The Three Side Chain Active Site of Alcohol
Dehydrogenase

Picture created using PyMol and
PDB file 1HTB
The active site of alcohol dehydrogenase is composed of the
side chains
of the amino acids histidine and cysteine. Specifically, they are
the residues Histidine-67, Cysteine-46, and Cysteine-174. It also
contains two zinc ions that hold the hydroxyl group of the alcohol in
place, as well as an NAD cofactor which actually causes the
reaction. Since the enzyme consists of two polypeptides, alcohol
dehydrogenase is a dimer and has two active sites.

Picture made using PyMol and PDB file 1HTB
Active site of alcohol dehydrogenase (yellow) showing the two zinc ions
(red) and the NAD cofactor (orange).

Picture made using PyMol and PDB file 1HTB
Broader image of alcohol dehydrogenase showing the enzyme in its
entirety, as well as both active sites on each respective monomer.
Home