The Physicochemical Properties of RBP

Human RBP has a molecular weight of 21,200 (Peterson, 1971a) to 21,300 (Raz et al., 1970), as determined by sedimentation equilibrium analysis in the analytical ultracentrifuge. The molecular weight calculated from the reported 

Solutions of the retinol-RBP complex are highly fluorescent. The fluorescence properties of human RBP have been studied in detail (Peterson and Rask, 1971 Goodman and Leslie, 1972), and information is also available about the fluorescence spectral properties of RBP isolated from several other species. Retinol bound to RBP has uncorrected peak excitation and emission maxima of 334 and 463 nm, respectively. The relative fluorescence intensity of retinol bound to RBP (in aqueous solution) is an order of magnitude greater than that of retinol in solution in any one of a variety of organic solvents (Goodman and Leslie, 1972 Futterman et al., 1975). In addition, for retinol bound to RBP, the 

Studies employing circular dichroism and optical rotary dispersion have shown that RBP appears to have a relatively high content of unordered conformation, a significant but small complement of P conformation, and little or no a-helix (Rask et al., 1972 Gotto et al., 1972). The crystallization of RBP as long needles has been reported (Haupt and Heide, 1972). 

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