Figure 4 - full size


Figure 4.
Figure 4 Proposed mechanism for -CA. (A) Bicarbonate bound in the active site, in a position similar to that seen for the acetic acid molecule, forming hydrogen bonds with Gly224, Asp162 and Glu151. (B) This molecule decomposes into CO[2], which continues to interact with Gln151' and hydroxide. (C) CO[2] diffuses out of the active site leaving a hydroxide ion bound to the zinc. This ion then accepts a proton from a buffer molecule in bulk solvent, leaving water bound at the active site zinc (D).

The above figure is reprinted from an Open Access publication published by Macmillan Publishers Ltd: EMBO J (2000, 19, 1407-1418) copyright 2000.