It would be useful to know how you tried to solve the structure by MR. Just because there is a large number of chains in the ASU isn't a reason that MR will fail. At times you need to find some of the chains, do some rebuilding, and then use that amended model for a continued search.
Bernie Santarsiero Univ of Illinois at Chicago On Thu, March 15, 2007 12:00 pm, Yi Xue wrote: > Dear all: > We already got nice crystals of a drug-protein complex, however, MR > failed due to the huge copies (>12) of protein molecules per asu. Protein > itself is a small one, only ~70 aa. > Later on, we collected MAD data of copper (copper : protein ~ 1: 1), > Rsym of the data was around ~9%, the anomalous signals were weak, and > only > good to ~6A, the data also failed to solve the phases. > Thus, basically, the Cu anomallous signal is very weak, and the > crystals are kind of sensitive to radiation, it is dying but not that > fast. > I am wondering, Do we stand any chances to solve the phases by Cu > MAD > or SAD? > > > Any suggestions or comments are highly appreciated? > Yi >
