Hi Joe,
I think you are wasting your time pursueing molrep.
Go for some experimental phases. Try a bromide soak or xenon
derivatisation. Provided your molrep solution is correct,
you don't need a lot of extra phase information.
Cheers, Manfred.
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On Fri, 6 Jul 2007, Joe Smith wrote:
> Hi all,
>
> We have been trying to solve a structure of protein-protein complexes using
> 3.1A data (one of the proteins is of 120kDa whereas the other is of 20kDa).
> The structure of smaller protein is known (individually-100% sequence
> identity) whereas the bigger protein does not share more than 10% sequence
> identity with the similar proteins solved from other sources.
>
> Due to some problem in getting Seleno-labelled protein, we have also been
> trying to use molecular replacement (MR) to solve the structure. We want to
> find out the correct position of smaller protein using MR and then plan to
> extend the phases to the whole asymmetric unit (we hope it could be done but
> not sure). We are more or less sure about the fold of bigger protein and
> expect it to be similar to the other known related structures.
> In one of the solution obtained using phaser, the map looks really good, but
> this solution doesn't provide good packing of the complex inside the unit
> cell. Due to low scattering contribution of the smaller protein, we are
> unable to refine any possible solutions using REFMAC.
>
> We welcome any kind of suggestions in this regard.
>
> Thanking you in advance.
>
> Joe
>
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