Hello all,
I have recently solved a 2.0 angstrom resolution structure. The structure
is near complete but I have some unusual density at the crystallographic
interface between two chains of different asymmetric units. The linked
photos show the density at with a Fo-Fc at 3 sigma and 2Fo-Fc at 1
It's possibly a transition metal ion. Zinc is a common adventitious
contaminant of solutions. Typical Zn-O distances (tetrahedral or
pseudo-tetrahedral coordination) are 2.0 A. ICP-OES or ICP-MS of the
protein solution might offer a clue to the possible identity of the
metal ion, since it
On Mon, Feb 4, 2013 at 12:24 PM, Roger Rowlett rrowl...@colgate.edu wrote:
It's possibly a transition metal ion. Zinc is a common adventitious
contaminant of solutions. Typical Zn-O distances (tetrahedral or
pseudo-tetrahedral coordination) are 2.0 A. ICP-OES or ICP-MS of the protein
solution