Hi everyone,

I have got a 4.2A SeMet MAD dataset for a protein-DNA complex.  And, the native dataset for this protein-DNA complex is ~3.2A. The space group for the native and SeMet crystals seem to be different.  I am not sure whether it’s possible to solve the structure with the current data I have, and wondering whether any of you have experience with working with this low-resolution data and any suggestion for me.

I processed the data with XDS in space group P31, and used *.cns.hkl file from XDSCONV as an input for AutoSol and also include the sequence for protein only.  The protein dimer has 418 residues and DNA is 32bp. I run Autosol with the default setting. Below is statistics I got. It seems that I didn’t get anything promising. Any comment or suggestion about what to try next? Thank you so much!

Statistics: 

Top solution: 2           Sites: 11.                     Space group: P32.            FOM: 0.550.       

BAYES-CC: 8.10.          Residues: 465           Side-chains: 0.                  Chains: 60.

Model CC:  0.67           R-work: 0.4100          R-free: 0.4569.

Under Heavy-atom search and phasing:

Best,
Wei