Multimer search with single pdb and tNCS
Hi Massimo,
Just replying to a user who seems to be confused about how to run Phaser in the case of tNCS, and I wanted to double-check one thing about the plans for Voyager. If you have a symmetric search model that has a rotational axis that lines up with a crystallographic rotational symmetry axis, this will generate tNCS but the tNCS can’t be applied to the whole symmetric search model. To give a concrete example, if you have a dimer and its 2-fold lines up with a crystallographic 2-fold, the symmetry related dimer will look like the original one in the same orientation but chain B of the symmetry copy will be related by the tNCS translation to chain A of the original copy and vice versa. Potentially we could be taking the internal symmetry into account, but I don’t think there’s any code to do that in phaser or phasertng.
Anyway, I wanted to check that Voyager won’t run into this problem of using a multimer as a search model and then having the tNCS copies rejected because of clashes!
Randy