Abstract
The structure of human carbonic anhydrase II at pH 9.5 has been studied by X-ray crystallographic methods to 2.2 Å resolution. These studies complement those performed under acidic conditions in which the catalytically-important proton-shuttle group, His-64, exhibits conformational mobility about side-chain torsion angle χ1. However, no structural changes are observed in the conformation of His-64 at high pH. Therefore, we conclude that the protonation of His-64 (as well as zinc-bound hydroxide) may be a factor which contributes to the predominantly "out" conformation for His-64 observed at low pH.
Original language | English (US) |
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Pages (from-to) | 579-584 |
Number of pages | 6 |
Journal | Biochemical and Biophysical Research Communications |
Volume | 181 |
Issue number | 2 |
DOIs | |
State | Published - Dec 16 1991 |
Externally published | Yes |
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Molecular Biology
- Cell Biology