/Rfree after a bit of refinement of the values you report for a 3 A data set is not that far off from being appropriate. Best of luck, tom Tom Peat Proteins Group Biomedical Program, CSIRO 343 Royal Parade Parkville, VIC, 3052 +613 9662 7304 +614 57 539 419 tom.p...@csiro.au ________________________________ From: CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK> on behalf of Eleanor Dodson <0000176a9d5ebad7-dmarc-requ...@jiscmail.ac.uk> Sent: Monday, August 20, 2018 7:55 PM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] Protein is dimmer in solution, hard to build two chains in crystal structure 75% solvent is not uncommon, and such crystals often only diffract to 3A. Eleanor On 20 August 2018 at 10:24, SUBSCRIBE CCP4BB Zhu Qiao <jasonqia...@gmail.com<mailto:jasonqia...@gmail.com>> 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 ________________________________ To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1 ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
