Hi Jacob On 9 May 2017 at 14:03, Keller, Jacob <kell...@janelia.hhmi.org> wrote:
> Wouldn’t the not-bonded CO2 have a new steric clash with the CG, though? > I think the CG can easily swing out of the way, since it's now only attached to the CB. > And what happened to the radical that was presumably generated? > Good question: if the GLU was (-) charged as seems likely then the bond-breaking X-ray photon would generate a fleeting -CH2(-) carbanion at the CG, not a radical. This would need to rapidly pick up an H+ from somewhere - but there must be plenty of those around! > Also, I would think solvent-exposed side chains would be more prone to > diffusion than buried ones. > Agree but what matters is the absolute rate of diffusion, not the rate in protein v. vitrified solvent. If the CO2 is happy where it is why should it diffuse away? After all presumably the carboxylate was happy in that position. I admit this is all pure speculation, but our map is remarkably similar to Ed's. Cheers -- Ian
