Dear all,

I have a data, and it has R/Rfree problem.

The data could be processed as P212121 and P1.

The resolution was 2.9, and unit cell parameters were a=73.527, b=90.035, c=237.980, ¥á=¥â=¥ì=90 and a=73.709, b=90.099, c=238.172, ¥á=89.939, ¥â=89.945, ¥ì=89.993 for P212121 and P1, respectively.

R/Rfree was 22.3/29.4 for P1 after several refinements.

However, I couldn¡¯t decrease R/Rfree below 30.0/37.6 for P212121.

There were almost no differences on monomer structure and crystal packing between P212121 and P1 after MR, and the electron densities followed trace of peptide chain well.

Can anybody suggest me about this problem?

Thank you.

Ki Joon Cho