The structure of the 9-ethyl analogue of vitamin A acid

Crystallographic refinement of human serum retinol binding protein at 2A resolution

Human serum retinol binding protein (RBP) in complex with retinol has been crystallographically refined to an R-factor of 18.1% with 2A resolution data. The protein topology results in an anti-parallel beta-barrel that encapsulates the retinol ligand. A detailed description of the protein and the binding site is provided. Our structural work has helped to define a family of proteins, many of which are carrier proteins for smaller ligand molecules. We describe the structural basis for the conservation of sequence within the family.

Analysis of N-(4-hydroxyphenyl)retinamide polymorphic forms by X-ray powder diffraction

A quantitative X-ray diffraction method, with zinc oxide used as the internal standard, was developed for the analysis of polymorphic forms I and II of N-(4-hydroxyphenyl)retinamide. The standard curve relating peak height ratio to the percentage of form I was linear. The method was precise and accurate to within +/- 6%.