Ionizable groups

Peter Swaren peter at
Wed Jul 5 08:50:00 EST 1995

--Dear Everybody again,

Thanks for the answers. What I decided to do was to restore the charge
distributions of termini to that of common backbone according to what Jack
Tanner wrote. But for His I generated the structure and coordinate files as 
if they were doubly protonated and I then turned off the charges of the His
side chain in addition to Arg, Lys, Asp, and Glu side-chain charges. At a
later stage when I have included water molecules in my model, I intend to
use these to determine which of the His nitrogen atoms should be protonated.
Then I will turn on all charges (including the side chains of Arg, Lys, Asp,
and Glu as well as His and termini) during the last refinement cycles.
Comments about this?


Groupe de cristallographie biologique du LPTF 

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