Hi All,
I have engineered intra-molecular disulfide bond in my protein
monomer. The protein functions as a homodimer.
In crystal structure, there is clean electron density for the S-S
bond in one monomer (bond length 2.2A), but there seems to be
slightly messy density for the same in the other monomer with (S-S
bond length of 2.7A). An alternate conformation of one of the cys
seems plausible on the messy side. There is considerable negative
density associated with this region in both monomers, more so on the
messy side.
My question is : do i need to select additional parameters or define
any sort of constraints during refinement, in order to refine this
introduced covalent bond?
Thanks much for your help.
Best
Seema Mittal
Graduate Research Assistant
Department of Biochemistry & Molecular Pharmacology,
970L Lazare Research Building,
University of Massachusetts Medical School,
364 Plantation Street,
Worcester, MA 01605
