[摘要]：The neutron structure of wild-type human carbonic anhydrase II at pH 7.8 has been determined to 2.0 angstrom resolution. Detailed analysis and comparison to the previously determined structure at pH 10.0 show important differences in the protonation of key catalytic residues in the active site as well as a rearrangement of the H-bonded water network For the first time, a completed H-bonded network stretching from the Zn-bound solvent to the proton shuttling residue, His64, has been directly observed.
