Coenzyme binding domain liver alcohol dehydrogenase

A crystal structure of a ternary complex of horse liver alcohol dehydrogenase with NADH and the inhibitor, dimethyl sulfoxide, first at 4.5 A resolution1365 and a further refinement to 2.9 A resolution,1366 has been published by Eklund et al. The gross structure of the ternary complex is similar to that of the free enzyme structure. Each subunit is divided into a coenzyme-binding domain and a catalytic domain. The subunits are joined together near the... 

Liver alcohol dehydrogenase subunit viewed as a CPK model. The left-hand side of the molecule is the coenzyme binding domain and the right-hand side is the catalytic domain. The catalytic zinc ion is accessible from two channels located above (not visible) and below the coenzyme binding domain. The upper channel permits approach of the nicotinamide ring of the coenzyme. The lower channel permits approach of the substrate. The substrate channel closes up, trapping the substrate inside the molecule, when both coenzyme and substrate are present. 

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