During the crystallization of a totally unrelated protein from a different bacterium in E. coli, we managed to somehow crystallize an E. coli protein. It turned out to be only the catalytic domain of an enzyme. Two previous reports both used recombinant expression of this enzyme followed by limited proteolysis in order to crystallize this domain.

Has something like this been reported before? I know the stories of AcrB etc., but I am looking specifically for a 'naturally proteolyzed' crystallization.

Looking at our structure and the previously published one, there is not much difference, with an rmsd of about 0.3 A but our data resolution is a bit higher. This is perhaps unsurprising as the unit cells are very similar (in fact, I just did a quick RBR). Should we bother depositing and publishing this observation?

Thanks.
Mohamed