Hello,
only a test of the biological function of mutants will tell whether
your interface is an artefact or not.
It is very well possible that an alanine mutations increases binding;
you have to inspect the interface carefully whether there were for
example buried hydrogen donors or flexible residues in the WT
interface which made the interaction less than optimal.
Regards
Wim
Dharma <[log in to unmask]> a écrit :
> Hello CCP4 users,
> Based on the crystal structure of a two molecule protein complex, I
> have mutated (alanine substitutions) one of the putative binding
> interface. The mutant binds with much higher affinity than the wild
> type.
> However, the signature plot of ITC data reveals a decrease in the
> enthalpy but increase on the entropy (deltaS). Thus overall increase
> in deltaG.
> I want to know if it’s relevant biological interface or a crystal artifact.
> Suggestions please.
>
> Thanks
> Regards
> Dharma
> Sent from my iPhone
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