The three-dimensional structure of retinol-binding protein.

Abstract
The complex of retinol with its carrier protein, retinol‐binding protein (RBP) has been crystallized and its three‐dimensional structure determined using X‐ray crystallography. Its most striking feature is an eight‐stranded up‐and‐down beta barrel core that completely encapsulates the retinol molecule. The retinol molecule lies along the axis of the barrel with the beta‐ionone ring innermost and the tip of the isoprene tail close to the surface.