In article <01GO32J3NJNY9357M2 at minna.iit.edu> , CMSMUELLER at KARL.IIT.EDU
writes:
>Does anyone know the relationship between the number of
>histidine residues and the binding affinity to Zn++?
Therw was an article in "Protein Engineering" somewhen in 1991 which look
at binding of metal ions to his and asp/glu residues in proteins.
Also, the residues which bind a Zn ion seem to be dependent on the nature
of the substrate of the protein. e.g., astacin, stromelysin, collagenase,
thermolysin, etc, etc, which have a neutral substrate, bind the Zn with
two his and one asp/glu residue, whereas e.g. carbonic anhydrase has 3
his residues. That's about the limit of my knowledge. Hope it helps.
James Petts
********************************************************************
* "We use the classical theory on Mondays, Wednesdays and Fridays, *
* and the quantum theory on Tuesdays, Thursdays and Saturdays." *
************************************** Wm. Bragg *******************
